When using the frame pointer unwinder, it was found that the stack trace
output of stack_trace_save() is incomplete if the stack contains
call_with_stack():
[0x7f00002c] dump_stack_task+0x2c/0x90 [hrtimer]
[0x7f0000a0] hrtimer_hander+0x10/0x18 [hrtimer]
[0x801a67f0] __hrtimer_run_queues+0x1b0/0x3b4
[0x801a7350] hrtimer_run_queues+0xc4/0xd8
[0x801a597c] update_process_times+0x3c/0x88
[0x801b5a98] tick_periodic+0x50/0xd8
[0x801b5bf4] tick_handle_periodic+0x24/0x84
[0x8010ffc4] twd_handler+0x38/0x48
[0x8017d220] handle_percpu_devid_irq+0xa8/0x244
[0x80176e9c] generic_handle_domain_irq+0x2c/0x3c
[0x8052e3a8] gic_handle_irq+0x7c/0x90
[0x808ab15c] generic_handle_arch_irq+0x60/0x80
[0x8051191c] call_with_stack+0x1c/0x20
For the frame pointer unwinder, unwind_frame() checks stackframe::fp by
stackframe::sp. Since call_with_stack() switches the SP from one stack
to another, stackframe::fp and stackframe: :sp will point to different
stacks, so we can no longer check stackframe::fp by stackframe::sp. Skip
checking stackframe::fp at this point to avoid this problem.
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Reviewed-by: Linus Waleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
The objects placed at the head of vmlinux need special treatments:
- arch/$(SRCARCH)/Makefile adds them to head-y in order to place
them before other archives in the linker command line.
- arch/$(SRCARCH)/kernel/Makefile adds them to extra-y instead of
obj-y to avoid them going into built-in.a.
This commit gets rid of the latter.
Create vmlinux.a to collect all the objects that are unconditionally
linked to vmlinux. The objects listed in head-y are moved to the head
of vmlinux.a by using 'ar m'.
With this, arch/$(SRCARCH)/kernel/Makefile can consistently use obj-y
for builtin objects.
There is no *.o that is directly linked to vmlinux. Drop unneeded code
in scripts/clang-tools/gen_compile_commands.py.
$(AR) mPi needs 'T' to workaround the llvm-ar bug. The fix was suggested
by Nathan Chancellor [1].
[1]: https://lore.kernel.org/llvm/YyjjT5gQ2hGMH0ni@dev-arch.thelio-3990X/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Move some code that is only reachable when IS_ENABLED(CONFIG_ARM) into
the ARM EFI arch code.
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Function show_regs() is usually called in interrupt handler or exception
handler, it prints the registers specified by the parameter 'regs', then
dump the stack traces. Although not explicitly documented, dump the stack
traces based on'regs' seems to make the most sense. Although dump_stack()
can finally dump the desired content, because 'regs' are saved by the
entry of current interrupt or exception. In the following example we can
see: 1) The backtrace of interrupt or exception handler is not expected,
it causes confusion. 2) Something is printed repeatedly. The line with
the kernel version "CPU: 0 PID: 70 Comm: test0 Not tainted 5.19.0+ #8",
the registers saved in "Exception stack" which 'regs' actually point to.
For example:
rcu: INFO: rcu_sched self-detected stall on CPU
rcu: 0-....: (499 ticks this GP) idle=379/1/0x40000002 softirq=91/91 fqs=249
(t=500 jiffies g=-911 q=13 ncpus=4)
CPU: 0 PID: 70 Comm: test0 Not tainted 5.19.0+ #8
Hardware name: ARM-Versatile Express
PC is at ktime_get+0x4c/0xe8
LR is at ktime_get+0x4c/0xe8
pc : 8019a474 lr : 8019a474 psr: 60000013
sp : cabd1f28 ip : 00000001 fp : 00000005
r10: 527bf1b8 r9 : 431bde82 r8 : d7b634db
r7 : 0000156e r6 : 61f234f8 r5 : 00000001 r4 : 80ca86c0
r3 : ffffffff r2 : fe5bce0b r1 : 00000000 r0 : 01a431f4
Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Control: 10c5387d Table: 6121406a DAC: 00000051
CPU: 0 PID: 70 Comm: test0 Not tainted 5.19.0+ #8 <-----------start----------
Hardware name: ARM-Versatile Express |
unwind_backtrace from show_stack+0x10/0x14 |
show_stack from dump_stack_lvl+0x40/0x4c |
dump_stack_lvl from rcu_dump_cpu_stacks+0x10c/0x134 |
rcu_dump_cpu_stacks from rcu_sched_clock_irq+0x780/0xaf4 |
rcu_sched_clock_irq from update_process_times+0x54/0x74 |
update_process_times from tick_periodic+0x3c/0xd4 |
tick_periodic from tick_handle_periodic+0x20/0x80 worthless
tick_handle_periodic from twd_handler+0x30/0x40 or
twd_handler from handle_percpu_devid_irq+0x8c/0x1c8 duplicated
handle_percpu_devid_irq from generic_handle_domain_irq+0x24/0x34 |
generic_handle_domain_irq from gic_handle_irq+0x74/0x88 |
gic_handle_irq from generic_handle_arch_irq+0x34/0x44 |
generic_handle_arch_irq from call_with_stack+0x18/0x20 |
call_with_stack from __irq_svc+0x98/0xb0 |
Exception stack(0xcabd1ed8 to 0xcabd1f20) |
1ec0: 01a431f4 00000000 |
1ee0: fe5bce0b ffffffff 80ca86c0 00000001 61f234f8 0000156e d7b634db 431bde82 |
1f00: 527bf1b8 00000005 00000001 cabd1f28 8019a474 8019a474 60000013 ffffffff |
__irq_svc from ktime_get+0x4c/0xe8 <---------end--------------
ktime_get from test_task+0x44/0x110
test_task from kthread+0xd8/0xf4
kthread from ret_from_fork+0x14/0x2c
Exception stack(0xcabd1fb0 to 0xcabd1ff8)
1fa0: 00000000 00000000 00000000 00000000
1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
1fe0: 00000000 00000000 00000000 00000000 00000013 00000000
After replacing dump_stack() with dump_backtrace():
rcu: INFO: rcu_sched self-detected stall on CPU
rcu: 0-....: (500 ticks this GP) idle=8f7/1/0x40000002 softirq=129/129 fqs=241
(t=500 jiffies g=-915 q=13 ncpus=4)
CPU: 0 PID: 69 Comm: test0 Not tainted 5.19.0+ #9
Hardware name: ARM-Versatile Express
PC is at ktime_get+0x4c/0xe8
LR is at ktime_get+0x4c/0xe8
pc : 8019a494 lr : 8019a494 psr: 60000013
sp : cabddf28 ip : 00000001 fp : 00000002
r10: 0779cb48 r9 : 431bde82 r8 : d7b634db
r7 : 00000a66 r6 : e835ab70 r5 : 00000001 r4 : 80ca86c0
r3 : ffffffff r2 : ff337d39 r1 : 00000000 r0 : 00cc82c6
Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Control: 10c5387d Table: 611d006a DAC: 00000051
ktime_get from test_task+0x44/0x110
test_task from kthread+0xd8/0xf4
kthread from ret_from_fork+0x14/0x2c
Exception stack(0xcabddfb0 to 0xcabddff8)
dfa0: 00000000 00000000 00000000 00000000
dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
dfe0: 00000000 00000000 00000000 00000000 00000013 00000000
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Now that everything except StrongARM is unified under
CONFIG_ARCH_MULTIPLATFORM, the option is rather meaningless
in its current form.
Rework the Kconfig logic to make this useful again, similar
to the way that RISC-V has CONFIG_NONPORTABLE (with the
opposite polarity), this now controls the visibility of
options that get in the way of building generic kernels,
while allowing custom kernels.
One side-effect is that 'randconfig' builds now rarely hit
strongarm machines, rather than testing them three quarters
of the time.
* 'arm-multiplatform-cleanup' of https://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
ARM: make ARCH_MULTIPLATFORM user-visible
ARM: fix XIP_KERNEL dependencies
ARM: Kconfig: clean up platform selection
ARM: simplify machdirs/platdirs handling
ARM: remove obsolete Makefile.boot infrastructure
The dma-isa.c was shared between footbridge and shark a long time ago,
but as shark was removed, it can be made footbridge specific again.
The fb_dma bits in turn are not used at all and can be removed.
All the ISA related files are now built into the platform regardless
of CONFIG_ISA, as they just refer to on-chip devices rather than actual
ISA cards.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Remove the CONFIG_PREEMPT_RT symbol from the ifdef around
do_softirq_own_stack() and move it to Kconfig instead.
Enable softirq stacks based on SOFTIRQ_ON_OWN_STACK which depends on
HAVE_SOFTIRQ_ON_OWN_STACK and its default value is set to !PREEMPT_RT.
This ensures that softirq stacks are not used on PREEMPT_RT and avoids
a 'select' statement on an option which has a 'depends' statement.
Link: https://lore.kernel.org/YvN5E%2FPrHfUhggr7@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The hardware automatically disable the IRQ interrupt before jumping to the
interrupt or exception vector. Therefore, the preempt_disable() operation
in this_cpu_read() after macro expansion is unnecessary. In fact, function
this_cpu_read() may trigger scheduling, see pseudocode below.
Pseudocode of this_cpu_read(xx):
preempt_disable_notrace();
raw_cpu_read(xx);
if (unlikely(__preempt_count_dec_and_test()))
__preempt_schedule_notrace();
Therefore, use raw_cpu_* instead of this_cpu_* to eliminate potential
hazards. At the very least, it reduces a few lines of assembly code.
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
When user undefined instruction debug is enabled pc value is hashed like
kernel pointers for security reason. But the security benefit of this
hash is very limited because the code goes on to call __show_regs() that
prints the plain pointer value. pc is a user pointer anyway, so the
kernel does not leak anything. The only result is confusion about the
difference between the pc value on the first printed line, and the value
that __show_regs() prints.
Always print the plain value of pc.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Some options like CONFIG_DEBUG_UNCOMPRESS and CONFIG_CMDLINE_FORCE are
fundamentally incompatible with portable kernels but are currently allowed
in all configurations. Other options like XIP_KERNEL are essentially
useless after the completion of the multiplatform conversion.
Repurpose the existing CONFIG_ARCH_MULTIPLATFORM option to decide
whether the resulting kernel image is meant to be portable or not,
and using this to guard all of the known incompatible options.
This is similar to how the RISC-V kernel handles the CONFIG_NONPORTABLE
option (with the opposite polarity).
A few references to CONFIG_ARCH_MULTIPLATFORM were left behind by
earlier clanups and have to be removed now up.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
fatfs, autofs, squashfs, procfs, etc.
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Merge tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc updates from Andrew Morton:
"Updates to various subsystems which I help look after. lib, ocfs2,
fatfs, autofs, squashfs, procfs, etc. A relatively small amount of
material this time"
* tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits)
scripts/gdb: ensure the absolute path is generated on initial source
MAINTAINERS: kunit: add David Gow as a maintainer of KUnit
mailmap: add linux.dev alias for Brendan Higgins
mailmap: update Kirill's email
profile: setup_profiling_timer() is moslty not implemented
ocfs2: fix a typo in a comment
ocfs2: use the bitmap API to simplify code
ocfs2: remove some useless functions
lib/mpi: fix typo 'the the' in comment
proc: add some (hopefully) insightful comments
bdi: remove enum wb_congested_state
kernel/hung_task: fix address space of proc_dohung_task_timeout_secs
lib/lzo/lzo1x_compress.c: replace ternary operator with min() and min_t()
squashfs: support reading fragments in readahead call
squashfs: implement readahead
squashfs: always build "file direct" version of page actor
Revert "squashfs: provide backing_dev_info in order to disable read-ahead"
fs/ocfs2: Fix spelling typo in comment
ia64: old_rr4 added under CONFIG_HUGETLB_PAGE
proc: fix test for "vsyscall=xonly" boot option
...
Lin, Yang Shi, Anshuman Khandual and Mike Rapoport
- Some kmemleak fixes from Patrick Wang and Waiman Long
- DAMON updates from SeongJae Park
- memcg debug/visibility work from Roman Gushchin
- vmalloc speedup from Uladzislau Rezki
- more folio conversion work from Matthew Wilcox
- enhancements for coherent device memory mapping from Alex Sierra
- addition of shared pages tracking and CoW support for fsdax, from
Shiyang Ruan
- hugetlb optimizations from Mike Kravetz
- Mel Gorman has contributed some pagealloc changes to improve latency
and realtime behaviour.
- mprotect soft-dirty checking has been improved by Peter Xu
- Many other singleton patches all over the place
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Merge tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"Most of the MM queue. A few things are still pending.
Liam's maple tree rework didn't make it. This has resulted in a few
other minor patch series being held over for next time.
Multi-gen LRU still isn't merged as we were waiting for mapletree to
stabilize. The current plan is to merge MGLRU into -mm soon and to
later reintroduce mapletree, with a view to hopefully getting both
into 6.1-rc1.
Summary:
- The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe
Lin, Yang Shi, Anshuman Khandual and Mike Rapoport
- Some kmemleak fixes from Patrick Wang and Waiman Long
- DAMON updates from SeongJae Park
- memcg debug/visibility work from Roman Gushchin
- vmalloc speedup from Uladzislau Rezki
- more folio conversion work from Matthew Wilcox
- enhancements for coherent device memory mapping from Alex Sierra
- addition of shared pages tracking and CoW support for fsdax, from
Shiyang Ruan
- hugetlb optimizations from Mike Kravetz
- Mel Gorman has contributed some pagealloc changes to improve
latency and realtime behaviour.
- mprotect soft-dirty checking has been improved by Peter Xu
- Many other singleton patches all over the place"
[ XFS merge from hell as per Darrick Wong in
https://lore.kernel.org/all/YshKnxb4VwXycPO8@magnolia/ ]
* tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (282 commits)
tools/testing/selftests/vm/hmm-tests.c: fix build
mm: Kconfig: fix typo
mm: memory-failure: convert to pr_fmt()
mm: use is_zone_movable_page() helper
hugetlbfs: fix inaccurate comment in hugetlbfs_statfs()
hugetlbfs: cleanup some comments in inode.c
hugetlbfs: remove unneeded header file
hugetlbfs: remove unneeded hugetlbfs_ops forward declaration
hugetlbfs: use helper macro SZ_1{K,M}
mm: cleanup is_highmem()
mm/hmm: add a test for cross device private faults
selftests: add soft-dirty into run_vmtests.sh
selftests: soft-dirty: add test for mprotect
mm/mprotect: fix soft-dirty check in can_change_pte_writable()
mm: memcontrol: fix potential oom_lock recursion deadlock
mm/gup.c: fix formatting in check_and_migrate_movable_page()
xfs: fail dax mount if reflink is enabled on a partition
mm/memcontrol.c: remove the redundant updating of stats_flush_threshold
userfaultfd: don't fail on unrecognized features
hugetlb_cgroup: fix wrong hugetlb cgroup numa stat
...
There are three independent sets of changes:
- Sai Prakash Ranjan adds tracing support to the asm-generic
version of the MMIO accessors, which is intended to help
understand problems with device drivers and has been part
of Qualcomm's vendor kernels for many years.
- A patch from Sebastian Siewior to rework the handling of
IRQ stacks in softirqs across architectures, which is
needed for enabling PREEMPT_RT.
- The last patch to remove the CONFIG_VIRT_TO_BUS option and
some of the code behind that, after the last users of this
old interface made it in through the netdev, scsi, media and
staging trees.
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Merge tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic updates from Arnd Bergmann:
"There are three independent sets of changes:
- Sai Prakash Ranjan adds tracing support to the asm-generic version
of the MMIO accessors, which is intended to help understand
problems with device drivers and has been part of Qualcomm's vendor
kernels for many years
- A patch from Sebastian Siewior to rework the handling of IRQ stacks
in softirqs across architectures, which is needed for enabling
PREEMPT_RT
- The last patch to remove the CONFIG_VIRT_TO_BUS option and some of
the code behind that, after the last users of this old interface
made it in through the netdev, scsi, media and staging trees"
* tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
uapi: asm-generic: fcntl: Fix typo 'the the' in comment
arch/*/: remove CONFIG_VIRT_TO_BUS
soc: qcom: geni: Disable MMIO tracing for GENI SE
serial: qcom_geni_serial: Disable MMIO tracing for geni serial
asm-generic/io: Add logging support for MMIO accessors
KVM: arm64: Add a flag to disable MMIO trace for nVHE KVM
lib: Add register read/write tracing support
drm/meson: Fix overflow implicit truncation warnings
irqchip/tegra: Fix overflow implicit truncation warnings
coresight: etm4x: Use asm-generic IO memory barriers
arm64: io: Use asm-generic high level MMIO accessors
arch/*: Disable softirq stacks on PREEMPT_RT.
Not much this time around, the 5.20-rc1 development updates for arm are:
- add KASAN support for vmalloc space on arm
- some sparse fixes from Ben Dooks
- rework amba device handling (so device addition isn't deferred)
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Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:
"Not much this time around, the 5.20-rc1 development updates for arm
are:
- add KASAN support for vmalloc space on arm
- some sparse fixes from Ben Dooks
- rework amba device handling (so device addition isn't deferred)"
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 9220/1: amba: Remove deferred device addition
ARM: 9219/1: fix undeclared soft_restart
ARM: 9218/1: dma-mapping: fix pointer/integer warning
ARM: 9217/1: add definition of arch_irq_work_raise()
ARM: 9203/1: kconfig: fix MODULE_PLTS for KASAN with KASAN_VMALLOC
ARM: 9202/1: kasan: support CONFIG_KASAN_VMALLOC
This pull request contains the following branches:
doc.2022.06.21a: Documentation updates.
fixes.2022.07.19a: Miscellaneous fixes.
nocb.2022.07.19a: Callback-offload updates, perhaps most notably a new
RCU_NOCB_CPU_DEFAULT_ALL Kconfig option that causes all CPUs to
be offloaded at boot time, regardless of kernel boot parameters.
This is useful to battery-powered systems such as ChromeOS
and Android. In addition, a new RCU_NOCB_CPU_CB_BOOST kernel
boot parameter prevents offloaded callbacks from interfering
with real-time workloads and with energy-efficiency mechanisms.
poll.2022.07.21a: Polled grace-period updates, perhaps most notably
making these APIs account for both normal and expedited grace
periods.
rcu-tasks.2022.06.21a: Tasks RCU updates, perhaps most notably reducing
the CPU overhead of RCU tasks trace grace periods by more than
a factor of two on a system with 15,000 tasks. The reduction
is expected to increase with the number of tasks, so it seems
reasonable to hypothesize that a system with 150,000 tasks might
see a 20-fold reduction in CPU overhead.
torture.2022.06.21a: Torture-test updates.
ctxt.2022.07.05a: Updates that merge RCU's dyntick-idle tracking into
context tracking, thus reducing the overhead of transitioning to
kernel mode from either idle or nohz_full userspace execution
for kernels that track context independently of RCU. This is
expected to be helpful primarily for kernels built with
CONFIG_NO_HZ_FULL=y.
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Merge tag 'rcu.2022.07.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu
Pull RCU updates from Paul McKenney:
- Documentation updates
- Miscellaneous fixes
- Callback-offload updates, perhaps most notably a new
RCU_NOCB_CPU_DEFAULT_ALL Kconfig option that causes all CPUs to be
offloaded at boot time, regardless of kernel boot parameters.
This is useful to battery-powered systems such as ChromeOS and
Android. In addition, a new RCU_NOCB_CPU_CB_BOOST kernel boot
parameter prevents offloaded callbacks from interfering with
real-time workloads and with energy-efficiency mechanisms
- Polled grace-period updates, perhaps most notably making these APIs
account for both normal and expedited grace periods
- Tasks RCU updates, perhaps most notably reducing the CPU overhead of
RCU tasks trace grace periods by more than a factor of two on a
system with 15,000 tasks.
The reduction is expected to increase with the number of tasks, so it
seems reasonable to hypothesize that a system with 150,000 tasks
might see a 20-fold reduction in CPU overhead
- Torture-test updates
- Updates that merge RCU's dyntick-idle tracking into context tracking,
thus reducing the overhead of transitioning to kernel mode from
either idle or nohz_full userspace execution for kernels that track
context independently of RCU.
This is expected to be helpful primarily for kernels built with
CONFIG_NO_HZ_FULL=y
* tag 'rcu.2022.07.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (98 commits)
rcu: Add irqs-disabled indicator to expedited RCU CPU stall warnings
rcu: Diagnose extended sync_rcu_do_polled_gp() loops
rcu: Put panic_on_rcu_stall() after expedited RCU CPU stall warnings
rcutorture: Test polled expedited grace-period primitives
rcu: Add polled expedited grace-period primitives
rcutorture: Verify that polled GP API sees synchronous grace periods
rcu: Make Tiny RCU grace periods visible to polled APIs
rcu: Make polled grace-period API account for expedited grace periods
rcu: Switch polled grace-period APIs to ->gp_seq_polled
rcu/nocb: Avoid polling when my_rdp->nocb_head_rdp list is empty
rcu/nocb: Add option to opt rcuo kthreads out of RT priority
rcu: Add nocb_cb_kthread check to rcu_is_callbacks_kthread()
rcu/nocb: Add an option to offload all CPUs on boot
rcu/nocb: Fix NOCB kthreads spawn failure with rcu_nocb_rdp_deoffload() direct call
rcu/nocb: Invert rcu_state.barrier_mutex VS hotplug lock locking order
rcu/nocb: Add/del rdp to iterate from rcuog itself
rcu/tree: Add comment to describe GP-done condition in fqs loop
rcu: Initialize first_gp_fqs at declaration in rcu_gp_fqs()
rcu/kvfree: Remove useless monitor_todo flag
rcu: Cleanup RCU urgency state for offline CPU
...
- lockdep: Fix a handful of the more complex lockdep_init_map_*() primitives
that can lose the lock_type & cause false reports. No such mishap was
observed in the wild.
- jump_label improvements: simplify the cross-arch support of
initial NOP patching by making it arch-specific code (used on MIPS only),
and remove the s390 initial NOP patching that was superfluous.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'locking-core-2022-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
"This was a fairly quiet cycle for the locking subsystem:
- lockdep: Fix a handful of the more complex lockdep_init_map_*()
primitives that can lose the lock_type & cause false reports. No
such mishap was observed in the wild.
- jump_label improvements: simplify the cross-arch support of initial
NOP patching by making it arch-specific code (used on MIPS only),
and remove the s390 initial NOP patching that was superfluous"
* tag 'locking-core-2022-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/lockdep: Fix lockdep_init_map_*() confusion
jump_label: make initial NOP patching the special case
jump_label: mips: move module NOP patching into arch code
jump_label: s390: avoid pointless initial NOP patching
The setup_profiling_timer() is mostly un-implemented by many
architectures. In many places it isn't guarded by CONFIG_PROFILE which is
needed for it to be used. Make it a weak symbol in kernel/profile.c and
remove the 'return -EINVAL' implementations from the kenrel.
There are a couple of architectures which do return 0 from the
setup_profiling_timer() function but they don't seem to do anything else
with it. To keep the /proc compatibility for now, leave these for a
future update or removal.
On ARM, this fixes the following sparse warning:
arch/arm/kernel/smp.c:793:5: warning: symbol 'setup_profiling_timer' was not declared. Should it be static?
Link: https://lkml.kernel.org/r/20220721195509.418205-1-ben-linux@fluff.org
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The soft_restart() is declared in <asm/system_misc.h> so
include that to fix the following sparse warning:
arch/arm/kernel/reboot.c:78:6: warning: symbol 'soft_restart' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
PMD_ORDER denotes order of magnitude for a PMD entry, i.e PMD entry size
is 2 ^ PMD_ORDER.
Rename PMD_ORDER to PMD_ENTRY_ORDER to allow a generic definition of
PMD_ORDER as order of a PMD allocation: (PMD_SHIFT - PAGE_SHIFT).
Link: https://lkml.kernel.org/r/20220705154708.181258-16-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
LKP reports a build issue on Clang, related to a literal load of
__current issued through the ldr_va macro. This turns out to be due to
the fact that group relocations are disabled when CONFIG_COMPILE_TEST=y,
which means that the ldr_va macro resolves to a pair of LDR
instructions, the first one being a literal load issued too far from its
literal pool.
Due to the introduction of a couple of new uses of this macro in commit
508074607c ("ARM: 9195/1: entry: avoid explicit literal loads"),
the literal pools end up getting rearranged in a way that causes the
literal for __current to go out of range. Let's fix this up by putting a
.ltorg directive in a suitable place in the code.
Link: https://lore.kernel.org/all/202205290805.1vZLAr36-lkp@intel.com/
Fixes: 508074607c ("ARM: 9195/1: entry: avoid explicit literal loads")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Context tracking is going to be used not only to track user transitions
but also idle/IRQs/NMIs. The user tracking part will then become a
separate feature. Prepare Kconfig for that.
[ frederic: Apply Max Filippov feedback. ]
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Cc: Uladzislau Rezki <uladzislau.rezki@sony.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicolas Saenz Julienne <nsaenz@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Cc: Yu Liao <liaoyu15@huawei.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Paul Gortmaker<paul.gortmaker@windriver.com>
Cc: Alex Belits <abelits@marvell.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
context_tracking_user_enter() and context_tracking_user_exit() are
ASM callable versions of user_enter() and user_exit() for architectures
that didn't manage to check the context tracking static key from ASM.
Change those function names to better reflect their purpose.
[ frederic: Apply Max Filippov feedback. ]
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Cc: Uladzislau Rezki <uladzislau.rezki@sony.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicolas Saenz Julienne <nsaenz@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Cc: Yu Liao <liaoyu15@huawei.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Paul Gortmaker<paul.gortmaker@windriver.com>
Cc: Alex Belits <abelits@marvell.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Instead of defaulting to patching NOP opcodes at init time, and leaving
it to the architectures to override this if this is not needed, switch
to a model where doing nothing is the default. This is the common case
by far, as only MIPS requires NOP patching at init time. On all other
architectures, the correct encodings are emitted by the compiler and so
no initial patching is needed.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220615154142.1574619-4-ardb@kernel.org
PREEMPT_RT preempts softirqs and the current implementation avoids
do_softirq_own_stack() and only uses __do_softirq().
Disable the unused softirqs stacks on PREEMPT_RT to save some memory and
ensure that do_softirq_own_stack() is not used bwcause it is not expected.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
ordinary user mode tasks.
In commit 40966e316f ("kthread: Ensure struct kthread is present for
all kthreads") caused init and the user mode helper threads that call
kernel_execve to have struct kthread allocated for them. This struct
kthread going away during execve in turned made a use after free of
struct kthread possible.
The commit 343f4c49f2 ("kthread: Don't allocate kthread_struct for
init and umh") is enough to fix the use after free and is simple enough
to be backportable.
The rest of the changes pass struct kernel_clone_args to clean things
up and cause the code to make sense.
In making init and the user mode helpers tasks purely user mode tasks
I ran into two complications. The function task_tick_numa was
detecting tasks without an mm by testing for the presence of
PF_KTHREAD. The initramfs code in populate_initrd_image was using
flush_delayed_fput to ensuere the closing of all it's file descriptors
was complete, and flush_delayed_fput does not work in a userspace thread.
I have looked and looked and more complications and in my code review
I have not found any, and neither has anyone else with the code sitting
in linux-next.
Link: https://lkml.kernel.org/r/87mtfu4up3.fsf@email.froward.int.ebiederm.org
Eric W. Biederman (8):
kthread: Don't allocate kthread_struct for init and umh
fork: Pass struct kernel_clone_args into copy_thread
fork: Explicity test for idle tasks in copy_thread
fork: Generalize PF_IO_WORKER handling
init: Deal with the init process being a user mode process
fork: Explicitly set PF_KTHREAD
fork: Stop allowing kthreads to call execve
sched: Update task_tick_numa to ignore tasks without an mm
arch/alpha/kernel/process.c | 13 ++++++------
arch/arc/kernel/process.c | 13 ++++++------
arch/arm/kernel/process.c | 12 ++++++-----
arch/arm64/kernel/process.c | 12 ++++++-----
arch/csky/kernel/process.c | 15 ++++++-------
arch/h8300/kernel/process.c | 10 ++++-----
arch/hexagon/kernel/process.c | 12 ++++++-----
arch/ia64/kernel/process.c | 15 +++++++------
arch/m68k/kernel/process.c | 12 ++++++-----
arch/microblaze/kernel/process.c | 12 ++++++-----
arch/mips/kernel/process.c | 13 ++++++------
arch/nios2/kernel/process.c | 12 ++++++-----
arch/openrisc/kernel/process.c | 12 ++++++-----
arch/parisc/kernel/process.c | 18 +++++++++-------
arch/powerpc/kernel/process.c | 15 +++++++------
arch/riscv/kernel/process.c | 12 ++++++-----
arch/s390/kernel/process.c | 12 ++++++-----
arch/sh/kernel/process_32.c | 12 ++++++-----
arch/sparc/kernel/process_32.c | 12 ++++++-----
arch/sparc/kernel/process_64.c | 12 ++++++-----
arch/um/kernel/process.c | 15 +++++++------
arch/x86/include/asm/fpu/sched.h | 2 +-
arch/x86/include/asm/switch_to.h | 8 +++----
arch/x86/kernel/fpu/core.c | 4 ++--
arch/x86/kernel/process.c | 18 +++++++++-------
arch/xtensa/kernel/process.c | 17 ++++++++-------
fs/exec.c | 8 ++++---
include/linux/sched/task.h | 8 +++++--
init/initramfs.c | 2 ++
init/main.c | 2 +-
kernel/fork.c | 46 +++++++++++++++++++++++++++++++++-------
kernel/sched/fair.c | 2 +-
kernel/umh.c | 6 +++---
33 files changed, 234 insertions(+), 160 deletions(-)
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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Merge tag 'kthread-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull kthread updates from Eric Biederman:
"This updates init and user mode helper tasks to be ordinary user mode
tasks.
Commit 40966e316f ("kthread: Ensure struct kthread is present for
all kthreads") caused init and the user mode helper threads that call
kernel_execve to have struct kthread allocated for them. This struct
kthread going away during execve in turned made a use after free of
struct kthread possible.
Here, commit 343f4c49f2 ("kthread: Don't allocate kthread_struct for
init and umh") is enough to fix the use after free and is simple
enough to be backportable.
The rest of the changes pass struct kernel_clone_args to clean things
up and cause the code to make sense.
In making init and the user mode helpers tasks purely user mode tasks
I ran into two complications. The function task_tick_numa was
detecting tasks without an mm by testing for the presence of
PF_KTHREAD. The initramfs code in populate_initrd_image was using
flush_delayed_fput to ensuere the closing of all it's file descriptors
was complete, and flush_delayed_fput does not work in a userspace
thread.
I have looked and looked and more complications and in my code review
I have not found any, and neither has anyone else with the code
sitting in linux-next"
* tag 'kthread-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
sched: Update task_tick_numa to ignore tasks without an mm
fork: Stop allowing kthreads to call execve
fork: Explicitly set PF_KTHREAD
init: Deal with the init process being a user mode process
fork: Generalize PF_IO_WORKER handling
fork: Explicity test for idle tasks in copy_thread
fork: Pass struct kernel_clone_args into copy_thread
kthread: Don't allocate kthread_struct for init and umh
- Add Tegra234 cpufreq support (Sumit Gupta).
- Clean up and enhance the Mediatek cpufreq driver (Wan Jiabing,
Rex-BC Chen, and Jia-Wei Chang).
- Fix up the CPPC cpufreq driver after recent changes (Zheng Bin,
Pierre Gondois).
- Minor update to dt-binding for Qcom's opp-v2-kryo-cpu (Yassine
Oudjana).
- Use list iterator only inside the list_for_each_entry loop (Xiaomeng
Tong, and Jakob Koschel).
- New APIs related to finding OPP based on interconnect bandwidth
(Krzysztof Kozlowski).
- Fix the missing of_node_put() in _bandwidth_supported() (Dan
Carpenter).
- Cleanups (Krzysztof Kozlowski, and Viresh Kumar).
- Add Out of Band mode description to the intel-speed-select utility
documentation (Srinivas Pandruvada).
- Add power sequences support to the system reboot and power off
code and make related platform-specific changes for multiple
platforms (Dmitry Osipenko, Geert Uytterhoeven).
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Merge tag 'pm-5.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management updates from Rafael Wysocki:
"These update the ARM cpufreq drivers and fix up the CPPC cpufreq
driver after recent changes, update the OPP code and PM documentation
and add power sequences support to the system reboot and power off
code.
Specifics:
- Add Tegra234 cpufreq support (Sumit Gupta)
- Clean up and enhance the Mediatek cpufreq driver (Wan Jiabing,
Rex-BC Chen, and Jia-Wei Chang)
- Fix up the CPPC cpufreq driver after recent changes (Zheng Bin,
Pierre Gondois)
- Minor update to dt-binding for Qcom's opp-v2-kryo-cpu (Yassine
Oudjana)
- Use list iterator only inside the list_for_each_entry loop
(Xiaomeng Tong, and Jakob Koschel)
- New APIs related to finding OPP based on interconnect bandwidth
(Krzysztof Kozlowski)
- Fix the missing of_node_put() in _bandwidth_supported() (Dan
Carpenter)
- Cleanups (Krzysztof Kozlowski, and Viresh Kumar)
- Add Out of Band mode description to the intel-speed-select utility
documentation (Srinivas Pandruvada)
- Add power sequences support to the system reboot and power off code
and make related platform-specific changes for multiple platforms
(Dmitry Osipenko, Geert Uytterhoeven)"
* tag 'pm-5.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (60 commits)
cpufreq: CPPC: Fix unused-function warning
cpufreq: CPPC: Fix build error without CONFIG_ACPI_CPPC_CPUFREQ_FIE
Documentation: admin-guide: PM: Add Out of Band mode
kernel/reboot: Change registration order of legacy power-off handler
m68k: virt: Switch to new sys-off handler API
kernel/reboot: Add devm_register_restart_handler()
kernel/reboot: Add devm_register_power_off_handler()
soc/tegra: pmc: Use sys-off handler API to power off Nexus 7 properly
reboot: Remove pm_power_off_prepare()
regulator: pfuze100: Use devm_register_sys_off_handler()
ACPI: power: Switch to sys-off handler API
memory: emif: Use kernel_can_power_off()
mips: Use do_kernel_power_off()
ia64: Use do_kernel_power_off()
x86: Use do_kernel_power_off()
sh: Use do_kernel_power_off()
m68k: Switch to new sys-off handler API
powerpc: Use do_kernel_power_off()
xen/x86: Use do_kernel_power_off()
parisc: Use do_kernel_power_off()
...
- The majority of the changes are for fixes and clean ups.
Noticeable changes:
- Rework trace event triggers code to be easier to interact with.
- Support for embedding bootconfig with the kernel (as suppose to having it
embedded in initram). This is useful for embedded boards without initram
disks.
- Speed up boot by parallelizing the creation of tracefs files.
- Allow absolute ring buffer timestamps handle timestamps that use more than
59 bits.
- Added new tracing clock "TAI" (International Atomic Time)
- Have weak functions show up in available_filter_function list as:
__ftrace_invalid_address___<invalid-offset>
instead of using the name of the function before it.
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Merge tag 'trace-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"The majority of the changes are for fixes and clean ups.
Notable changes:
- Rework trace event triggers code to be easier to interact with.
- Support for embedding bootconfig with the kernel (as suppose to
having it embedded in initram). This is useful for embedded boards
without initram disks.
- Speed up boot by parallelizing the creation of tracefs files.
- Allow absolute ring buffer timestamps handle timestamps that use
more than 59 bits.
- Added new tracing clock "TAI" (International Atomic Time)
- Have weak functions show up in available_filter_function list as:
__ftrace_invalid_address___<invalid-offset> instead of using the
name of the function before it"
* tag 'trace-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (52 commits)
ftrace: Add FTRACE_MCOUNT_MAX_OFFSET to avoid adding weak function
tracing: Fix comments for event_trigger_separate_filter()
x86/traceponit: Fix comment about irq vector tracepoints
x86,tracing: Remove unused headers
ftrace: Clean up hash direct_functions on register failures
tracing: Fix comments of create_filter()
tracing: Disable kcov on trace_preemptirq.c
tracing: Initialize integer variable to prevent garbage return value
ftrace: Fix typo in comment
ftrace: Remove return value of ftrace_arch_modify_*()
tracing: Cleanup code by removing init "char *name"
tracing: Change "char *" string form to "char []"
tracing/timerlat: Do not wakeup the thread if the trace stops at the IRQ
tracing/timerlat: Print stacktrace in the IRQ handler if needed
tracing/timerlat: Notify IRQ new max latency only if stop tracing is set
kprobes: Fix build errors with CONFIG_KRETPROBES=n
tracing: Fix return value of trace_pid_write()
tracing: Fix potential double free in create_var_ref()
tracing: Use strim() to remove whitespace instead of doing it manually
ftrace: Deal with error return code of the ftrace_process_locs() function
...
subsystems. Most notably some maintenance work in ocfs2 and initramfs.
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Merge tag 'mm-nonmm-stable-2022-05-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc updates from Andrew Morton:
"The non-MM patch queue for this merge window.
Not a lot of material this cycle. Many singleton patches against
various subsystems. Most notably some maintenance work in ocfs2
and initramfs"
* tag 'mm-nonmm-stable-2022-05-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (65 commits)
kcov: update pos before writing pc in trace function
ocfs2: dlmfs: fix error handling of user_dlm_destroy_lock
ocfs2: dlmfs: don't clear USER_LOCK_ATTACHED when destroying lock
fs/ntfs: remove redundant variable idx
fat: remove time truncations in vfat_create/vfat_mkdir
fat: report creation time in statx
fat: ignore ctime updates, and keep ctime identical to mtime in memory
fat: split fat_truncate_time() into separate functions
MAINTAINERS: add Muchun as a memcg reviewer
proc/sysctl: make protected_* world readable
ia64: mca: drop redundant spinlock initialization
tty: fix deadlock caused by calling printk() under tty_port->lock
relay: remove redundant assignment to pointer buf
fs/ntfs3: validate BOOT sectors_per_clusters
lib/string_helpers: fix not adding strarray to device's resource list
kernel/crash_core.c: remove redundant check of ck_cmdline
ELF, uapi: fixup ELF_ST_TYPE definition
ipc/mqueue: use get_tree_nodev() in mqueue_get_tree()
ipc: update semtimedop() to use hrtimer
ipc/sem: remove redundant assignments
...
All instances of the function ftrace_arch_modify_prepare() and
ftrace_arch_modify_post_process() return zero. There's no point in
checking their return value. Just have them be void functions.
Link: https://lkml.kernel.org/r/20220518023639.4065-1-kunyu@nfschina.com
Signed-off-by: Li kunyu <kunyu@nfschina.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Platform PMU changes:
=====================
- x86/intel:
- Add new Intel Alder Lake and Raptor Lake support
- x86/amd:
- AMD Zen4 IBS extensions support
- Add AMD PerfMonV2 support
- Add AMD Fam19h Branch Sampling support
Generic changes:
================
- signal: Deliver SIGTRAP on perf event asynchronously if blocked
Perf instrumentation can be driven via SIGTRAP, but this causes a problem
when SIGTRAP is blocked by a task & terminate the task.
Allow user-space to request these signals asynchronously (after they get
unblocked) & also give the information to the signal handler when this
happens:
" To give user space the ability to clearly distinguish synchronous from
asynchronous signals, introduce siginfo_t::si_perf_flags and
TRAP_PERF_FLAG_ASYNC (opted for flags in case more binary information is
required in future).
The resolution to the problem is then to (a) no longer force the signal
(avoiding the terminations), but (b) tell user space via si_perf_flags
if the signal was synchronous or not, so that such signals can be
handled differently (e.g. let user space decide to ignore or consider
the data imprecise). "
- Unify/standardize the /sys/devices/cpu/events/* output format.
- Misc fixes & cleanups.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'perf-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf events updates from Ingo Molnar:
"Platform PMU changes:
- x86/intel:
- Add new Intel Alder Lake and Raptor Lake support
- x86/amd:
- AMD Zen4 IBS extensions support
- Add AMD PerfMonV2 support
- Add AMD Fam19h Branch Sampling support
Generic changes:
- signal: Deliver SIGTRAP on perf event asynchronously if blocked
Perf instrumentation can be driven via SIGTRAP, but this causes a
problem when SIGTRAP is blocked by a task & terminate the task.
Allow user-space to request these signals asynchronously (after
they get unblocked) & also give the information to the signal
handler when this happens:
"To give user space the ability to clearly distinguish
synchronous from asynchronous signals, introduce
siginfo_t::si_perf_flags and TRAP_PERF_FLAG_ASYNC (opted for
flags in case more binary information is required in future).
The resolution to the problem is then to (a) no longer force the
signal (avoiding the terminations), but (b) tell user space via
si_perf_flags if the signal was synchronous or not, so that such
signals can be handled differently (e.g. let user space decide
to ignore or consider the data imprecise). "
- Unify/standardize the /sys/devices/cpu/events/* output format.
- Misc fixes & cleanups"
* tag 'perf-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
perf/x86/amd/core: Fix reloading events for SVM
perf/x86/amd: Run AMD BRS code only on supported hw
perf/x86/amd: Fix AMD BRS period adjustment
perf/x86/amd: Remove unused variable 'hwc'
perf/ibs: Fix comment
perf/amd/ibs: Advertise zen4_ibs_extensions as pmu capability attribute
perf/amd/ibs: Add support for L3 miss filtering
perf/amd/ibs: Use ->is_visible callback for dynamic attributes
perf/amd/ibs: Cascade pmu init functions' return value
perf/x86/uncore: Add new Alder Lake and Raptor Lake support
perf/x86/uncore: Clean up uncore_pci_ids[]
perf/x86/cstate: Add new Alder Lake and Raptor Lake support
perf/x86/msr: Add new Alder Lake and Raptor Lake support
perf/x86: Add new Alder Lake and Raptor Lake support
perf/amd/ibs: Use interrupt regs ip for stack unwinding
perf/x86/amd/core: Add PerfMonV2 overflow handling
perf/x86/amd/core: Add PerfMonV2 counter control
perf/x86/amd/core: Detect available counters
perf/x86/amd/core: Detect PerfMonV2 support
x86/msr: Add PerfCntrGlobal* registers
...
For EABI stack unwinding, when loading .ko module
the EXIDX sections will be added to a unwind_table list.
However not all EXIDX sections are added because EXIDX
sections are searched by hardcoded section names.
For functions in other sections such as .ref.text
or .kprobes.text, gcc generates seprated EXIDX sections
(such as .ARM.exidx.ref.text or .ARM.exidx.kprobes.text).
These extra EXIDX sections are not loaded, so when unwinding
functions in these sections, we will failed with:
unwind: Index not found xxx
To fix that, I refactor the code for searching and adding
EXIDX sections:
- Check section type to search EXIDX tables (0x70000001)
instead of strcmp() the hardcoded names. Then find the
corresponding text sections by their section names.
- Add a unwind_table list in module->arch to save their own
unwind_table instead of the fixed-lenth array.
- Save .ARM.exidx.init.text section ptr, because it should
be cleaned after module init.
Now all EXIDX sections of .ko can be added correctly.
Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Enable the workaround for the 764319 Cortex A-9 erratum.
CP14 read accesses to the DBGPRSR and DBGOSLSR registers generate an
unexpected Undefined Instruction exception when the DBGSWENABLE external
pin is set to 0, even when the CP14 accesses are performed from a
privileged mode. The work around catches the exception in a way
the kernel does not stop execution with the use of undef_hook. This
has been found to effect the HPE GXP SoC.
Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
The assembler does not permit 'LDR PC, <sym>' when the symbol lives in a
different section, which is why we have been relying on rather fragile
open-coded arithmetic to load the address of the vector_swi routine into
the program counter using a single LDR instruction in the SWI slot in
the vector table. The literal was moved to a different section to in
commit 19accfd373 ("ARM: move vector stubs") to ensure that the
vector stubs page does not need to be mapped readable for user space,
which is the case for the vector page itself, as it carries the kuser
helpers as well.
So the cross-section literal load is open-coded, and this relies on the
address of vector_swi to be at the very start of the vector stubs page,
and we won't notice if we got it wrong until booting the kernel and see
it break. Fortunately, it was guaranteed to break, so this was fragile
but not problematic.
Now that we have added two other variants of the vector table, we have 3
occurrences of the same trick, and so the size of our ISA/compiler/CPU
validation space has tripled, in a way that may cause regressions to only
be observed once booting the image in question on a CPU that exercises a
particular vector table.
So let's switch to true cross section references, and let the linker fix
them up like it fixes up all the other cross section references in the
vector page.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
In order to minimize potential confusion regarding numbered labels
appearing in a different order in the assembler output due to the use of
subsections, use a named local label to jump back into the vector
handler code from the associated loop8 mitigation sequence.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
The loop8 mitigation for Spectre-BHB only requires a CPU local DSB
rather than a systemwide one, which is much more costly. And by the same
reasoning as why it is justified to omit the ISB after BPIALL, we can
also elide the ISB and rely on the exception return for the context
synchronization.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
The BPIALL mitigation for Spectre-BHB adds a single instruction to the
handler sequence that doesn't clobber any registers. Given that these
sequences are 10 instructions long, they don't fit neatly into a
cacheline anyway, so we can simply move that single instruction to the
start of the unmitigated one, and rearrange the symbol names accordingly.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
ARMv7 has MOVW/MOVT instruction pairs to load symbol addresses into
registers without having to rely on literal loads that go via the
D-cache. For older cores, we now support a similar arrangement, based
on PC-relative group relocations.
This means we can elide most literal loads entirely from the entry path,
by switching to the ldr_va macro to emit the appropriate sequence
depending on the target architecture revision.
While at it, switch to the bl_r macro for invoking the right PABT/DABT
helpers instead of setting the LR register explicitly, which does not
play well with cores that speculate across function returns.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Kernel now supports chained power-off handlers. Use do_kernel_power_off()
that invokes chained power-off handlers. It also invokes legacy
pm_power_off() for now, which will be removed once all drivers will
be converted to the new sys-off API.
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In Thumb2, 'b . + 4' produces a branch instruction that uses a narrow
encoding, and so it does not jump to the following instruction as
expected. So use W(b) instead.
Fixes: 6c7cb60bff ("ARM: fix Thumb2 regression with Spectre BHB")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Add fn and fn_arg members into struct kernel_clone_args and test for
them in copy_thread (instead of testing for PF_KTHREAD | PF_IO_WORKER).
This allows any task that wants to be a user space task that only runs
in kernel mode to use this functionality.
The code on x86 is an exception and still retains a PF_KTHREAD test
because x86 unlikely everything else handles kthreads slightly
differently than user space tasks that start with a function.
The functions that created tasks that start with a function
have been updated to set ".fn" and ".fn_arg" instead of
".stack" and ".stack_size". These functions are fork_idle(),
create_io_thread(), kernel_thread(), and user_mode_thread().
Link: https://lkml.kernel.org/r/20220506141512.516114-4-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
With io_uring we have started supporting tasks that are for most
purposes user space tasks that exclusively run code in kernel mode.
The kernel task that exec's init and tasks that exec user mode
helpers are also user mode tasks that just run kernel code
until they call kernel execve.
Pass kernel_clone_args into copy_thread so these oddball
tasks can be supported more cleanly and easily.
v2: Fix spelling of kenrel_clone_args on h8300
Link: https://lkml.kernel.org/r/20220506141512.516114-2-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Patch series "Convert vmcore to use an iov_iter", v5.
For some reason several people have been sending bad patches to fix
compiler warnings in vmcore recently. Here's how it should be done.
Compile-tested only on x86. As noted in the first patch, s390 should take
this conversion a bit further, but I'm not inclined to do that work
myself.
This patch (of 3):
Instead of passing in a 'buf' and 'userbuf' argument, pass in an iov_iter.
s390 needs more work to pass the iov_iter down further, or refactor, but
I'd be more comfortable if someone who can test on s390 did that work.
It's more convenient to convert the whole of read_from_oldmem() to take an
iov_iter at the same time, so rename it to read_from_oldmem_iter() and add
a temporary read_from_oldmem() wrapper that creates an iov_iter.
Link: https://lkml.kernel.org/r/20220408090636.560886-1-bhe@redhat.com
Link: https://lkml.kernel.org/r/20220408090636.560886-2-bhe@redhat.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
With SIGTRAP on perf events, we have encountered termination of
processes due to user space attempting to block delivery of SIGTRAP.
Consider this case:
<set up SIGTRAP on a perf event>
...
sigset_t s;
sigemptyset(&s);
sigaddset(&s, SIGTRAP | <and others>);
sigprocmask(SIG_BLOCK, &s, ...);
...
<perf event triggers>
When the perf event triggers, while SIGTRAP is blocked, force_sig_perf()
will force the signal, but revert back to the default handler, thus
terminating the task.
This makes sense for error conditions, but not so much for explicitly
requested monitoring. However, the expectation is still that signals
generated by perf events are synchronous, which will no longer be the
case if the signal is blocked and delivered later.
To give user space the ability to clearly distinguish synchronous from
asynchronous signals, introduce siginfo_t::si_perf_flags and
TRAP_PERF_FLAG_ASYNC (opted for flags in case more binary information is
required in future).
The resolution to the problem is then to (a) no longer force the signal
(avoiding the terminations), but (b) tell user space via si_perf_flags
if the signal was synchronous or not, so that such signals can be
handled differently (e.g. let user space decide to ignore or consider
the data imprecise).
The alternative of making the kernel ignore SIGTRAP on perf events if
the signal is blocked may work for some usecases, but likely causes
issues in others that then have to revert back to interception of
sigprocmask() (which we want to avoid). [ A concrete example: when using
breakpoint perf events to track data-flow, in a region of code where
signals are blocked, data-flow can no longer be tracked accurately.
When a relevant asynchronous signal is received after unblocking the
signal, the data-flow tracking logic needs to know its state is
imprecise. ]
Fixes: 97ba62b278 ("perf: Add support for SIGTRAP on perf events")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Link: https://lore.kernel.org/r/20220404111204.935357-1-elver@google.com
The following KASAN warning is detected by QEMU.
==================================================================
BUG: KASAN: stack-out-of-bounds in unwind_frame+0x508/0x870
Read of size 4 at addr c36bba90 by task cat/163
CPU: 1 PID: 163 Comm: cat Not tainted 5.10.0-rc1 #40
Hardware name: ARM-Versatile Express
[<c0113fac>] (unwind_backtrace) from [<c010e71c>] (show_stack+0x10/0x14)
[<c010e71c>] (show_stack) from [<c0b805b4>] (dump_stack+0x98/0xb0)
[<c0b805b4>] (dump_stack) from [<c0b7d658>] (print_address_description.constprop.0+0x58/0x4bc)
[<c0b7d658>] (print_address_description.constprop.0) from [<c031435c>] (kasan_report+0x154/0x170)
[<c031435c>] (kasan_report) from [<c0113c44>] (unwind_frame+0x508/0x870)
[<c0113c44>] (unwind_frame) from [<c010e298>] (__save_stack_trace+0x110/0x134)
[<c010e298>] (__save_stack_trace) from [<c01ce0d8>] (stack_trace_save+0x8c/0xb4)
[<c01ce0d8>] (stack_trace_save) from [<c0313520>] (kasan_set_track+0x38/0x60)
[<c0313520>] (kasan_set_track) from [<c0314cb8>] (kasan_set_free_info+0x20/0x2c)
[<c0314cb8>] (kasan_set_free_info) from [<c0313474>] (__kasan_slab_free+0xec/0x120)
[<c0313474>] (__kasan_slab_free) from [<c0311e20>] (kmem_cache_free+0x7c/0x334)
[<c0311e20>] (kmem_cache_free) from [<c01c35dc>] (rcu_core+0x390/0xccc)
[<c01c35dc>] (rcu_core) from [<c01013a8>] (__do_softirq+0x180/0x518)
[<c01013a8>] (__do_softirq) from [<c0135214>] (irq_exit+0x9c/0xe0)
[<c0135214>] (irq_exit) from [<c01a40e4>] (__handle_domain_irq+0xb0/0x110)
[<c01a40e4>] (__handle_domain_irq) from [<c0691248>] (gic_handle_irq+0xa0/0xb8)
[<c0691248>] (gic_handle_irq) from [<c0100b0c>] (__irq_svc+0x6c/0x94)
Exception stack(0xc36bb928 to 0xc36bb970)
b920: c36bb9c0 00000000 c0126919 c0101228 c36bb9c0 b76d7730
b940: c36b8000 c36bb9a0 c3335b00 c01ce0d8 00000003 c36bba3c c36bb940 c36bb978
b960: c010e298 c011373c 60000013 ffffffff
[<c0100b0c>] (__irq_svc) from [<c011373c>] (unwind_frame+0x0/0x870)
[<c011373c>] (unwind_frame) from [<00000000>] (0x0)
The buggy address belongs to the page:
page:(ptrval) refcount:0 mapcount:0 mapping:00000000 index:0x0 pfn:0x636bb
flags: 0x0()
raw: 00000000 00000000 ef867764 00000000 00000000 00000000 ffffffff 00000000
page dumped because: kasan: bad access detected
addr c36bba90 is located in stack of task cat/163 at offset 48 in frame:
stack_trace_save+0x0/0xb4
this frame has 1 object:
[32, 48) 'trace'
Memory state around the buggy address:
c36bb980: f1 f1 f1 f1 00 04 f2 f2 00 00 f3 f3 00 00 00 00
c36bba00: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
>c36bba80: 00 00 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
^
c36bbb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
c36bbb80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
There is a same issue on x86 and has been resolved by the commit f7d27c35dd
("x86/mm, kasan: Silence KASAN warnings in get_wchan()").
The solution could be applied to arm architecture too.
Signed-off-by: Lin Yujun <linyujun809@huawei.com>
Reported-by: He Ying <heying24@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Add invalid input check expression when 'crashkernel=0' is specified
running kdump.
Signed-off-by: Austin Kim <austindh.kim@gmail.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
This set of changes removes tracehook.h, moves modification of all of
the ptrace fields inside of siglock to remove races, adds a missing
permission check to ptrace.c
The removal of tracehook.h is quite significant as it has been a major
source of confusion in recent years. Much of that confusion was
around task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled
making the semantics clearer).
For people who don't know tracehook.h is a vestiage of an attempt to
implement uprobes like functionality that was never fully merged, and
was later superseeded by uprobes when uprobes was merged. For many
years now we have been removing what tracehook functionaly a little
bit at a time. To the point where now anything left in tracehook.h is
some weird strange thing that is difficult to understand.
Eric W. Biederman (15):
ptrace: Move ptrace_report_syscall into ptrace.h
ptrace/arm: Rename tracehook_report_syscall report_syscall
ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
ptrace: Remove arch_syscall_{enter,exit}_tracehook
ptrace: Remove tracehook_signal_handler
task_work: Remove unnecessary include from posix_timers.h
task_work: Introduce task_work_pending
task_work: Call tracehook_notify_signal from get_signal on all architectures
task_work: Decouple TIF_NOTIFY_SIGNAL and task_work
signal: Move set_notify_signal and clear_notify_signal into sched/signal.h
resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume
resume_user_mode: Move to resume_user_mode.h
tracehook: Remove tracehook.h
ptrace: Move setting/clearing ptrace_message into ptrace_stop
ptrace: Return the signal to continue with from ptrace_stop
Jann Horn (1):
ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE
Yang Li (1):
ptrace: Remove duplicated include in ptrace.c
MAINTAINERS | 1 -
arch/Kconfig | 5 +-
arch/alpha/kernel/ptrace.c | 5 +-
arch/alpha/kernel/signal.c | 4 +-
arch/arc/kernel/ptrace.c | 5 +-
arch/arc/kernel/signal.c | 4 +-
arch/arm/kernel/ptrace.c | 12 +-
arch/arm/kernel/signal.c | 4 +-
arch/arm64/kernel/ptrace.c | 14 +--
arch/arm64/kernel/signal.c | 4 +-
arch/csky/kernel/ptrace.c | 5 +-
arch/csky/kernel/signal.c | 4 +-
arch/h8300/kernel/ptrace.c | 5 +-
arch/h8300/kernel/signal.c | 4 +-
arch/hexagon/kernel/process.c | 4 +-
arch/hexagon/kernel/signal.c | 1 -
arch/hexagon/kernel/traps.c | 6 +-
arch/ia64/kernel/process.c | 4 +-
arch/ia64/kernel/ptrace.c | 6 +-
arch/ia64/kernel/signal.c | 1 -
arch/m68k/kernel/ptrace.c | 5 +-
arch/m68k/kernel/signal.c | 4 +-
arch/microblaze/kernel/ptrace.c | 5 +-
arch/microblaze/kernel/signal.c | 4 +-
arch/mips/kernel/ptrace.c | 5 +-
arch/mips/kernel/signal.c | 4 +-
arch/nds32/include/asm/syscall.h | 2 +-
arch/nds32/kernel/ptrace.c | 5 +-
arch/nds32/kernel/signal.c | 4 +-
arch/nios2/kernel/ptrace.c | 5 +-
arch/nios2/kernel/signal.c | 4 +-
arch/openrisc/kernel/ptrace.c | 5 +-
arch/openrisc/kernel/signal.c | 4 +-
arch/parisc/kernel/ptrace.c | 7 +-
arch/parisc/kernel/signal.c | 4 +-
arch/powerpc/kernel/ptrace/ptrace.c | 8 +-
arch/powerpc/kernel/signal.c | 4 +-
arch/riscv/kernel/ptrace.c | 5 +-
arch/riscv/kernel/signal.c | 4 +-
arch/s390/include/asm/entry-common.h | 1 -
arch/s390/kernel/ptrace.c | 1 -
arch/s390/kernel/signal.c | 5 +-
arch/sh/kernel/ptrace_32.c | 5 +-
arch/sh/kernel/signal_32.c | 4 +-
arch/sparc/kernel/ptrace_32.c | 5 +-
arch/sparc/kernel/ptrace_64.c | 5 +-
arch/sparc/kernel/signal32.c | 1 -
arch/sparc/kernel/signal_32.c | 4 +-
arch/sparc/kernel/signal_64.c | 4 +-
arch/um/kernel/process.c | 4 +-
arch/um/kernel/ptrace.c | 5 +-
arch/x86/kernel/ptrace.c | 1 -
arch/x86/kernel/signal.c | 5 +-
arch/x86/mm/tlb.c | 1 +
arch/xtensa/kernel/ptrace.c | 5 +-
arch/xtensa/kernel/signal.c | 4 +-
block/blk-cgroup.c | 2 +-
fs/coredump.c | 1 -
fs/exec.c | 1 -
fs/io-wq.c | 6 +-
fs/io_uring.c | 11 +-
fs/proc/array.c | 1 -
fs/proc/base.c | 1 -
include/asm-generic/syscall.h | 2 +-
include/linux/entry-common.h | 47 +-------
include/linux/entry-kvm.h | 2 +-
include/linux/posix-timers.h | 1 -
include/linux/ptrace.h | 81 ++++++++++++-
include/linux/resume_user_mode.h | 64 ++++++++++
include/linux/sched/signal.h | 17 +++
include/linux/task_work.h | 5 +
include/linux/tracehook.h | 226 -----------------------------------
include/uapi/linux/ptrace.h | 2 +-
kernel/entry/common.c | 19 +--
kernel/entry/kvm.c | 9 +-
kernel/exit.c | 3 +-
kernel/livepatch/transition.c | 1 -
kernel/ptrace.c | 47 +++++---
kernel/seccomp.c | 1 -
kernel/signal.c | 62 +++++-----
kernel/task_work.c | 4 +-
kernel/time/posix-cpu-timers.c | 1 +
mm/memcontrol.c | 2 +-
security/apparmor/domain.c | 1 -
security/selinux/hooks.c | 1 -
85 files changed, 372 insertions(+), 495 deletions(-)
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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Merge tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull ptrace cleanups from Eric Biederman:
"This set of changes removes tracehook.h, moves modification of all of
the ptrace fields inside of siglock to remove races, adds a missing
permission check to ptrace.c
The removal of tracehook.h is quite significant as it has been a major
source of confusion in recent years. Much of that confusion was around
task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled making the
semantics clearer).
For people who don't know tracehook.h is a vestiage of an attempt to
implement uprobes like functionality that was never fully merged, and
was later superseeded by uprobes when uprobes was merged. For many
years now we have been removing what tracehook functionaly a little
bit at a time. To the point where anything left in tracehook.h was
some weird strange thing that was difficult to understand"
* tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
ptrace: Remove duplicated include in ptrace.c
ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE
ptrace: Return the signal to continue with from ptrace_stop
ptrace: Move setting/clearing ptrace_message into ptrace_stop
tracehook: Remove tracehook.h
resume_user_mode: Move to resume_user_mode.h
resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume
signal: Move set_notify_signal and clear_notify_signal into sched/signal.h
task_work: Decouple TIF_NOTIFY_SIGNAL and task_work
task_work: Call tracehook_notify_signal from get_signal on all architectures
task_work: Introduce task_work_pending
task_work: Remove unnecessary include from posix_timers.h
ptrace: Remove tracehook_signal_handler
ptrace: Remove arch_syscall_{enter,exit}_tracehook
ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
ptrace/arm: Rename tracehook_report_syscall report_syscall
ptrace: Move ptrace_report_syscall into ptrace.h
There are three sets of updates for 5.18 in the asm-generic tree:
- The set_fs()/get_fs() infrastructure gets removed for good. This
was already gone from all major architectures, but now we can
finally remove it everywhere, which loses some particularly
tricky and error-prone code.
There is a small merge conflict against a parisc cleanup, the
solution is to use their new version.
- The nds32 architecture ends its tenure in the Linux kernel. The
hardware is still used and the code is in reasonable shape, but
the mainline port is not actively maintained any more, as all
remaining users are thought to run vendor kernels that would never
be updated to a future release.
There are some obvious conflicts against changes to the removed
files.
- A series from Masahiro Yamada cleans up some of the uapi header
files to pass the compile-time checks.
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Merge tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic updates from Arnd Bergmann:
"There are three sets of updates for 5.18 in the asm-generic tree:
- The set_fs()/get_fs() infrastructure gets removed for good.
This was already gone from all major architectures, but now we can
finally remove it everywhere, which loses some particularly tricky
and error-prone code. There is a small merge conflict against a
parisc cleanup, the solution is to use their new version.
- The nds32 architecture ends its tenure in the Linux kernel.
The hardware is still used and the code is in reasonable shape, but
the mainline port is not actively maintained any more, as all
remaining users are thought to run vendor kernels that would never
be updated to a future release.
- A series from Masahiro Yamada cleans up some of the uapi header
files to pass the compile-time checks"
* tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (27 commits)
nds32: Remove the architecture
uaccess: remove CONFIG_SET_FS
ia64: remove CONFIG_SET_FS support
sh: remove CONFIG_SET_FS support
sparc64: remove CONFIG_SET_FS support
lib/test_lockup: fix kernel pointer check for separate address spaces
uaccess: generalize access_ok()
uaccess: fix type mismatch warnings from access_ok()
arm64: simplify access_ok()
m68k: fix access_ok for coldfire
MIPS: use simpler access_ok()
MIPS: Handle address errors for accesses above CPU max virtual user address
uaccess: add generic __{get,put}_kernel_nofault
nios2: drop access_ok() check from __put_user()
x86: use more conventional access_ok() definition
x86: remove __range_not_ok()
sparc64: add __{get,put}_kernel_nofault()
nds32: fix access_ok() checks in get/put_user
uaccess: fix nios2 and microblaze get_user_8()
sparc64: fix building assembly files
...
Updates for IRQ stacks and virtually mapped stack support for ARM from
the following pull requests, etc:
1) ARM: support for IRQ and vmap'ed stacks
This PR covers all the work related to implementing IRQ stacks and
vmap'ed stacks for all 32-bit ARM systems that are currently supported
by the Linux kernel, including RiscPC and Footbridge. It has been
submitted for review in three different waves:
- IRQ stacks support for v7 SMP systems [0],
- vmap'ed stacks support for v7 SMP systems[1],
- extending support for both IRQ stacks and vmap'ed stacks for all
remaining configurations, including v6/v7 SMP multiplatform kernels
and uniprocessor configurations including v7-M [2]
[0] https://lore.kernel.org/linux-arm-kernel/20211115084732.3704393-1-ardb@kernel.org/
[1] https://lore.kernel.org/linux-arm-kernel/20211122092816.2865873-1-ardb@kernel.org/
[2] https://lore.kernel.org/linux-arm-kernel/20211206164659.1495084-1-ardb@kernel.org/
2) ARM: support for IRQ and vmap'ed stacks [v6]
This tag covers the changes between the version of vmap'ed + IRQ stacks
support pulled into rmk/devel-stable [0] (which was dropped from v5.17
due to issues discovered too late in the cycle), and my v5 proposed for
the v5.18 cycle [1].
[0] git://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux.git arm-irq-and-vmap-stacks-for-rmk
[1] https://lore.kernel.org/linux-arm-kernel/20220124174744.1054712-1-ardb@kernel.org/
3) ARM: ftrace fixes and cleanups
Make all flavors of ftrace available on all builds, regardless of ISA
choice, unwinder choice or compiler:
- use ADD not POP where possible
- fix a couple of Thumb2 related issues
- enable HAVE_FUNCTION_GRAPH_FP_TEST for robustness
- enable the graph tracer with the EABI unwinder
- avoid clobbering frame pointer registers to make Clang happy
Link: https://lore.kernel.org/linux-arm-kernel/20220203082204.1176734-1-ardb@kernel.org/
4) Fixes for the above.
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Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:
"Updates for IRQ stacks and virtually mapped stack support, and ftrace:
- Support for IRQ and vmap'ed stacks
This covers all the work related to implementing IRQ stacks and
vmap'ed stacks for all 32-bit ARM systems that are currently
supported by the Linux kernel, including RiscPC and Footbridge. It
has been submitted for review in four different waves:
- IRQ stacks support for v7 SMP systems [0]
- vmap'ed stacks support for v7 SMP systems[1]
- extending support for both IRQ stacks and vmap'ed stacks for all
remaining configurations, including v6/v7 SMP multiplatform
kernels and uniprocessor configurations including v7-M [2]
- fixes and updates in [3]
- ftrace fixes and cleanups
Make all flavors of ftrace available on all builds, regardless of
ISA choice, unwinder choice or compiler [4]:
- use ADD not POP where possible
- fix a couple of Thumb2 related issues
- enable HAVE_FUNCTION_GRAPH_FP_TEST for robustness
- enable the graph tracer with the EABI unwinder
- avoid clobbering frame pointer registers to make Clang happy
- Fixes for the above"
[0] https://lore.kernel.org/linux-arm-kernel/20211115084732.3704393-1-ardb@kernel.org/
[1] https://lore.kernel.org/linux-arm-kernel/20211122092816.2865873-1-ardb@kernel.org/
[2] https://lore.kernel.org/linux-arm-kernel/20211206164659.1495084-1-ardb@kernel.org/
[3] https://lore.kernel.org/linux-arm-kernel/20220124174744.1054712-1-ardb@kernel.org/
[4] https://lore.kernel.org/linux-arm-kernel/20220203082204.1176734-1-ardb@kernel.org/
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (62 commits)
ARM: fix building NOMMU ARMv4/v5 kernels
ARM: unwind: only permit stack switch when unwinding call_with_stack()
ARM: Revert "unwind: dump exception stack from calling frame"
ARM: entry: fix unwinder problems caused by IRQ stacks
ARM: unwind: set frame.pc correctly for current-thread unwinding
ARM: 9184/1: return_address: disable again for CONFIG_ARM_UNWIND=y
ARM: 9183/1: unwind: avoid spurious warnings on bogus code addresses
Revert "ARM: 9144/1: forbid ftrace with clang and thumb2_kernel"
ARM: mach-bcm: disable ftrace in SMC invocation routines
ARM: cacheflush: avoid clobbering the frame pointer
ARM: kprobes: treat R7 as the frame pointer register in Thumb2 builds
ARM: ftrace: enable the graph tracer with the EABI unwinder
ARM: unwind: track location of LR value in stack frame
ARM: ftrace: enable HAVE_FUNCTION_GRAPH_FP_TEST
ARM: ftrace: avoid unnecessary literal loads
ARM: ftrace: avoid redundant loads or clobbering IP
ARM: ftrace: use trampolines to keep .init.text in branching range
ARM: ftrace: use ADD not POP to counter PUSH at entry
ARM: ftrace: ensure that ADR takes the Thumb bit into account
ARM: make get_current() and __my_cpu_offset() __always_inline
...
When building for Thumb2, the vectors make use of a local label. Sadly,
the Spectre BHB code also uses a local label with the same number which
results in the Thumb2 reference pointing at the wrong place. Fix this
by changing the number used for the Spectre BHB local label.
Fixes: b9baf5c8c5 ("ARM: Spectre-BHB workaround")
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit b6506981f8 ("ARM: unwind: support unwinding across multiple
stacks") updated the logic in the ARM unwinder to widen the bounds
within which SP is assumed to be valid, in order to allow the unwind to
traverse from the IRQ stack to the task stack. This is necessary, as
otherwise, unwinds started from the IRQ stack would terminate in the IRQ
exception handler, making stacktraces substantially less useful.
This turns out to be a mistake, as it breaks asynchronous unwinding
across exceptions, when the exception is taken before the stack frame is
consistent with the unwind info. For instance, in the following
backtrace:
...
generic_handle_arch_irq from call_with_stack+0x18/0x20
call_with_stack from __irq_svc+0x80/0x98
Exception stack(0xc7093e20 to 0xc7093e68)
3e20: b6a94a88 c7093ea0 00000008 00000000 c7093ea0 b7e127d0 00000051 c9220000
3e40: b6a94a88 b6a94a88 00000004 0002b000 0036b570 c7093e70 c040ca2c c0994a90
3e60: 20070013 ffffffff
__irq_svc from __copy_to_user_std+0x20/0x378
...
we need to apply the following unwind directives:
0xc099720c <__copy_to_user_std+0x1c>: @0xc295d1d4
Compact model index: 1
0x9b vsp = r11
0xb1 0x0d pop {r0, r2, r3}
0x84 0x81 pop {r4, r11, r14}
0xb0 finish
which tell us to switch to the frame pointer register R11 and proceed
with the unwind from that. However, having been interrupted 0x20 bytes
into the function:
c09971f0 <__copy_to_user_std>:
c09971f0: e59f3350 ldr r3, [pc, #848]
c09971f4: e243c001 sub ip, r3, #1
c09971f8: e05cc000 subs ip, ip, r0
c09971fc: 228cc001 addcs ip, ip, #1
c0997200: 205cc002 subscs ip, ip, r2
c0997204: 33a00000 movcc r0, #0
c0997208: e320f014 csdb
c099720c: e3a03000 mov r3, #0
c0997210: e92d481d push {r0, r2, r3, r4, fp, lr}
c0997214: e1a0b00d mov fp, sp
c0997218: e2522004 subs r2, r2, #4
the value for R11 recovered from the previous frame (__irq_svc) will be
a snapshot of its value before the exception was taken (0x0002b000),
which occurred at address __copy_to_user_std+0x20 (0xc0997210), when R11
had not been assigned its value yet.
This means we can never assume that the SP values recovered from the
stack or from the frame pointer are ever safe to use, given the need to
do asynchronous unwinding, and the only robust approach is to revert to
the previous approach, which is to derive bounds for SP based on the
initial value, and never update them.
We can make an exception, though: now that the IRQ stack switch is
guaranteed to occur in call_with_stack(), we can implement a special
case for this function, and use a different set of bounds based on the
knowledge that it will always unwind from R11 rather than SP. As
call_with_stack() is a hand-rolled assembly routine, this is guaranteed
to remain that way.
So let's do a partial revert of b6506981f8, and drop all manipulations
for sp_low and sp_high based on the information collected during the
unwind itself. To support call_with_stack(), set sp_low and sp_high
explicitly to values derived from R11 when we unwind that function.
The only downside is that, while unwinding an overflow of the vmap'ed
stack will work fine as before, we will no longer be able to produce a
backtrace that unwinds the overflow stack itself across the exception
that was raised due to the faulting access to the guard region. However,
this only affects exceptions caused by problems in the stack overflow
handling code itself, in which case the remaining backtrace is not that
relevant.
Fixes: b6506981f8 ("ARM: unwind: support unwinding across multiple stacks")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
After simplifying the stack switch code in the IRQ exception handler by
deferring the actual stack switch to call_with_stack(), we no longer
need to special case the way we dump the exception stack, since it will
always be at the top of whichever stack was active when the exception
was taken.
So revert this special handling for the ARM unwinder.
This reverts commit 4ab6827081.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
The IRQ stacks series made some changes to the unwinder, to permit
unwinding across different stacks. This is needed because otherwise, the
call stack would terminate at the point where the stack switch between
the task stack and the IRQ stack occurs, which would defeat any
diagnostics that rely on timer interrupts, such as RCU stall detection.
Unfortunately, getting the unwind annotations correct turns out to be
difficult, given that this now involves a frame pointer which needs to
point into the right location in the task stack when unwinding from the
IRQ stack. Getting this wrong for an exception handling routine results
in the stack pointer to be unwound from the wrong location, causing any
subsequent unwind attempts to cause all kinds of issues, as reported by
Naresh here [0].
So let's simplify this, by deferring the stack switch to
call_with_stack(), which already has the correct unwind annotations, and
removing all the complicated handling of the stack frame from the IRQ
exception entrypoint itself.
[0] https://lore.kernel.org/all/CA+G9fYtpy8VgK+ag6OsA9TDrwi5YGU4hu7GM8xwpO7v6LrCD4Q@mail.gmail.com/
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
When e.g. a WARN_ON() is encountered, we attempt to unwind the current
thread. To do this, we set frame.pc to unwind_backtrace, which means it
points at the beginning of the function. However, the rest of the state
is initialised from within the function, which means the function
prologue has already been run.
This can be confusing, and with a recent patch from Ard, can result in
the unwinder misbehaving if we want to be strict about the PC value.
If we correctly initialise the state so it is self-consistent (in other
words, set frame.pc to the location we are initialising it) then we
eliminate this confusion, and avoid possible future issues.
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Move set_notify_resume and tracehook_notify_resume into resume_user_mode.h.
While doing that rename tracehook_notify_resume to resume_user_mode_work.
Update all of the places that included tracehook.h for these functions to
include resume_user_mode.h instead.
Update all of the callers of tracehook_notify_resume to call
resume_user_mode_work.
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-12-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Rename tracehook_report_syscall_{entry,exit} to
ptrace_report_syscall_{entry,exit} and place them in ptrace.h
There is no longer any generic tracehook infractructure so make
these ptrace specific functions ptrace specific.
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-3-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Make the arm and arm64 code more concise and less confusing by
renaming the architecture specific tracehook_report_syscall to
report_syscall.
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-2-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
It was missing a semicolon.
Signed-off-by: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Fixes: 25875aa71d ("ARM: include unprivileged BPF status in Spectre V2 reporting").
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These patches add Spectre BHB migitations for the following Arm CPUs to
the 32-bit ARM kernels:
Cortex-A15
Cortex-A57
Cortex-A72
Cortex-A73
Cortex A75
Brahma B15
for CVE-2022-23960.
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Merge tag 'for-linus-bhb' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM spectre fixes from Russell King:
"ARM Spectre BHB mitigations.
These patches add Spectre BHB migitations for the following Arm CPUs
to the 32-bit ARM kernels:
- Cortex A15
- Cortex A57
- Cortex A72
- Cortex A73
- Cortex A75
- Brahma B15
for CVE-2022-23960"
* tag 'for-linus-bhb' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: include unprivileged BPF status in Spectre V2 reporting
ARM: Spectre-BHB workaround
ARM: use LOADADDR() to get load address of sections
ARM: early traps initialisation
ARM: report Spectre v2 status through sysfs
The mitigations for Spectre-BHB are only applied when an exception
is taken, but when unprivileged BPF is enabled, userspace can
load BPF programs that can be used to exploit the problem.
When unprivileged BPF is enabled, report the vulnerable status via
the spectre_v2 sysfs file.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Commit 41918ec82e ("ARM: ftrace: enable the graph tracer with the EABI
unwinder") removed the dummy version of return_address() that was
provided for the CONFIG_ARM_UNWIND=y case, on the assumption that the
removal of the kernel_text_address() call from unwind_frame() in the
preceding patch made it safe to do so.
However, this turns out not to be the case: Corentin reports warnings
about suspicious RCU usage and other strange behavior that seems to
originate in the stack unwinding that occurs in return_address().
Given that the function graph tracer (which is what these changes were
enabling for CONFIG_ARM_UNWIND=y builds) does not appear to care about
this distinction, let's revert return_address() to the old state.
Cc: Corentin Labbe <clabbe.montjoie@gmail.com>
Fixes: 41918ec82e ("ARM: ftrace: enable the graph tracer with the EABI unwinder")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reported-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Corentin reports that since commit 538b9265c0 ("ARM: unwind: track
location of LR value in stack frame"), numerous spurious warnings are
emitted into the kernel log:
[ 0.000000] unwind: Index not found c0f0c440
[ 0.000000] unwind: Index not found 00000000
[ 0.000000] unwind: Index not found c0f0c440
[ 0.000000] unwind: Index not found 00000000
This is due to the fact that the commit in question removes a check
whether the PC value in the unwound frame is actually a kernel text
address, on the assumption that such an address will not be associated
with valid unwind data to begin with, which is checked right after.
The reason for removing this check was that unwind_frame() will be
called by the ftrace graph tracer code, which means that it can no
longer be safely instrumented itself, or any code that it calls, as it
could cause infinite recursion.
In order to prevent the spurious diagnostics, let's add back the call to
kernel_text_address(), but this time, only call it if no unwind data
could be found for the address in question. This is more efficient for
the common successful case, and should avoid any unintended recursion,
considering that kernel_text_address() will only be called if no unwind
data was found.
Cc: Corentin Labbe <clabbe.montjoie@gmail.com>
Fixes: 538b9265c0 ("ARM: unwind: track location of LR value in stack frame")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Workaround the Spectre BHB issues for Cortex-A15, Cortex-A57,
Cortex-A72, Cortex-A73 and Cortex-A75. We also include Brahma B15 as
well to be safe, which is affected by Spectre V2 in the same ways as
Cortex-A15.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Provide a couple of helpers to copy the vectors and stubs, and also
to flush the copied vectors and stubs.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
As per other architectures, add support for reporting the Spectre
vulnerability status via sysfs CPU.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
On some architectures, access_ok() does not do any argument type
checking, so replacing the definition with a generic one causes
a few warnings for harmless issues that were never caught before.
Fix the ones that I found either through my own test builds or
that were reported by the 0-day bot.
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The kgdb code needs to register an undef hook for the Thumb UDF
instruction that will fault in order to be functional on Thumb2
platforms.
Reported-by: Johannes Stezenbach <js@sig21.net>
Tested-by: Johannes Stezenbach <js@sig21.net>
Fixes: 5cbad0ebf4 ("kgdb: support for ARCH=arm")
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Enable the function graph tracer in combination with the EABI unwinder,
so that Thumb2 builds or Clang ARM builds can make use of it.
This involves using the unwinder to locate the return address of an
instrumented function on the stack, so that it can be overridden and
made to refer to the ftrace handling routines that need to be called at
function return.
Given that for these builds, it is not guaranteed that the value of the
link register is stored on the stack, fall back to the stack slot that
will be used by the ftrace exit code to restore LR in the instrumented
function's execution context.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ftrace graph tracer needs to override the return address of an
instrumented function, in order to install a hook that gets invoked when
the function returns again.
Currently, we only support this when building for ARM using GCC with
frame pointers, as in this case, it is guaranteed that the function will
reload LR from [FP, #-4] in all cases, and we can simply pass that
address to the ftrace code.
In order to support this for configurations that rely on the EABI
unwinder, such as Thumb2 builds, make the unwinder keep track of the
address from which LR was unwound, permitting ftrace to make use of this
in a subsequent patch.
Drop the call to is_kernel_text_address(), which is problematic in terms
of ftrace recursion, given that it may be instrumented itself. The call
is redundant anyway, as no unwind directives will be found unless the PC
points to memory that is known to contain executable code.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Fix the frame pointer handling in the function graph tracer entry and
exit code so we can enable HAVE_FUNCTION_GRAPH_FP_TEST. Instead of using
FP directly (which will have different values between the entry and exit
pieces of the function graph tracer), use the value of SP at entry and
exit, as we can derive the former value from the frame pointer.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Avoid explicit literal loads and instead, use accessor macros that
generate the optimal sequence depending on the architecture revision
being targeted.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Tweak the ftrace return paths to avoid redundant loads of SP, as well as
unnecessary clobbering of IP.
This also fixes the inconsistency of using MOV to perform a function
return, which is sub-optimal on recent micro-architectures but more
importantly, does not perform an interworking return, unlike compiler
generated function returns in Thumb2 builds.
Let's fix this by popping PC from the stack like most ordinary code
does.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Kernel images that are large in comparison to the range of a direct
branch may fail to work as expected with ftrace, as patching a direct
branch to one of the core ftrace routines may not be possible from the
.init.text section, if it is emitted too far away from the normal .text
section.
This is more likely to affect Thumb2 builds, given that its range is
only -/+ 16 MiB (as opposed to ARM which has -/+ 32 MiB), but may occur
in either ISA.
To work around this, add a couple of trampolines to .init.text and
swap these in when the ftrace patching code is operating on callers in
.init.text.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The compiler emitted hook used for ftrace consists of a PUSH {LR} to
preserve the link register, followed by a branch-and-link (BL) to
__gnu_mount_nc. Dynamic ftrace patches away the latter to turn the
combined sequence into a NOP, using a POP {LR} instruction.
This is not necessary, since the link register does not get clobbered in
this case, and simply adding #4 to the stack pointer is sufficient, and
avoids a memory access that may take a few cycles to resolve depending
on the micro-architecture.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Using ADR to take the address of 'ftrace_stub' via a local label
produces an address that has the Thumb bit cleared, which means the
subsequent comparison is guaranteed to fail. Instead, use the badr
macro, which forces the Thumb bit to be set.
Fixes: a3ba87a614 ("ARM: 6316/1: ftrace: add Thumb-2 support")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Only SMP systems use the secondary startup path by definition, so there
is no need for SMP conditionals there.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Rework the vmalloc_seq handling so it can be used safely under SMP, as
we started using it to ensure that vmap'ed stacks are guaranteed to be
mapped by the active mm before switching to a task, and here we need to
ensure that changes to the page tables are visible to other CPUs when
they observe a change in the sequence count.
Since LPAE needs none of this, fold a check against it into the
vmalloc_seq counter check after breaking it out into a separate static
inline helper.
Given that vmap'ed stacks are now also supported on !SMP configurations,
let's drop the WARN() that could potentially now fire spuriously.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Avoid using R9 in the IRQ handler code, as the entry code uses it for
tsk, and expects it to remain untouched between the IRQ entry and exit
code.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Use the SMP_ON_UP patching framework to elide HWCAP_TLS tests from the
context switch and return to userspace code paths, as SMP systems are
guaranteed to have this h/w capability.
At the same time, omit the update of __entry_task if the system is
detected to be UP at runtime, as in that case, the value is never used.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Nathan reports the group relocations go out of range in pathological
cases such as allyesconfig kernels, which have little chance of actually
booting but are still used in validation.
So add a Kconfig symbol for this feature, and make it depend on
!COMPILE_TEST.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
When onlining a CPU, switch to swapper_pg_dir as soon as possible so
that it is guaranteed that the vmap'ed stack is mapped before it is
used.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Remove PDE_DATA() completely and replace it with pde_data().
[akpm@linux-foundation.org: fix naming clash in drivers/nubus/proc.c]
[akpm@linux-foundation.org: now fix it properly]
Link: https://lkml.kernel.org/r/20211124081956.87711-2-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alexey Gladkov <gladkov.alexey@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull signal/exit/ptrace updates from Eric Biederman:
"This set of changes deletes some dead code, makes a lot of cleanups
which hopefully make the code easier to follow, and fixes bugs found
along the way.
The end-game which I have not yet reached yet is for fatal signals
that generate coredumps to be short-circuit deliverable from
complete_signal, for force_siginfo_to_task not to require changing
userspace configured signal delivery state, and for the ptrace stops
to always happen in locations where we can guarantee on all
architectures that the all of the registers are saved and available on
the stack.
Removal of profile_task_ext, profile_munmap, and profile_handoff_task
are the big successes for dead code removal this round.
A bunch of small bug fixes are included, as most of the issues
reported were small enough that they would not affect bisection so I
simply added the fixes and did not fold the fixes into the changes
they were fixing.
There was a bug that broke coredumps piped to systemd-coredump. I
dropped the change that caused that bug and replaced it entirely with
something much more restrained. Unfortunately that required some
rebasing.
Some successes after this set of changes: There are few enough calls
to do_exit to audit in a reasonable amount of time. The lifetime of
struct kthread now matches the lifetime of struct task, and the
pointer to struct kthread is no longer stored in set_child_tid. The
flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is
removed. Issues where task->exit_code was examined with
signal->group_exit_code should been examined were fixed.
There are several loosely related changes included because I am
cleaning up and if I don't include them they will probably get lost.
The original postings of these changes can be found at:
https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.orghttps://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.orghttps://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org
I trimmed back the last set of changes to only the obviously correct
once. Simply because there was less time for review than I had hoped"
* 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits)
ptrace/m68k: Stop open coding ptrace_report_syscall
ptrace: Remove unused regs argument from ptrace_report_syscall
ptrace: Remove second setting of PT_SEIZED in ptrace_attach
taskstats: Cleanup the use of task->exit_code
exit: Use the correct exit_code in /proc/<pid>/stat
exit: Fix the exit_code for wait_task_zombie
exit: Coredumps reach do_group_exit
exit: Remove profile_handoff_task
exit: Remove profile_task_exit & profile_munmap
signal: clean up kernel-doc comments
signal: Remove the helper signal_group_exit
signal: Rename group_exit_task group_exec_task
coredump: Stop setting signal->group_exit_task
signal: Remove SIGNAL_GROUP_COREDUMP
signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process
signal: Make coredump handling explicit in complete_signal
signal: Have prepare_signal detect coredumps using signal->core_state
signal: Have the oom killer detect coredumps using signal->core_state
exit: Move force_uaccess back into do_exit
exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit
...
"Cleanup of the perf/kvm interaction."
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Merge tag 'perf_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Borislav Petkov:
"Cleanup of the perf/kvm interaction."
* tag 'perf_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Drop guest callback (un)register stubs
KVM: arm64: Drop perf.c and fold its tiny bits of code into arm.c
KVM: arm64: Hide kvm_arm_pmu_available behind CONFIG_HW_PERF_EVENTS=y
KVM: arm64: Convert to the generic perf callbacks
KVM: x86: Move Intel Processor Trace interrupt handler to vmx.c
KVM: Move x86's perf guest info callbacks to generic KVM
KVM: x86: More precisely identify NMI from guest when handling PMI
KVM: x86: Drop current_vcpu for kvm_running_vcpu + kvm_arch_vcpu variable
perf/core: Use static_call to optimize perf_guest_info_callbacks
perf: Force architectures to opt-in to guest callbacks
perf: Add wrappers for invoking guest callbacks
perf/core: Rework guest callbacks to prepare for static_call support
perf: Drop dead and useless guest "support" from arm, csky, nds32 and riscv
perf: Stop pretending that perf can handle multiple guest callbacks
KVM: x86: Register Processor Trace interrupt hook iff PT enabled in guest
KVM: x86: Register perf callbacks after calling vendor's hardware_setup()
perf: Protect perf_guest_cbs with RCU
- amba bus irq rework
- add kfence support
- support for Cortex M33 and M55 CPUs
- kbuild updates for decompressor
- let core code manage thread_info::cpu
- avoid unpredictable NOP encoding in decompressor
- reduce information printed in calltraces
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Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:
- amba bus irq rework
- add kfence support
- support for Cortex M33 and M55 CPUs
- kbuild updates for decompressor
- let core code manage thread_info::cpu
- avoid unpredictable NOP encoding in decompressor
- reduce information printed in calltraces
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: reduce the information printed in call traces
ARM: 9168/1: Add support for Cortex-M55 processor
ARM: 9167/1: Add support for Cortex-M33 processor
ARM: 9166/1: Support KFENCE for ARM
ARM: 9165/1: mm: Provide is_write_fault()
ARM: 9164/1: mm: Provide set_memory_valid()
ARM: 9163/1: amba: Move of_amba_device_decode_irq() into amba_probe()
ARM: 9162/1: amba: Kill sysfs attribute file of irq
ARM: 9161/1: mm: mark private VM_FAULT_X defines as vm_fault_t
ARM: 9159/1: decompressor: Avoid UNPREDICTABLE NOP encoding
ARM: 9158/1: leave it to core code to manage thread_info::cpu
ARM: 9154/1: decompressor: do not copy source files while building
accesing it in order to prevent any potential data races, and convert
all users to those new accessors
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Merge tag 'core_entry_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull thread_info flag accessor helper updates from Borislav Petkov:
"Add a set of thread_info.flags accessors which snapshot it before
accesing it in order to prevent any potential data races, and convert
all users to those new accessors"
* tag 'core_entry_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
powerpc: Snapshot thread flags
powerpc: Avoid discarding flags in system_call_exception()
openrisc: Snapshot thread flags
microblaze: Snapshot thread flags
arm64: Snapshot thread flags
ARM: Snapshot thread flags
alpha: Snapshot thread flags
sched: Snapshot thread flags
entry: Snapshot thread flags
x86: Snapshot thread flags
thread_info: Add helpers to snapshot thread flags
The Thumb2 version of the FP exception handling entry code treats the
register holding the CP number (R8) differently, resulting in the iWMMXT
CP number check to be incorrect.
Fix this by unifying the ARM and Thumb2 code paths, and switch the
order of the additions of the TI_USED_CP offset and the shifted CP
index.
Cc: <stable@vger.kernel.org>
Fixes: b86040a59f ("Thumb-2: Implementation of the unified start-up and exceptions code")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
__secondary_data used to reside in r7 around call to
PROCINFO_INITFUNC. After commit 95731b8ee6 ("ARM: 9059/1: cache-v7:
get rid of mini-stack") r7 is used as a scratch register, so we have
to reload __secondary_data before we setup the stack pointer.
Fixes: 95731b8ee6 ("ARM: 9059/1: cache-v7: get rid of mini-stack")
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
A while back, Linus complained about the numeric values printed by the
ARM backtracing code. Printing these values does not make sense if one
does not have access to the kernel ELF image (as is normally the case
when helping a third party on a mailing list), but if one does, they
can be very useful to find the code, rather than searching for the
function name, and then doing hex math to work out where the backtrace
entry is referring to.
Provide an option to control whether this information is included,
which will only be visible if EXPERT is enabled.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Since commit bcf9033e54 ("sched: move CPU field back into thread_info
if THREAD_INFO_IN_TASK=y"), the CPU field in thread_info went back to
being managed by the core code, so we no longer have to keep it in sync
in arch code.
While at it, mark THREAD_INFO_IN_TASK as done for ARM in the
documentation.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
There are two big uses of do_exit. The first is it's design use to be
the guts of the exit(2) system call. The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.
Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure. In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.
Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.
As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Enable support for IRQ stacks on !MMU, and add the code to the IRQ entry
path to switch to the IRQ stack if not running from it already.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
On UP systems, only a single task can be 'current' at the same time,
which means we can use a global variable to track it. This means we can
also enable THREAD_INFO_IN_TASK for those systems, as in that case,
thread_info is accessed via current rather than the other way around,
removing the need to store thread_info at the base of the task stack.
This, in turn, permits us to enable IRQ stacks and vmap'ed stacks on UP
systems as well.
To partially mitigate the performance overhead of this arrangement, use
a ADD/ADD/LDR sequence with the appropriate PC-relative group
relocations to load the value of current when needed. This means that
accessing current will still only require a single load as before,
avoiding the need for a literal to carry the address of the global
variable in each function. However, accessing thread_info will now
require this load as well.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Defer TPIDURO updates for user space until exit also for CPU_V6+SMP
configurations so that we can decide at runtime whether to use it to
carry the current pointer, provided that we are running on a CPU that
actually implements this register. This is needed for
THREAD_INFO_IN_TASK support for UP systems, which requires that all SMP
capable systems use the TPIDRURO based access to 'current' as the only
remaining alternative will be a global variable which only works on UP.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Permit the use of the TPIDRPRW system register for carrying the per-CPU
offset in generic SMP configurations that also target non-SMP capable
ARMv6 cores. This uses the SMP_ON_UP code patching framework to turn all
TPIDRPRW accesses into reads/writes of entry #0 in the __per_cpu_offset
array.
While at it, switch over some existing direct TPIDRPRW accesses in asm
code to invocations of a new helper that is patched in the same way when
necessary.
Note that CPU_V6+SMP without SMP_ON_UP results in a kernel that does not
boot on v6 CPUs without SMP extensions, so add this dependency to
Kconfig as well.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
We will be adding variable loads to various hot paths, so it makes sense
to add a helper macro that can load variables from asm code without the
use of literal pool entries. On v7 or later, we can simply use MOVW/MOVT
pairs, but on earlier cores, this requires a bit of hackery to emit a
instruction sequence that implements this using a sequence of ADD/LDR
instructions.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Add support for the R_ARM_ALU_PC_Gn_NC and R_ARM_LDR_PC_G2 group
relocations [0] so we can use them in modules. These will be used to
load the current task pointer from a global variable without having to
rely on a literal pool entry to carry the address of this variable,
which may have a significant negative impact on cache utilization for
variables that are used often and in many different places, as each
occurrence will result in a literal pool entry and therefore a line in
the D-cache.
[0] 'ELF for the ARM architecture'
https://github.com/ARM-software/abi-aa/releases
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Tweak the UP stack protector handling code so that the thread info
pointer is preserved in R7 until set_current is called. This is needed
for a subsequent patch that implements THREAD_INFO_IN_TASK and
set_current for UP as well.
This also means we will prefer the per-task protector on UP systems that
implement the thread ID registers, so tweak the preprocessor
conditionals to reflect this.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Rather then restructuring the ARMv7M entrly logic per TODO, just move
NVIC to GENERIC_IRQ_MULTI_HANDLER.
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
The last user of arch_irq_handler_default is gone now, so the
entry-macro-multi.S file and all references to mach/entry-macro.S can
be removed, as well as the asm_do_IRQ() entrypoint into the interrupt
handling routines implemented in C.
Note: The ARMv7-M entry still uses its own top-level IRQ entry, calling
nvic_handle_irq() from assembly. This could be changed to go through
generic_handle_arch_irq() as well, but it's unclear to me if there are
any benefits.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[ardb: keep irq_handler macro as it carries all the IRQ stack handling]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
iop32x uses the entry-macro.S file for both the IRQ entry and for
hooking into the arch_ret_to_user code path. This is done because the
cp6 registers have to be enabled before accessing any of the interrupt
controller registers but have to be disabled when running in user space.
There is also a lazy-enable logic in cp6.c, but during a hardirq, we
know it has to be enabled.
Both the cp6-enable code and the code to read the IRQ status can be
lifted into the normal generic_handle_arch_irq() path, but the
cp6-disable code has to remain in the user return code. As nothing
other than iop32x uses this hook, just open-code it there with an
ifdef for the platform that can eventually be removed when iop32x
has reached the end of its life.
The cp6-enable path in the IRQ entry has an extra cp_wait barrier that
the trap version does not have, but it is harmless to do it in both
cases to simplify the logic here at the cost of a few extra cycles
for the trap.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Wire up the generic support for managing task stack allocations via vmalloc,
and implement the entry code that detects whether we faulted because of a
stack overrun (or future stack overrun caused by pushing the pt_regs array)
While this adds a fair amount of tricky entry asm code, it should be
noted that it only adds a TST + branch to the svc_entry path. The code
implementing the non-trivial handling of the overflow stack is emitted
out-of-line into the .text section.
Since on ARM, we rely on do_translation_fault() to keep PMD level page
table entries that cover the vmalloc region up to date, we need to
ensure that we don't hit such a stale PMD entry when accessing the
stack. So we do a dummy read from the new stack while still running from
the old one on the context switch path, and bump the vmalloc_seq counter
when PMD level entries in the vmalloc range are modified, so that the MM
switch fetches the latest version of the entries.
Note that we need to increase the per-mode stack by 1 word, to gain some
space to stash a GPR until we know it is safe to touch the stack.
However, due to the cacheline alignment of the struct, this does not
actually increase the memory footprint of the struct stack array at all.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
The original Thumb-2 enablement patches updated the stack realignment
code in svc_entry to work around the lack of a STMIB instruction in
Thumb-2, by subtracting 4 from the frame size, inverting the sense of
the misaligment check, and changing to a STMIA instruction and a final
stack push of a 4 byte quantity that results in the stack becoming
aligned at the end of the sequence. It also pushes and pops R0 to the
stack in order to have a temp register that Thumb-2 allows in general
purpose ALU instructions, as TST using SP is not permitted.
Both are a bit problematic for vmap'ed stacks, as using the stack is
only permitted after we decide that we did not overflow the stack, or
have already switched to the overflow stack.
As for the alignment check: the current approach creates a corner case
where, if the initial SUB of SP ends up right at the start of the stack,
we will end up subtracting another 8 bytes and overflowing it. This
means we would need to add the overflow check *after* the SUB that
deliberately misaligns the stack. However, this would require us to keep
local state (i.e., whether we performed the subtract or not) across the
overflow check, but without any GPRs or stack available.
So let's switch to an approach where we don't use the stack, and where
the alignment check of the stack pointer occurs in the usual way, as
this is guaranteed not to result in overflow. This means we will be able
to do the overflow check first.
While at it, switch to R1 so the mode stack pointer in R0 remains
accessible.
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
The load-multiple instruction that essentially performs the switch_to
operation in ARM mode, by loading all callee save registers as well the
stack pointer and the program counter, is split into 3 separate loads
for Thumb-2, with the IP register used as a temporary to capture the
value of R4 before it gets overwritten.
We can clean this up a bit, by sticking with a single LDMIA instruction,
but one that pops SP and PC into IP and LR, respectively, and by using
ordinary move register and branch instructions to get those values into
SP and PC. This also allows us to move the set_current call closer to
the assignment of SP, reducing the window where those are mutually out
of sync. This is especially relevant for CONFIG_VMAP_STACK, which is
being introduced in a subsequent patch, where we need to issue a load
that might fault from the new stack while running from the old one, to
ensure that stale PMD entries in the VMALLOC space are synced up.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
When unwinding the stack from a stack overflow, we are likely to start
from a stack push instruction, given that this is the most common way to
grow the stack for compiler emitted code. This push instruction rarely
appears anywhere else than at offset 0x0 of the function, and if it
doesn't, the compiler tends to split up the unwind annotations, given
that the stack frame layout is apparently not the same throughout the
function.
This means that, in the general case, if the frame's PC points at the
first instruction covered by a certain unwind entry, there is no way the
stack frame that the unwind entry describes could have been created yet,
and so we are still on the stack frame of the caller in that case. So
treat this as a special case, and return with the new PC taken from the
frame's LR, without applying the unwind transformations to the virtual
register set.
This permits us to unwind the call stack on stack overflow when the
overflow was caused by a stack push on function entry.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Now that we have enabled IRQ stacks, any softIRQs that are handled over
the back of a hard IRQ will run from the IRQ stack as well. However, any
synchronous softirq processing that happens when re-enabling softIRQs
from task context will still execute on that task's stack.
Since any call to local_bh_enable() at any level in the task's call
stack may trigger a softIRQ processing run, which could potentially
cause a task stack overflow if the combined stack footprints exceed the
stack's size, let's run these synchronous invocations of do_softirq() on
the IRQ stack as well.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Now that we no longer rely on the stack pointer to access the current
task struct or thread info, we can implement support for IRQ stacks
cleanly as well.
Define a per-CPU IRQ stack and switch to this stack when taking an IRQ,
provided that we were not already using that stack in the interrupted
context. This is never the case for IRQs taken from user space, but ones
taken while running in the kernel could fire while one taken from user
space has not completed yet.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
The existing code that dumps the contents of the pt_regs structure
passed to __entry routines does so while unwinding the callee frame, and
dereferences the stack pointer as a struct pt_regs*. This will no longer
work when we enable support for IRQ or overflow stacks, because the
struct pt_regs may live on the task stack, while we are executing from
another stack.
The unwinder has access to this information, but only while unwinding
the calling frame. So let's combine the exception stack dumping code
with the handling of the calling frame as well. By printing it before
dumping the caller/callee addresses, the output order is preserved.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
The unwind info based stack unwinder will make its own call to
dump_mem() to dump the exception stack, so give it external linkage.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Implement support in the unwinder for dealing with multiple stacks.
This will be needed once we add support for IRQ stacks, or for the
overflow stack used by the vmap'ed stacks code.
This involves tracking the unwind opcodes that either update the virtual
stack pointer from another virtual register, or perform an explicit
subtract on the virtual stack pointer, and updating the low and high
bounds that we use to sanitize the stack pointer accordingly.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
This code appears to be no longer used so let's get rid of it.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Some thread flags can be set remotely, and so even when IRQs are disabled,
the flags can change under our feet. Generally this is unlikely to cause a
problem in practice, but it is somewhat unsound, and KCSAN will
legitimately warn that there is a data race.
To avoid such issues, a snapshot of the flags has to be taken prior to
using them. Some places already use READ_ONCE() for that, others do not.
Convert them all to the new flag accessor helpers.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Link: https://lore.kernel.org/r/20211129130653.2037928-6-mark.rutland@arm.com
Drop "support" for guest callbacks from architectures that don't implement
the guest callbacks. Future patches will convert the callbacks to
static_call; rather than churn a bunch of arch code (that was presumably
copy+pasted from x86), remove it wholesale as it's useless and at best
wasting cycles.
A future patch will also add a Kconfig to force architcture to opt into
the callbacks to make it more difficult for uses "support" to sneak in in
the future.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lore.kernel.org/r/20211111020738.2512932-6-seanjc@google.com
Protect perf_guest_cbs with RCU to fix multiple possible errors. Luckily,
all paths that read perf_guest_cbs already require RCU protection, e.g. to
protect the callback chains, so only the direct perf_guest_cbs touchpoints
need to be modified.
Bug #1 is a simple lack of WRITE_ONCE/READ_ONCE behavior to ensure
perf_guest_cbs isn't reloaded between a !NULL check and a dereference.
Fixed via the READ_ONCE() in rcu_dereference().
Bug #2 is that on weakly-ordered architectures, updates to the callbacks
themselves are not guaranteed to be visible before the pointer is made
visible to readers. Fixed by the smp_store_release() in
rcu_assign_pointer() when the new pointer is non-NULL.
Bug #3 is that, because the callbacks are global, it's possible for
readers to run in parallel with an unregisters, and thus a module
implementing the callbacks can be unloaded while readers are in flight,
resulting in a use-after-free. Fixed by a synchronize_rcu() call when
unregistering callbacks.
Bug #1 escaped notice because it's extremely unlikely a compiler will
reload perf_guest_cbs in this sequence. perf_guest_cbs does get reloaded
for future derefs, e.g. for ->is_user_mode(), but the ->is_in_guest()
guard all but guarantees the consumer will win the race, e.g. to nullify
perf_guest_cbs, KVM has to completely exit the guest and teardown down
all VMs before KVM start its module unload / unregister sequence. This
also makes it all but impossible to encounter bug #3.
Bug #2 has not been a problem because all architectures that register
callbacks are strongly ordered and/or have a static set of callbacks.
But with help, unloading kvm_intel can trigger bug #1 e.g. wrapping
perf_guest_cbs with READ_ONCE in perf_misc_flags() while spamming
kvm_intel module load/unload leads to:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP
CPU: 6 PID: 1825 Comm: stress Not tainted 5.14.0-rc2+ #459
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
RIP: 0010:perf_misc_flags+0x1c/0x70
Call Trace:
perf_prepare_sample+0x53/0x6b0
perf_event_output_forward+0x67/0x160
__perf_event_overflow+0x52/0xf0
handle_pmi_common+0x207/0x300
intel_pmu_handle_irq+0xcf/0x410
perf_event_nmi_handler+0x28/0x50
nmi_handle+0xc7/0x260
default_do_nmi+0x6b/0x170
exc_nmi+0x103/0x130
asm_exc_nmi+0x76/0xbf
Fixes: 39447b386c ("perf: Enhance perf to allow for guest statistic collection from host")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211111020738.2512932-2-seanjc@google.com
- Convert /reserved-memory bindings to schemas
- Convert a bunch of NFC bindings to schemas
- Convert bindings to schema: Xilinx USB, Freescale DDR controller, Arm
CCI-400, UBlox Neo-6M, 1-Wire GPIO, MSI controller, ASpeed LPC, OMAP
and Inside-Secure HWRNG, register-bit-led, OV5640, Silead GSL1680,
Elan ekth3000, Marvell bluetooth, TI wlcore, TI bluetooth, ESP ESP8089,
tlm,trusted-foundations, Microchip cap11xx, Ralink SoCs and boards,
and TI sysc
- New binding schemas for: msi-ranges, Aspeed UART routing controller,
palmbus, Xylon LogiCVC display controller, Mediatek's MT7621 SDRAM
memory controller, and Apple M1 PCIe host
- Run schema checks for %.dtb targets
- Improve build time when using DT_SCHEMA_FILES
- Improve error message when dtschema is not found
- Various doc reference fixes in MAINTAINERS
- Convert architectures to common CPU h/w ID parsing function
of_get_cpu_hwid().
- Allow for empty NUMA node IDs which may be hotplugged
- Cleanup of __fdt_scan_reserved_mem()
- Constify device_node parameters
- Update dtc to upstream v1.6.1-19-g0a3a9d3449c8. Adds new checks
'node_name_vs_property_name' and 'interrupt_map'.
- Enable dtc 'unit_address_format' warning by default
- Fix unittest EXPECT text for gpio hog errors
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Merge tag 'devicetree-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull devicetree updates from Rob Herring:
- Convert /reserved-memory bindings to schemas
- Convert a bunch of NFC bindings to schemas
- Convert bindings to schema: Xilinx USB, Freescale DDR controller, Arm
CCI-400, UBlox Neo-6M, 1-Wire GPIO, MSI controller, ASpeed LPC, OMAP
and Inside-Secure HWRNG, register-bit-led, OV5640, Silead GSL1680,
Elan ekth3000, Marvell bluetooth, TI wlcore, TI bluetooth, ESP
ESP8089, tlm,trusted-foundations, Microchip cap11xx, Ralink SoCs and
boards, and TI sysc
- New binding schemas for: msi-ranges, Aspeed UART routing controller,
palmbus, Xylon LogiCVC display controller, Mediatek's MT7621 SDRAM
memory controller, and Apple M1 PCIe host
- Run schema checks for %.dtb targets
- Improve build time when using DT_SCHEMA_FILES
- Improve error message when dtschema is not found
- Various doc reference fixes in MAINTAINERS
- Convert architectures to common CPU h/w ID parsing function
of_get_cpu_hwid().
- Allow for empty NUMA node IDs which may be hotplugged
- Cleanup of __fdt_scan_reserved_mem()
- Constify device_node parameters
- Update dtc to upstream v1.6.1-19-g0a3a9d3449c8. Adds new checks
'node_name_vs_property_name' and 'interrupt_map'.
- Enable dtc 'unit_address_format' warning by default
- Fix unittest EXPECT text for gpio hog errors
* tag 'devicetree-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (97 commits)
dt-bindings: net: ti,bluetooth: Document default max-speed
dt-bindings: pci: rcar-pci-ep: Document r8a7795
dt-bindings: net: qcom,ipa: IPA does support up to two iommus
of/fdt: Remove of_scan_flat_dt() usage for __fdt_scan_reserved_mem()
of: unittest: document intentional interrupt-map provider build warning
of: unittest: fix EXPECT text for gpio hog errors
of/unittest: Disable new dtc node_name_vs_property_name and interrupt_map warnings
scripts/dtc: Update to upstream version v1.6.1-19-g0a3a9d3449c8
dt-bindings: arm: firmware: tlm,trusted-foundations: Convert txt bindings to yaml
dt-bindings: display: tilcd: Fix endpoint addressing in example
dt-bindings: input: microchip,cap11xx: Convert txt bindings to yaml
dt-bindings: ufs: exynos-ufs: add exynosautov9 compatible
dt-bindings: ufs: exynos-ufs: add io-coherency property
dt-bindings: mips: convert Ralink SoCs and boards to schema
dt-bindings: display: xilinx: Fix example with psgtr
dt-bindings: net: nfc: nxp,pn544: Convert txt bindings to yaml
dt-bindings: Add a help message when dtschema tools are missing
dt-bindings: bus: ti-sysc: Update to use yaml binding
dt-bindings: sram: Allow numbers in sram region node name
dt-bindings: display: Document the Xylon LogiCVC display controller
...
- kprobes: Restructured stack unwinder to show properly on x86 when a stack
dump happens from a kretprobe callback.
- Fix to bootconfig parsing
- Have tracefs allow owner and group permissions by default (only denying
others). There's been pressure to allow non root to tracefs in a
controlled fashion, and using groups is probably the safest.
- Bootconfig memory managament updates.
- Bootconfig clean up to have the tools directory be less dependent on
changes in the kernel tree.
- Allow perf to be traced by function tracer.
- Rewrite of function graph tracer to be a callback from the function tracer
instead of having its own trampoline (this change will happen on an arch
by arch basis, and currently only x86_64 implements it).
- Allow multiple direct trampolines (bpf hooks to functions) be batched
together in one synchronization.
- Allow histogram triggers to add variables that can perform calculations
against the event's fields.
- Use the linker to determine architecture callbacks from the ftrace
trampoline to allow for proper parameter prototypes and prevent warnings
from the compiler.
- Extend histogram triggers to key off of variables.
- Have trace recursion use bit magic to determine preempt context over if
branches.
- Have trace recursion disable preemption as all use cases do anyway.
- Added testing for verification of tracing utilities.
- Various small clean ups and fixes.
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Merge tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
- kprobes: Restructured stack unwinder to show properly on x86 when a
stack dump happens from a kretprobe callback.
- Fix to bootconfig parsing
- Have tracefs allow owner and group permissions by default (only
denying others). There's been pressure to allow non root to tracefs
in a controlled fashion, and using groups is probably the safest.
- Bootconfig memory managament updates.
- Bootconfig clean up to have the tools directory be less dependent on
changes in the kernel tree.
- Allow perf to be traced by function tracer.
- Rewrite of function graph tracer to be a callback from the function
tracer instead of having its own trampoline (this change will happen
on an arch by arch basis, and currently only x86_64 implements it).
- Allow multiple direct trampolines (bpf hooks to functions) be batched
together in one synchronization.
- Allow histogram triggers to add variables that can perform
calculations against the event's fields.
- Use the linker to determine architecture callbacks from the ftrace
trampoline to allow for proper parameter prototypes and prevent
warnings from the compiler.
- Extend histogram triggers to key off of variables.
- Have trace recursion use bit magic to determine preempt context over
if branches.
- Have trace recursion disable preemption as all use cases do anyway.
- Added testing for verification of tracing utilities.
- Various small clean ups and fixes.
* tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (101 commits)
tracing/histogram: Fix semicolon.cocci warnings
tracing/histogram: Fix documentation inline emphasis warning
tracing: Increase PERF_MAX_TRACE_SIZE to handle Sentinel1 and docker together
tracing: Show size of requested perf buffer
bootconfig: Initialize ret in xbc_parse_tree()
ftrace: do CPU checking after preemption disabled
ftrace: disable preemption when recursion locked
tracing/histogram: Document expression arithmetic and constants
tracing/histogram: Optimize division by a power of 2
tracing/histogram: Covert expr to const if both operands are constants
tracing/histogram: Simplify handling of .sym-offset in expressions
tracing: Fix operator precedence for hist triggers expression
tracing: Add division and multiplication support for hist triggers
tracing: Add support for creating hist trigger variables from literal
selftests/ftrace: Stop tracing while reading the trace file by default
MAINTAINERS: Update KPROBES and TRACING entries
test_kprobes: Move it from kernel/ to lib/
docs, kprobes: Remove invalid URL and add new reference
samples/kretprobes: Fix return value if register_kretprobe() failed
lib/bootconfig: Fix the xbc_get_info kerneldoc
...
- Revert the printk format based wchan() symbol resolution as it can leak
the raw value in case that the symbol is not resolvable.
- Make wchan() more robust and work with all kind of unwinders by
enforcing that the task stays blocked while unwinding is in progress.
- Prevent sched_fork() from accessing an invalid sched_task_group
- Improve asymmetric packing logic
- Extend scheduler statistics to RT and DL scheduling classes and add
statistics for bandwith burst to the SCHED_FAIR class.
- Properly account SCHED_IDLE entities
- Prevent a potential deadlock when initial priority is assigned to a
newly created kthread. A recent change to plug a race between cpuset and
__sched_setscheduler() introduced a new lock dependency which is now
triggered. Break the lock dependency chain by moving the priority
assignment to the thread function.
- Fix the idle time reporting in /proc/uptime for NOHZ enabled systems.
- Improve idle balancing in general and especially for NOHZ enabled
systems.
- Provide proper interfaces for live patching so it does not have to
fiddle with scheduler internals.
- Add cluster aware scheduling support.
- A small set of tweaks for RT (irqwork, wait_task_inactive(), various
scheduler options and delaying mmdrop)
- The usual small tweaks and improvements all over the place
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Merge tag 'sched-core-2021-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Thomas Gleixner:
- Revert the printk format based wchan() symbol resolution as it can
leak the raw value in case that the symbol is not resolvable.
- Make wchan() more robust and work with all kind of unwinders by
enforcing that the task stays blocked while unwinding is in progress.
- Prevent sched_fork() from accessing an invalid sched_task_group
- Improve asymmetric packing logic
- Extend scheduler statistics to RT and DL scheduling classes and add
statistics for bandwith burst to the SCHED_FAIR class.
- Properly account SCHED_IDLE entities
- Prevent a potential deadlock when initial priority is assigned to a
newly created kthread. A recent change to plug a race between cpuset
and __sched_setscheduler() introduced a new lock dependency which is
now triggered. Break the lock dependency chain by moving the priority
assignment to the thread function.
- Fix the idle time reporting in /proc/uptime for NOHZ enabled systems.
- Improve idle balancing in general and especially for NOHZ enabled
systems.
- Provide proper interfaces for live patching so it does not have to
fiddle with scheduler internals.
- Add cluster aware scheduling support.
- A small set of tweaks for RT (irqwork, wait_task_inactive(), various
scheduler options and delaying mmdrop)
- The usual small tweaks and improvements all over the place
* tag 'sched-core-2021-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (69 commits)
sched/fair: Cleanup newidle_balance
sched/fair: Remove sysctl_sched_migration_cost condition
sched/fair: Wait before decaying max_newidle_lb_cost
sched/fair: Skip update_blocked_averages if we are defering load balance
sched/fair: Account update_blocked_averages in newidle_balance cost
x86: Fix __get_wchan() for !STACKTRACE
sched,x86: Fix L2 cache mask
sched/core: Remove rq_relock()
sched: Improve wake_up_all_idle_cpus() take #2
irq_work: Also rcuwait for !IRQ_WORK_HARD_IRQ on PREEMPT_RT
irq_work: Handle some irq_work in a per-CPU thread on PREEMPT_RT
irq_work: Allow irq_work_sync() to sleep if irq_work() no IRQ support.
sched/rt: Annotate the RT balancing logic irqwork as IRQ_WORK_HARD_IRQ
sched: Add cluster scheduler level for x86
sched: Add cluster scheduler level in core and related Kconfig for ARM64
topology: Represent clusters of CPUs within a die
sched: Disable -Wunused-but-set-variable
sched: Add wrapper for get_wchan() to keep task blocked
x86: Fix get_wchan() to support the ORC unwinder
proc: Use task_is_running() for wchan in /proc/$pid/stat
...
Core changes:
- Prevent a potential deadlock when initial priority is assigned to a
newly created interrupt thread. A recent change to plug a race between
cpuset and __sched_setscheduler() introduced a new lock dependency
which is now triggered. Break the lock dependency chain by moving the
priority assignment to the thread function.
- A couple of small updates to make the irq core RT safe.
- Confine the irq_cpu_online/offline() API to the only left unfixable
user Cavium Octeon so that it does not grow new usage.
- A small documentation update
Driver changes:
- A large cross architecture rework to move irq_enter/exit() into the
architecture code to make addressing the NOHZ_FULL/RCU issues simpler.
- The obligatory new irq chip driver for Microchip EIC
- Modularize a few irq chip drivers
- Expand usage of devm_*() helpers throughout the driver code
- The usual small fixes and improvements all over the place
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Merge tag 'irq-core-2021-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
"Updates for the interrupt subsystem:
Core changes:
- Prevent a potential deadlock when initial priority is assigned to a
newly created interrupt thread. A recent change to plug a race
between cpuset and __sched_setscheduler() introduced a new lock
dependency which is now triggered. Break the lock dependency chain
by moving the priority assignment to the thread function.
- A couple of small updates to make the irq core RT safe.
- Confine the irq_cpu_online/offline() API to the only left unfixable
user Cavium Octeon so that it does not grow new usage.
- A small documentation update
Driver changes:
- A large cross architecture rework to move irq_enter/exit() into the
architecture code to make addressing the NOHZ_FULL/RCU issues
simpler.
- The obligatory new irq chip driver for Microchip EIC
- Modularize a few irq chip drivers
- Expand usage of devm_*() helpers throughout the driver code
- The usual small fixes and improvements all over the place"
* tag 'irq-core-2021-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
h8300: Fix linux/irqchip.h include mess
dt-bindings: irqchip: renesas-irqc: Document r8a774e1 bindings
MIPS: irq: Avoid an unused-variable error
genirq: Hide irq_cpu_{on,off}line() behind a deprecated option
irqchip/mips-gic: Get rid of the reliance on irq_cpu_online()
MIPS: loongson64: Drop call to irq_cpu_offline()
irq: remove handle_domain_{irq,nmi}()
irq: remove CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY
irq: riscv: perform irqentry in entry code
irq: openrisc: perform irqentry in entry code
irq: csky: perform irqentry in entry code
irq: arm64: perform irqentry in entry code
irq: arm: perform irqentry in entry code
irq: add a (temporary) CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY
irq: nds32: avoid CONFIG_HANDLE_DOMAIN_IRQ
irq: arc: avoid CONFIG_HANDLE_DOMAIN_IRQ
irq: add generic_handle_arch_irq()
irq: unexport handle_irq_desc()
irq: simplify handle_domain_{irq,nmi}()
irq: mips: simplify do_domain_IRQ()
...
- Fix clang-related relocation warning in futex code
- Fix incorrect use of get_kernel_nofault()
- Fix bad code generation in __get_user_check() when kasan is enabled
- Ensure TLB function table is correctly aligned
- Remove duplicated string function definitions in decompressor
- Fix link-time orphan section warnings
- Fix old-style function prototype for arch_init_kprobes()
- Only warn about XIP address when not compile testing
- Handle BE32 big endian for keystone2 remapping
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Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM fixes from Russell King:
- Fix clang-related relocation warning in futex code
- Fix incorrect use of get_kernel_nofault()
- Fix bad code generation in __get_user_check() when kasan is enabled
- Ensure TLB function table is correctly aligned
- Remove duplicated string function definitions in decompressor
- Fix link-time orphan section warnings
- Fix old-style function prototype for arch_init_kprobes()
- Only warn about XIP address when not compile testing
- Handle BE32 big endian for keystone2 remapping
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 9148/1: handle CONFIG_CPU_ENDIAN_BE32 in arch/arm/kernel/head.S
ARM: 9141/1: only warn about XIP address when not compile testing
ARM: 9139/1: kprobes: fix arch_init_kprobes() prototype
ARM: 9138/1: fix link warning with XIP + frame-pointer
ARM: 9134/1: remove duplicate memcpy() definition
ARM: 9133/1: mm: proc-macros: ensure *_tlb_fns are 4B aligned
ARM: 9132/1: Fix __get_user_check failure with ARM KASAN images
ARM: 9125/1: fix incorrect use of get_kernel_nofault()
ARM: 9122/1: select HAVE_FUTEX_CMPXCHG
A lot of randconfig builds end up not selecting any machine type at
all. This is generally fine for the purpose of compile testing, but
of course it means that the kernel is not usable on actual hardware,
and it causes a warning about this fact.
As most of the build bots now force-enable CONFIG_COMPILE_TEST for
randconfig builds, use that as a guard to control whether we warn
on this type of broken configuration.
We could do the same for the missing-cpu-type warning, but those
configurations fail to build much earlier.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
My intel-ixp42x-welltech-epbx100 no longer boot since 4.14.
This is due to commit 463dbba4d1 ("ARM: 9104/2: Fix Keystone 2 kernel
mapping regression")
which forgot to handle CONFIG_CPU_ENDIAN_BE32 as possible BE config.
Suggested-by: Krzysztof Hałasa <khalasa@piap.pl>
Fixes: 463dbba4d1 ("ARM: 9104/2: Fix Keystone 2 kernel mapping regression")
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
In preparation for removing HANDLE_DOMAIN_IRQ_IRQENTRY, have arch/arm
perform all the irqentry accounting in its entry code.
For configurations with CONFIG_GENERIC_IRQ_MULTI_HANDLER, we can use
generic_handle_arch_irq(). Other than asm_do_IRQ(), all C calls to
handle_IRQ() are from irqchip handlers which will be called from
generic_handle_arch_irq(), so to avoid double accounting IRQ entry, the
entry logic is moved from handle_IRQ() into asm_do_IRQ().
For ARMv7M the entry assembly is tightly coupled with the NVIC irqchip, and
while the entry code should logically live under arch/arm/, moving the
entry logic there makes things more convoluted. So for now, place the
entry logic in the NVIC irqchip, but separated into a separate
function to make the split of responsibility clear.
For all other configurations without CONFIG_GENERIC_IRQ_MULTI_HANDLER,
IRQ entry is already handled in arch code, and requires no changes.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Since the kretprobe replaces the function return address with
the kretprobe_trampoline on the stack, arm unwinder shows it
instead of the correct return address.
This finds the correct return address from the per-task
kretprobe_instances list and verify it is in between the
caller fp and callee fp.
Note that this supports both GCC and clang if CONFIG_FRAME_POINTER=y
and CONFIG_ARM_UNWIND=n. For the ARM unwinder, this is still
not working correctly.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Currently the stacktrace on clang compiled arm kernel uses the 'lr'
register to find the first frame address from pt_regs. However, that
is wrong after calling another function, because the 'lr' register
is used by 'bl' instruction and never be recovered.
As same as gcc arm kernel, directly use the frame pointer (r11) of
the pt_regs to find the first frame address.
Note that this fixes kretprobe stacktrace issue only with
CONFIG_UNWINDER_FRAME_POINTER=y. For the CONFIG_UNWINDER_ARM,
we need another fix.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Replace the open coded parsing of CPU nodes' 'reg' property with
of_get_cpu_hwid().
This change drops an error message for missing 'reg' property, but that
should not be necessary as the DT tools will ensure 'reg' is present.
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20211006164332.1981454-3-robh@kernel.org
In randconfig builds, we sometimes come across this warning:
arm-linux-gnueabi-ld: XIP start address may cause MPU programming issues
While this is helpful for actual systems to figure out why it
fails, the warning does not provide any benefit for build testing,
so guard it in a check for CONFIG_COMPILE_TEST, which is usually
set on randconfig builds.
Fixes: 216218308c ("ARM: 8713/1: NOMMU: Support MPU in XIP configuration")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
When frame pointers are used instead of the ARM unwinder,
and the kernel is built using clang with an external assembler
and CONFIG_XIP_KERNEL, every file produces two warnings
like:
arm-linux-gnueabi-ld: warning: orphan section `.ARM.extab' from `net/mac802154/util.o' being placed in section `.ARM.extab'
arm-linux-gnueabi-ld: warning: orphan section `.ARM.exidx' from `net/mac802154/util.o' being placed in section `.ARM.exidx'
The same fix was already merged for the normal (non-XIP)
linker script, with a longer description.
Fixes: c39866f268 ("arm/build: Always handle .ARM.exidx and .ARM.extab sections")
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Commit 344179fc7e ("ARM: 9106/1: traps: use get_kernel_nofault instead
of set_fs()") replaced an occurrence of __get_user() with
get_kernel_nofault(), but inverted the sense of the conditional in the
process, resulting in no values to be printed at all.
I.e., every exception stack now looks like this:
Exception stack(0xc18d1fb0 to 0xc18d1ff8)
1fa0: ???????? ???????? ???????? ????????
1fc0: ???????? ???????? ???????? ???????? ???????? ???????? ???????? ????????
1fe0: ???????? ???????? ???????? ???????? ???????? ????????
which is rather unhelpful.
Fixes: 344179fc7e ("ARM: 9106/1: traps: use get_kernel_nofault instead of set_fs()")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Commit 344179fc7e ("ARM: 9106/1: traps: use get_kernel_nofault instead
of set_fs()") replaced an occurrence of __get_user() with
get_kernel_nofault(), but inverted the sense of the conditional in the
process, resulting in no values to be printed at all.
I.e., every exception stack now looks like this:
Exception stack(0xc18d1fb0 to 0xc18d1ff8)
1fa0: ???????? ???????? ???????? ????????
1fc0: ???????? ???????? ???????? ???????? ???????? ???????? ???????? ????????
1fe0: ???????? ???????? ???????? ???????? ???????? ????????
which is rather unhelpful.
Fixes: 344179fc7e ("ARM: 9106/1: traps: use get_kernel_nofault instead of set_fs()")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Having a stable wchan means the process must be blocked and for it to
stay that way while performing stack unwinding.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [arm]
Tested-by: Mark Rutland <mark.rutland@arm.com> [arm64]
Link: https://lkml.kernel.org/r/20211008111626.332092234@infradead.org
Most of ARCHs use empty ftrace_dyn_arch_init(), introduce a weak common
ftrace_dyn_arch_init() to cleanup them.
Link: https://lkml.kernel.org/r/20210909090216.1955240-1-o451686892@gmail.com
Acked-by: Heiko Carstens <hca@linux.ibm.com> (s390)
Acked-by: Helge Deller <deller@gmx.de> (parisc)
Signed-off-by: Weizhao Ouyang <o451686892@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Now that we no longer rely on thread_info living at the base of the task
stack to be able to access the 'current' pointer, we can wire up the
generic support for moving thread_info into the task struct itself.
Note that this requires us to update the cpu field in thread_info
explicitly, now that the core code no longer does so. Ideally, we would
switch the percpu code to access the cpu field in task_struct instead,
but this unleashes #include circular dependency hell.
Co-developed-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Now that the user space TLS register is assigned on every return to user
space, we can use it to keep the 'current' pointer while running in the
kernel. This removes the need to access it via thread_info, which is
located at the base of the stack, but will be moved out of there in a
subsequent patch.
Use the __builtin_thread_pointer() helper when available - this will
help GCC understand that reloading the value within the same function is
not necessary, even when using the per-task stack protector (which also
generates accesses via the TLS register). For example, the generated
code below loads TPIDRURO only once, and uses it to access both the
stack canary and the preempt_count fields.
<do_one_initcall>:
e92d 41f0 stmdb sp!, {r4, r5, r6, r7, r8, lr}
ee1d 4f70 mrc 15, 0, r4, cr13, cr0, {3}
4606 mov r6, r0
b094 sub sp, #80 ; 0x50
f8d4 34e8 ldr.w r3, [r4, #1256] ; 0x4e8 <- stack canary
9313 str r3, [sp, #76] ; 0x4c
f8d4 8004 ldr.w r8, [r4, #4] <- preempt count
Co-developed-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
To prepare for a subsequent patch that stores the current task pointer
in the user space TLS register while running in the kernel, modify the
set_tls and switch_tls routines not to touch the register directly, and
update the return to user space code to load the correct value.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
This avoids needing to compute the task pointer in this function, which
will no longer be possible once we move thread_info off the stack.
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
We will be enabling THREAD_INFO_IN_TASK support for ARM, which means
that we can no longer load the stack canary value by masking the stack
pointer and taking the copy that lives in thread_info. Instead, we will
be able to load it from the task_struct directly, by using the TPIDRURO
register which will hold the current task pointer when
THREAD_INFO_IN_TASK is in effect. This is much more straight-forward,
and allows us to declutter this code a bit while at it.
Note that this means that ARMv6 (non-v6K) SMP systems can no longer use
this feature, but those are quite rare to begin with, so this is a
reasonable trade off.
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Invoke rseq_handle_notify_resume() from tracehook_notify_resume() now
that the two function are always called back-to-back by architectures
that have rseq. The rseq helper is stubbed out for architectures that
don't support rseq, i.e. this is a nop across the board.
Note, tracehook_notify_resume() is horribly named and arguably does not
belong in tracehook.h as literally every line of code in it has nothing
to do with tracing. But, that's been true since commit a42c6ded82
("move key_repace_session_keyring() into tracehook_notify_resume()")
first usurped tracehook_notify_resume() back in 2012. Punt cleaning that
mess up to future patches.
No functional change intended.
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210901203030.1292304-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Merge more updates from Andrew Morton:
"147 patches, based on 7d2a07b769.
Subsystems affected by this patch series: mm (memory-hotplug, rmap,
ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan),
alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib,
checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig,
selftests, ipc, and scripts"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits)
scripts: check_extable: fix typo in user error message
mm/workingset: correct kernel-doc notations
ipc: replace costly bailout check in sysvipc_find_ipc()
selftests/memfd: remove unused variable
Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH
configs: remove the obsolete CONFIG_INPUT_POLLDEV
prctl: allow to setup brk for et_dyn executables
pid: cleanup the stale comment mentioning pidmap_init().
kernel/fork.c: unexport get_{mm,task}_exe_file
coredump: fix memleak in dump_vma_snapshot()
fs/coredump.c: log if a core dump is aborted due to changed file permissions
nilfs2: use refcount_dec_and_lock() to fix potential UAF
nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group
nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group
nilfs2: fix NULL pointer in nilfs_##name##_attr_release
nilfs2: fix memory leak in nilfs_sysfs_create_device_group
trap: cleanup trap_init()
init: move usermodehelper_enable() to populate_rootfs()
...
There are some empty trap_init() definitions in different ARCHs, Introduce
a new weak trap_init() function to clean them up.
Link: https://lkml.kernel.org/r/20210812123602.76356-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [arm32]
Acked-by: Vineet Gupta [arc]
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Stafford Horne <shorne@gmail.com>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <palmerdabbelt@google.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Add -s option (strict mode) to merge_config.sh to make it fail when
any symbol is redefined.
- Show a warning if a different compiler is used for building external
modules.
- Infer --target from ARCH for CC=clang to let you cross-compile the
kernel without CROSS_COMPILE.
- Make the integrated assembler default (LLVM_IAS=1) for CC=clang.
- Add <linux/stdarg.h> to the kernel source instead of borrowing
<stdarg.h> from the compiler.
- Add Nick Desaulniers as a Kbuild reviewer.
- Drop stale cc-option tests.
- Fix the combination of CONFIG_TRIM_UNUSED_KSYMS and CONFIG_LTO_CLANG
to handle symbols in inline assembly.
- Show a warning if 'FORCE' is missing for if_changed rules.
- Various cleanups
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Merge tag 'kbuild-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Add -s option (strict mode) to merge_config.sh to make it fail when
any symbol is redefined.
- Show a warning if a different compiler is used for building external
modules.
- Infer --target from ARCH for CC=clang to let you cross-compile the
kernel without CROSS_COMPILE.
- Make the integrated assembler default (LLVM_IAS=1) for CC=clang.
- Add <linux/stdarg.h> to the kernel source instead of borrowing
<stdarg.h> from the compiler.
- Add Nick Desaulniers as a Kbuild reviewer.
- Drop stale cc-option tests.
- Fix the combination of CONFIG_TRIM_UNUSED_KSYMS and CONFIG_LTO_CLANG
to handle symbols in inline assembly.
- Show a warning if 'FORCE' is missing for if_changed rules.
- Various cleanups
* tag 'kbuild-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (39 commits)
kbuild: redo fake deps at include/ksym/*.h
kbuild: clean up objtool_args slightly
modpost: get the *.mod file path more simply
checkkconfigsymbols.py: Fix the '--ignore' option
kbuild: merge vmlinux_link() between ARCH=um and other architectures
kbuild: do not remove 'linux' link in scripts/link-vmlinux.sh
kbuild: merge vmlinux_link() between the ordinary link and Clang LTO
kbuild: remove stale *.symversions
kbuild: remove unused quiet_cmd_update_lto_symversions
gen_compile_commands: extract compiler command from a series of commands
x86: remove cc-option-yn test for -mtune=
arc: replace cc-option-yn uses with cc-option
s390: replace cc-option-yn uses with cc-option
ia64: move core-y in arch/ia64/Makefile to arch/ia64/Kbuild
sparc: move the install rule to arch/sparc/Makefile
security: remove unneeded subdir-$(CONFIG_...)
kbuild: sh: remove unused install script
kbuild: Fix 'no symbols' warning when CONFIG_TRIM_UNUSD_KSYMS=y
kbuild: Switch to 'f' variants of integrated assembler flag
kbuild: Shuffle blank line to improve comment meaning
...
Merge misc updates from Andrew Morton:
"173 patches.
Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
oom-kill, migration, ksm, percpu, vmstat, and madvise)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits)
mm/madvise: add MADV_WILLNEED to process_madvise()
mm/vmstat: remove unneeded return value
mm/vmstat: simplify the array size calculation
mm/vmstat: correct some wrong comments
mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
selftests: vm: add COW time test for KSM pages
selftests: vm: add KSM merging time test
mm: KSM: fix data type
selftests: vm: add KSM merging across nodes test
selftests: vm: add KSM zero page merging test
selftests: vm: add KSM unmerge test
selftests: vm: add KSM merge test
mm/migrate: correct kernel-doc notation
mm: wire up syscall process_mrelease
mm: introduce process_mrelease system call
memblock: make memblock_find_in_range method private
mm/mempolicy.c: use in_task() in mempolicy_slab_node()
mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
mm/mempolicy: advertise new MPOL_PREFERRED_MANY
mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
...
There are a lot of uses of memblock_find_in_range() along with
memblock_reserve() from the times memblock allocation APIs did not exist.
memblock_find_in_range() is the very core of memblock allocations, so any
future changes to its internal behaviour would mandate updates of all the
users outside memblock.
Replace the calls to memblock_find_in_range() with an equivalent calls to
memblock_phys_alloc() and memblock_phys_alloc_range() and make
memblock_find_in_range() private method of memblock.
This simplifies the callers, ensures that (unlikely) errors in
memblock_reserve() are handled and improves maintainability of
memblock_find_in_range().
Link: https://lkml.kernel.org/r/20210816122622.30279-1-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Acked-by: Kirill A. Shutemov <kirill.shtuemov@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [ACPI]
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Acked-by: Nick Kossifidis <mick@ics.forth.gr> [riscv]
Tested-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'printk-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- Optionally, provide an index of possible printk messages via
<debugfs>/printk/index/. It can be used when monitoring important
kernel messages on a farm of various hosts. The monitor has to be
updated when some messages has changed or are not longer available by
a newly deployed kernel.
- Add printk.console_no_auto_verbose boot parameter. It allows to
generate crash dump even with slow consoles in a reasonable time
frame.
- Remove printk_safe buffers. The messages are always stored directly
to the main logbuffer, even in NMI or recursive context. Also it
allows to serialize syslog operations by a mutex instead of a spin
lock.
- Misc clean up and build fixes.
* tag 'printk-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk/index: Fix -Wunused-function warning
lib/nmi_backtrace: Serialize even messages about idle CPUs
printk: Add printk.console_no_auto_verbose boot parameter
printk: Remove console_silent()
lib/test_scanf: Handle n_bits == 0 in random tests
printk: syslog: close window between wait and read
printk: convert @syslog_lock to mutex
printk: remove NMI tracking
printk: remove safe buffers
printk: track/limit recursion
lib/nmi_backtrace: explicitly serialize banner and regs
printk: Move the printk() kerneldoc comment to its new home
printk/index: Fix warning about missing prototypes
MIPS/asm/printk: Fix build failure caused by printk
printk: index: Add indexing support to dev_printk
printk: Userspace format indexing support
printk: Rework parse_prefix into printk_parse_prefix
printk: Straighten out log_flags into printk_info_flags
string_helpers: Escape double quotes in escape_special
printk/console: Check consistent sequence number when handling race in console_unlock()
Li Huafei