The commit a2055abe9c ("x86/mm: Pass flush_tlb_info to
flush_tlb_others() etc") removed the unnecessary cpu parameter from
uv_flush_tlb_others() but left an unused variable.
arch/x86/mm/tlb.c: In function 'native_flush_tlb_others':
arch/x86/mm/tlb.c:688:16: warning: variable 'cpu' set but not used
[-Wunused-but-set-variable]
unsigned int cpu;
^~~
Fixes: a2055abe9c ("x86/mm: Pass flush_tlb_info to flush_tlb_others() etc")
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andyt Lutomirski <luto@kernel.org>
Cc: dave.hansen@linux.intel.com
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/20190228220155.88124-1-cai@lca.pw
When the ORC unwinder is invoked for an oops caused by IP==0,
it currently has no idea what to do because there is no debug information
for the stack frame of NULL.
But if RIP is NULL, it is very likely that the last successfully executed
instruction was an indirect CALL/JMP, and it is possible to unwind out in
the same way as for the first instruction of a normal function. Hardcode
a corresponding ORC entry.
With an artificially-added NULL call in prctl_set_seccomp(), before this
patch, the trace is:
Call Trace:
? __x64_sys_prctl+0x402/0x680
? __ia32_sys_prctl+0x6e0/0x6e0
? __do_page_fault+0x457/0x620
? do_syscall_64+0x6d/0x160
? entry_SYSCALL_64_after_hwframe+0x44/0xa9
After this patch, the trace looks like this:
Call Trace:
__x64_sys_prctl+0x402/0x680
? __ia32_sys_prctl+0x6e0/0x6e0
? __do_page_fault+0x457/0x620
do_syscall_64+0x6d/0x160
entry_SYSCALL_64_after_hwframe+0x44/0xa9
prctl_set_seccomp() still doesn't show up in the trace because for some
reason, tail call optimization is only disabled in builds that use the
frame pointer unwinder.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: syzbot <syzbot+ca95b2b7aef9e7cbd6ab@syzkaller.appspotmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: linux-kbuild@vger.kernel.org
Link: https://lkml.kernel.org/r/20190301031201.7416-2-jannh@google.com
When the frame unwinder is invoked for an oops caused by a call to NULL, it
currently skips the parent function because BP still points to the parent's
stack frame; the (nonexistent) current function only has the first half of
a stack frame, and BP doesn't point to it yet.
Add a special case for IP==0 that calculates a fake BP from SP, then uses
the real BP for the next frame.
Note that this handles first_frame specially: Return information about the
parent function as long as the saved IP is >=first_frame, even if the fake
BP points below it.
With an artificially-added NULL call in prctl_set_seccomp(), before this
patch, the trace is:
Call Trace:
? prctl_set_seccomp+0x3a/0x50
__x64_sys_prctl+0x457/0x6f0
? __ia32_sys_prctl+0x750/0x750
do_syscall_64+0x72/0x160
entry_SYSCALL_64_after_hwframe+0x44/0xa9
After this patch, the trace is:
Call Trace:
prctl_set_seccomp+0x3a/0x50
__x64_sys_prctl+0x457/0x6f0
? __ia32_sys_prctl+0x750/0x750
do_syscall_64+0x72/0x160
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: syzbot <syzbot+ca95b2b7aef9e7cbd6ab@syzkaller.appspotmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: linux-kbuild@vger.kernel.org
Link: https://lkml.kernel.org/r/20190301031201.7416-1-jannh@google.com
When compiling with -Wreturn-type, clang warns:
arch/x86/boot/compressed/kaslr.c:704:1: warning: control may reach end of
non-void function [-Wreturn-type]
This function's return statement should have been placed outside the
ifdeffed region. Move it there.
Fixes: 690eaa5320 ("x86/boot/KASLR: Limit KASLR to extract the kernel in immovable memory only")
Signed-off-by: Louis Taylor <louis@kragniz.eu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: fanc.fnst@cn.fujitsu.com
Cc: bhe@redhat.com
Cc: kirill.shutemov@linux.intel.com
Cc: jflat@chromium.org
Link: https://lkml.kernel.org/r/20190302184929.28971-1-louis@kragniz.eu
Merge misc updates from Andrew Morton:
- a few misc things
- ocfs2 updates
- most of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (159 commits)
tools/testing/selftests/proc/proc-self-syscall.c: remove duplicate include
proc: more robust bulk read test
proc: test /proc/*/maps, smaps, smaps_rollup, statm
proc: use seq_puts() everywhere
proc: read kernel cpu stat pointer once
proc: remove unused argument in proc_pid_lookup()
fs/proc/thread_self.c: code cleanup for proc_setup_thread_self()
fs/proc/self.c: code cleanup for proc_setup_self()
proc: return exit code 4 for skipped tests
mm,mremap: bail out earlier in mremap_to under map pressure
mm/sparse: fix a bad comparison
mm/memory.c: do_fault: avoid usage of stale vm_area_struct
writeback: fix inode cgroup switching comment
mm/huge_memory.c: fix "orig_pud" set but not used
mm/hotplug: fix an imbalance with DEBUG_PAGEALLOC
mm/memcontrol.c: fix bad line in comment
mm/cma.c: cma_declare_contiguous: correct err handling
mm/page_ext.c: fix an imbalance with kmemleak
mm/compaction: pass pgdat to too_many_isolated() instead of zone
mm: remove zone_lru_lock() function, access ->lru_lock directly
...
Only a few small changes this time:
- Michael S. Tsirkin cleans up linux/mman.h
- Mike Rapoport found a typo
I had originally merged another cleanup series for I/O accessors from
Hugo Lefeuvre as well, but dropped it after the discussion of the barrier
semantics and some conflicts. I expect this series to get merged for a
later release though.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Merge tag 'asm-generic-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic updates from Arnd Bergmann:
"Only a few small changes this time:
- Michael S. Tsirkin cleans up linux/mman.h
- Mike Rapoport found a typo
I had originally merged another cleanup series for I/O accessors from
Hugo Lefeuvre as well, but dropped it after the discussion of the
barrier semantics and some conflicts. I expect this series to get
merged for a later release though"
* tag 'asm-generic-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
asm-generic/page.h: fix typo in #error text requiring a real asm/page.h
arch: move common mmap flags to linux/mman.h
drm: tweak header name
x86/mpx: tweak header name
Pull x86 alternative instruction updates from Ingo Molnar:
"Small RDTSCP opimization, enabled by the newly added ALTERNATIVE_3(),
and other small improvements"
* 'x86-alternatives-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/TSC: Use RDTSCP
x86/alternatives: Add an ALTERNATIVE_3() macro
x86/alternatives: Print containing function
x86/alternatives: Add macro comments
Pull perf updates from Ingo Molnar:
"Lots of tooling updates - too many to list, here's a few highlights:
- Various subcommand updates to 'perf trace', 'perf report', 'perf
record', 'perf annotate', 'perf script', 'perf test', etc.
- CPU and NUMA topology and affinity handling improvements,
- HW tracing and HW support updates:
- Intel PT updates
- ARM CoreSight updates
- vendor HW event updates
- BPF updates
- Tons of infrastructure updates, both on the build system and the
library support side
- Documentation updates.
- ... and lots of other changes, see the changelog for details.
Kernel side updates:
- Tighten up kprobes blacklist handling, reduce the number of places
where developers can install a kprobe and hang/crash the system.
- Fix/enhance vma address filter handling.
- Various PMU driver updates, small fixes and additions.
- refcount_t conversions
- BPF updates
- error code propagation enhancements
- misc other changes"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (238 commits)
perf script python: Add Python3 support to syscall-counts-by-pid.py
perf script python: Add Python3 support to syscall-counts.py
perf script python: Add Python3 support to stat-cpi.py
perf script python: Add Python3 support to stackcollapse.py
perf script python: Add Python3 support to sctop.py
perf script python: Add Python3 support to powerpc-hcalls.py
perf script python: Add Python3 support to net_dropmonitor.py
perf script python: Add Python3 support to mem-phys-addr.py
perf script python: Add Python3 support to failed-syscalls-by-pid.py
perf script python: Add Python3 support to netdev-times.py
perf tools: Add perf_exe() helper to find perf binary
perf script: Handle missing fields with -F +..
perf data: Add perf_data__open_dir_data function
perf data: Add perf_data__(create_dir|close_dir) functions
perf data: Fail check_backup in case of error
perf data: Make check_backup work over directories
perf tools: Add rm_rf_perf_data function
perf tools: Add pattern name checking to rm_rf
perf tools: Add depth checking to rm_rf
perf data: Add global path holder
...
Pull locking updates from Ingo Molnar:
"The biggest part of this tree is the new auto-generated atomics API
wrappers by Mark Rutland.
The primary motivation was to allow instrumentation without uglifying
the primary source code.
The linecount increase comes from adding the auto-generated files to
the Git space as well:
include/asm-generic/atomic-instrumented.h | 1689 ++++++++++++++++--
include/asm-generic/atomic-long.h | 1174 ++++++++++---
include/linux/atomic-fallback.h | 2295 +++++++++++++++++++++++++
include/linux/atomic.h | 1241 +------------
I preferred this approach, so that the full call stack of the (already
complex) locking APIs is still fully visible in 'git grep'.
But if this is excessive we could certainly hide them.
There's a separate build-time mechanism to determine whether the
headers are out of date (they should never be stale if we do our job
right).
Anyway, nothing from this should be visible to regular kernel
developers.
Other changes:
- Add support for dynamic keys, which removes a source of false
positives in the workqueue code, among other things (Bart Van
Assche)
- Updates to tools/memory-model (Andrea Parri, Paul E. McKenney)
- qspinlock, wake_q and lockdep micro-optimizations (Waiman Long)
- misc other updates and enhancements"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits)
locking/lockdep: Shrink struct lock_class_key
locking/lockdep: Add module_param to enable consistency checks
lockdep/lib/tests: Test dynamic key registration
lockdep/lib/tests: Fix run_tests.sh
kernel/workqueue: Use dynamic lockdep keys for workqueues
locking/lockdep: Add support for dynamic keys
locking/lockdep: Verify whether lock objects are small enough to be used as class keys
locking/lockdep: Check data structure consistency
locking/lockdep: Reuse lock chains that have been freed
locking/lockdep: Fix a comment in add_chain_cache()
locking/lockdep: Introduce lockdep_next_lockchain() and lock_chain_count()
locking/lockdep: Reuse list entries that are no longer in use
locking/lockdep: Free lock classes that are no longer in use
locking/lockdep: Update two outdated comments
locking/lockdep: Make it easy to detect whether or not inside a selftest
locking/lockdep: Split lockdep_free_key_range() and lockdep_reset_lock()
locking/lockdep: Initialize the locks_before and locks_after lists earlier
locking/lockdep: Make zap_class() remove all matching lock order entries
locking/lockdep: Reorder struct lock_class members
locking/lockdep: Avoid that add_chain_cache() adds an invalid chain to the cache
...
Pull EFI updates from Ingo Molnar:
"The main EFI changes in this cycle were:
- Use 32-bit alignment for efi_guid_t
- Allow the SetVirtualAddressMap() call to be omitted
- Implement earlycon=efifb based on existing earlyprintk code
- Various minor fixes and code cleanups from Sai, Ard and me"
* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: Fix build error due to enum collision between efi.h and ima.h
efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation
x86: Make ARCH_USE_MEMREMAP_PROT a generic Kconfig symbol
efi/arm/arm64: Allow SetVirtualAddressMap() to be omitted
efi: Replace GPL license boilerplate with SPDX headers
efi/fdt: Apply more cleanups
efi: Use 32-bit alignment for efi_guid_t
efi/memattr: Don't bail on zero VA if it equals the region's PA
x86/efi: Mark can_free_region() as an __init function
Skylake (and later) will receive a microcode update to address a TSX
errata. This microcode will, on execution of a TSX instruction
(speculative or not) use (clobber) PMC3. This update will also provide
a new MSR to change this behaviour along with a CPUID bit to enumerate
the presence of this new MSR.
When the MSR gets set; the microcode will no longer use PMC3 but will
Force Abort every TSX transaction (upon executing COMMIT).
When TSX Force Abort (TFA) is allowed (default); the MSR gets set when
PMC3 gets scheduled and cleared when, after scheduling, PMC3 is
unused.
When TFA is not allowed; clear PMC3 from all constraints such that it
will not get used.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Skylake systems will receive a microcode update to address a TSX
errata. This microcode will (by default) clobber PMC3 when TSX
instructions are (speculatively or not) executed.
It also provides an MSR to cause all TSX transaction to abort and
preserve PMC3.
Add the CPUID enumeration and MSR definition.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The cpuc data structure allocation is different between fake and real
cpuc's; use the same code to init/free both.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The descriptions of userspace memory access functions had minor issues
with formatting that made kernel-doc unable to properly detect the
function/macro names and the return value sections:
./arch/x86/include/asm/uaccess.h:80: info: Scanning doc for
./arch/x86/include/asm/uaccess.h:139: info: Scanning doc for
./arch/x86/include/asm/uaccess.h:231: info: Scanning doc for
./arch/x86/include/asm/uaccess.h:505: info: Scanning doc for
./arch/x86/include/asm/uaccess.h:530: info: Scanning doc for
./arch/x86/lib/usercopy_32.c:58: info: Scanning doc for
./arch/x86/lib/usercopy_32.c:69: warning: No description found for return
value of 'clear_user'
./arch/x86/lib/usercopy_32.c:78: info: Scanning doc for
./arch/x86/lib/usercopy_32.c:90: warning: No description found for return
value of '__clear_user'
Fix the formatting.
Link: http://lkml.kernel.org/r/1549549644-4903-3-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Architectures like ppc64 require to do a conditional tlb flush based on
the old and new value of pte. Enable that by passing old pte value as
the arg.
Link: http://lkml.kernel.org/r/20190116085035.29729-3-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "NestMMU pte upgrade workaround for mprotect", v5.
We can upgrade pte access (R -> RW transition) via mprotect. We need to
make sure we follow the recommended pte update sequence as outlined in
commit bd5050e38a ("powerpc/mm/radix: Change pte relax sequence to
handle nest MMU hang") for such updates. This patch series does that.
This patch (of 5):
Some architectures may want to call flush_tlb_range from these helpers.
Link: http://lkml.kernel.org/r/20190116085035.29729-2-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "Replace all open encodings for NUMA_NO_NODE", v3.
All these places for replacement were found by running the following
grep patterns on the entire kernel code. Please let me know if this
might have missed some instances. This might also have replaced some
false positives. I will appreciate suggestions, inputs and review.
1. git grep "nid == -1"
2. git grep "node == -1"
3. git grep "nid = -1"
4. git grep "node = -1"
This patch (of 2):
At present there are multiple places where invalid node number is
encoded as -1. Even though implicitly understood it is always better to
have macros in there. Replace these open encodings for an invalid node
number with the global macro NUMA_NO_NODE. This helps remove NUMA
related assumptions like 'invalid node' from various places redirecting
them to a common definition.
Link: http://lkml.kernel.org/r/1545127933-10711-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> [ixgbe]
Acked-by: Jens Axboe <axboe@kernel.dk> [mtip32xx]
Acked-by: Vinod Koul <vkoul@kernel.org> [dmaengine.c]
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Acked-by: Doug Ledford <dledford@redhat.com> [drivers/infiniband]
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull year 2038 updates from Thomas Gleixner:
"Another round of changes to make the kernel ready for 2038. After lots
of preparatory work this is the first set of syscalls which are 2038
safe:
403 clock_gettime64
404 clock_settime64
405 clock_adjtime64
406 clock_getres_time64
407 clock_nanosleep_time64
408 timer_gettime64
409 timer_settime64
410 timerfd_gettime64
411 timerfd_settime64
412 utimensat_time64
413 pselect6_time64
414 ppoll_time64
416 io_pgetevents_time64
417 recvmmsg_time64
418 mq_timedsend_time64
419 mq_timedreceiv_time64
420 semtimedop_time64
421 rt_sigtimedwait_time64
422 futex_time64
423 sched_rr_get_interval_time64
The syscall numbers are identical all over the architectures"
* 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
riscv: Use latest system call ABI
checksyscalls: fix up mq_timedreceive and stat exceptions
unicore32: Fix __ARCH_WANT_STAT64 definition
asm-generic: Make time32 syscall numbers optional
asm-generic: Drop getrlimit and setrlimit syscalls from default list
32-bit userspace ABI: introduce ARCH_32BIT_OFF_T config option
compat ABI: use non-compat openat and open_by_handle_at variants
y2038: add 64-bit time_t syscalls to all 32-bit architectures
y2038: rename old time and utime syscalls
y2038: remove struct definition redirects
y2038: use time32 syscall names on 32-bit
syscalls: remove obsolete __IGNORE_ macros
y2038: syscalls: rename y2038 compat syscalls
x86/x32: use time64 versions of sigtimedwait and recvmmsg
timex: change syscalls to use struct __kernel_timex
timex: use __kernel_timex internally
sparc64: add custom adjtimex/clock_adjtime functions
time: fix sys_timer_settime prototype
time: Add struct __kernel_timex
time: make adjtime compat handling available for 32 bit
...
Pull x86/pti update from Thomas Gleixner:
"Just a single change from the anti-performance departement:
- Add a new PR_SPEC_DISABLE_NOEXEC option which allows to apply the
speculation protections on a process without inheriting the state
on exec.
This remedies a situation where a Java-launcher has speculation
protections enabled because that's the default for JVMs which
causes the launched regular harmless processes to inherit the
protection state which results in unintended performance
degradation"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation: Add PR_SPEC_DISABLE_NOEXEC
Linux supports ELF binaries for ~25 years now. a.out coredumping has
bitrotten quite significantly and would need some fixing to get it into
shape again but considering how even the toolchains cannot create a.out
executables in its default configuration, let's deprecate a.out support
and remove it a couple of releases later, instead.
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Richard Weinberger <richard@nod.at>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Jann Horn <jannh@google.com>
Cc: <linux-api@vger.kernel.org>
Cc: <linux-fsdevel@vger.kernel.org>
Cc: lkml <linux-kernel@vger.kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <x86@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We're (finally) phasing out a.out support for good. As Borislav Petkov
points out, we've supported ELF binaries for about 25 years by now, and
coredumping in particular has bitrotted over the years.
None of the tool chains even support generating a.out binaries any more,
and the plan is to deprecate a.out support entirely for the kernel. But
I want to start with just removing the core dumping code, because I can
still imagine that somebody actually might want to support a.out as a
simpler biinary format.
Particularly if you generate some random binaries on the fly, ELF is a
much more complicated format (admittedly ELF also does have a lot of
toolchain support, mitigating that complexity a lot and you really
should have moved over in the last 25 years).
So it's at least somewhat possible that somebody out there has some
workflow that still involves generating and running a.out executables.
In contrast, it's very unlikely that anybody depends on debugging any
legacy a.out core files. But regardless, I want this phase-out to be
done in two steps, so that we can resurrect a.out support (if needed)
without having to resurrect the core file dumping that is almost
certainly not needed.
Jann Horn pointed to the <asm/a.out-core.h> file that my first trivial
cut at this had missed.
And Alan Cox points out that the a.out binary loader _could_ be done in
user space if somebody wants to, but we might keep just the loader in
the kernel if somebody really wants it, since the loader isn't that big
and has no really odd special cases like the core dumping does.
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc: Jann Horn <jannh@google.com>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull crypto update from Herbert Xu:
"API:
- Add helper for simple skcipher modes.
- Add helper to register multiple templates.
- Set CRYPTO_TFM_NEED_KEY when setkey fails.
- Require neither or both of export/import in shash.
- AEAD decryption test vectors are now generated from encryption
ones.
- New option CONFIG_CRYPTO_MANAGER_EXTRA_TESTS that includes random
fuzzing.
Algorithms:
- Conversions to skcipher and helper for many templates.
- Add more test vectors for nhpoly1305 and adiantum.
Drivers:
- Add crypto4xx prng support.
- Add xcbc/cmac/ecb support in caam.
- Add AES support for Exynos5433 in s5p.
- Remove sha384/sha512 from artpec7 as hardware cannot do partial
hash"
[ There is a merge of the Freescale SoC tree in order to pull in changes
required by patches to the caam/qi2 driver. ]
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (174 commits)
crypto: s5p - add AES support for Exynos5433
dt-bindings: crypto: document Exynos5433 SlimSSS
crypto: crypto4xx - add missing of_node_put after of_device_is_available
crypto: cavium/zip - fix collision with generic cra_driver_name
crypto: af_alg - use struct_size() in sock_kfree_s()
crypto: caam - remove redundant likely/unlikely annotation
crypto: s5p - update iv after AES-CBC op end
crypto: x86/poly1305 - Clear key material from stack in SSE2 variant
crypto: caam - generate hash keys in-place
crypto: caam - fix DMA mapping xcbc key twice
crypto: caam - fix hash context DMA unmap size
hwrng: bcm2835 - fix probe as platform device
crypto: s5p-sss - Use AES_BLOCK_SIZE define instead of number
crypto: stm32 - drop pointless static qualifier in stm32_hash_remove()
crypto: chelsio - Fixed Traffic Stall
crypto: marvell - Remove set but not used variable 'ivsize'
crypto: ccp - Update driver messages to remove some confusion
crypto: adiantum - add 1536 and 4096-byte test vectors
crypto: nhpoly1305 - add a test vector with len % 16 != 0
crypto: arm/aes-ce - update IV after partial final CTR block
...
Pull networking updates from David Miller:
"Here we go, another merge window full of networking and #ebpf changes:
1) Snoop DHCPACKS in batman-adv to learn MAC/IP pairs in the DHCP
range without dealing with floods of ARP traffic, from Linus
Lüssing.
2) Throttle buffered multicast packet transmission in mt76, from
Felix Fietkau.
3) Support adaptive interrupt moderation in ice, from Brett Creeley.
4) A lot of struct_size conversions, from Gustavo A. R. Silva.
5) Add peek/push/pop commands to bpftool, as well as bash completion,
from Stanislav Fomichev.
6) Optimize sk_msg_clone(), from Vakul Garg.
7) Add SO_BINDTOIFINDEX, from David Herrmann.
8) Be more conservative with local resends due to local congestion,
from Yuchung Cheng.
9) Allow vetoing of unsupported VXLAN FDBs, from Petr Machata.
10) Add health buffer support to devlink, from Eran Ben Elisha.
11) Add TXQ scheduling API to mac80211, from Toke Høiland-Jørgensen.
12) Add statistics to basic packet scheduler filter, from Cong Wang.
13) Add GRE tunnel support for mlxsw Spectrum-2, from Nir Dotan.
14) Lots of new IP tunneling forwarding tests, also from Nir Dotan.
15) Add 3ad stats to bonding, from Nikolay Aleksandrov.
16) Lots of probing improvements for bpftool, from Quentin Monnet.
17) Various nfp drive #ebpf JIT improvements from Jakub Kicinski.
18) Allow #ebpf programs to access gso_segs from skb shared info, from
Eric Dumazet.
19) Add sock_diag support for AF_XDP sockets, from Björn Töpel.
20) Support 22260 iwlwifi devices, from Luca Coelho.
21) Use rbtree for ipv6 defragmentation, from Peter Oskolkov.
22) Add JMP32 instruction class support to #ebpf, from Jiong Wang.
23) Add spinlock support to #ebpf, from Alexei Starovoitov.
24) Support 256-bit keys and TLS 1.3 in ktls, from Dave Watson.
25) Add device infomation API to devlink, from Jakub Kicinski.
26) Add new timestamping socket options which are y2038 safe, from
Deepa Dinamani.
27) Add RX checksum offloading for various sh_eth chips, from Sergei
Shtylyov.
28) Flow offload infrastructure, from Pablo Neira Ayuso.
29) Numerous cleanups, improvements, and bug fixes to the PHY layer
and many drivers from Heiner Kallweit.
30) Lots of changes to try and make packet scheduler classifiers run
lockless as much as possible, from Vlad Buslov.
31) Support BCM957504 chip in bnxt_en driver, from Erik Burrows.
32) Add concurrency tests to tc-tests infrastructure, from Vlad
Buslov.
33) Add hwmon support to aquantia, from Heiner Kallweit.
34) Allow 64-bit values for SO_MAX_PACING_RATE, from Eric Dumazet.
And I would be remiss if I didn't thank the various major networking
subsystem maintainers for integrating much of this work before I even
saw it. Alexei Starovoitov, Daniel Borkmann, Pablo Neira Ayuso,
Johannes Berg, Kalle Valo, and many others. Thank you!"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2207 commits)
net/sched: avoid unused-label warning
net: ignore sysctl_devconf_inherit_init_net without SYSCTL
phy: mdio-mux: fix Kconfig dependencies
net: phy: use phy_modify_mmd_changed in genphy_c45_an_config_aneg
net: dsa: mv88e6xxx: add call to mv88e6xxx_ports_cmode_init to probe for new DSA framework
selftest/net: Remove duplicate header
sky2: Disable MSI on Dell Inspiron 1545 and Gateway P-79
net/mlx5e: Update tx reporter status in case channels were successfully opened
devlink: Add support for direct reporter health state update
devlink: Update reporter state to error even if recover aborted
sctp: call iov_iter_revert() after sending ABORT
team: Free BPF filter when unregistering netdev
ip6mr: Do not call __IP6_INC_STATS() from preemptible context
isdn: mISDN: Fix potential NULL pointer dereference of kzalloc
net: dsa: mv88e6xxx: support in-band signalling on SGMII ports with external PHYs
cxgb4/chtls: Prefix adapter flags with CXGB4
net-sysfs: Switch to bitmap_zalloc()
mellanox: Switch to bitmap_zalloc()
bpf: add test cases for non-pointer sanitiation logic
mlxsw: i2c: Extend initialization by querying resources data
...
The kill() syscall operates on process identifiers (pid). After a process
has exited its pid can be reused by another process. If a caller sends a
signal to a reused pid it will end up signaling the wrong process. This
issue has often surfaced and there has been a push to address this problem [1].
This patch uses file descriptors (fd) from proc/<pid> as stable handles on
struct pid. Even if a pid is recycled the handle will not change. The fd
can be used to send signals to the process it refers to.
Thus, the new syscall pidfd_send_signal() is introduced to solve this
problem. Instead of pids it operates on process fds (pidfd).
/* prototype and argument /*
long pidfd_send_signal(int pidfd, int sig, siginfo_t *info, unsigned int flags);
/* syscall number 424 */
The syscall number was chosen to be 424 to align with Arnd's rework in his
y2038 to minimize merge conflicts (cf. [25]).
In addition to the pidfd and signal argument it takes an additional
siginfo_t and flags argument. If the siginfo_t argument is NULL then
pidfd_send_signal() is equivalent to kill(<positive-pid>, <signal>). If it
is not NULL pidfd_send_signal() is equivalent to rt_sigqueueinfo().
The flags argument is added to allow for future extensions of this syscall.
It currently needs to be passed as 0. Failing to do so will cause EINVAL.
/* pidfd_send_signal() replaces multiple pid-based syscalls */
The pidfd_send_signal() syscall currently takes on the job of
rt_sigqueueinfo(2) and parts of the functionality of kill(2), Namely, when a
positive pid is passed to kill(2). It will however be possible to also
replace tgkill(2) and rt_tgsigqueueinfo(2) if this syscall is extended.
/* sending signals to threads (tid) and process groups (pgid) */
Specifically, the pidfd_send_signal() syscall does currently not operate on
process groups or threads. This is left for future extensions.
In order to extend the syscall to allow sending signal to threads and
process groups appropriately named flags (e.g. PIDFD_TYPE_PGID, and
PIDFD_TYPE_TID) should be added. This implies that the flags argument will
determine what is signaled and not the file descriptor itself. Put in other
words, grouping in this api is a property of the flags argument not a
property of the file descriptor (cf. [13]). Clarification for this has been
requested by Eric (cf. [19]).
When appropriate extensions through the flags argument are added then
pidfd_send_signal() can additionally replace the part of kill(2) which
operates on process groups as well as the tgkill(2) and
rt_tgsigqueueinfo(2) syscalls.
How such an extension could be implemented has been very roughly sketched
in [14], [15], and [16]. However, this should not be taken as a commitment
to a particular implementation. There might be better ways to do it.
Right now this is intentionally left out to keep this patchset as simple as
possible (cf. [4]).
/* naming */
The syscall had various names throughout iterations of this patchset:
- procfd_signal()
- procfd_send_signal()
- taskfd_send_signal()
In the last round of reviews it was pointed out that given that if the
flags argument decides the scope of the signal instead of different types
of fds it might make sense to either settle for "procfd_" or "pidfd_" as
prefix. The community was willing to accept either (cf. [17] and [18]).
Given that one developer expressed strong preference for the "pidfd_"
prefix (cf. [13]) and with other developers less opinionated about the name
we should settle for "pidfd_" to avoid further bikeshedding.
The "_send_signal" suffix was chosen to reflect the fact that the syscall
takes on the job of multiple syscalls. It is therefore intentional that the
name is not reminiscent of neither kill(2) nor rt_sigqueueinfo(2). Not the
fomer because it might imply that pidfd_send_signal() is a replacement for
kill(2), and not the latter because it is a hassle to remember the correct
spelling - especially for non-native speakers - and because it is not
descriptive enough of what the syscall actually does. The name
"pidfd_send_signal" makes it very clear that its job is to send signals.
/* zombies */
Zombies can be signaled just as any other process. No special error will be
reported since a zombie state is an unreliable state (cf. [3]). However,
this can be added as an extension through the @flags argument if the need
ever arises.
/* cross-namespace signals */
The patch currently enforces that the signaler and signalee either are in
the same pid namespace or that the signaler's pid namespace is an ancestor
of the signalee's pid namespace. This is done for the sake of simplicity
and because it is unclear to what values certain members of struct
siginfo_t would need to be set to (cf. [5], [6]).
/* compat syscalls */
It became clear that we would like to avoid adding compat syscalls
(cf. [7]). The compat syscall handling is now done in kernel/signal.c
itself by adding __copy_siginfo_from_user_generic() which lets us avoid
compat syscalls (cf. [8]). It should be noted that the addition of
__copy_siginfo_from_user_any() is caused by a bug in the original
implementation of rt_sigqueueinfo(2) (cf. 12).
With upcoming rework for syscall handling things might improve
significantly (cf. [11]) and __copy_siginfo_from_user_any() will not gain
any additional callers.
/* testing */
This patch was tested on x64 and x86.
/* userspace usage */
An asciinema recording for the basic functionality can be found under [9].
With this patch a process can be killed via:
#define _GNU_SOURCE
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>
static inline int do_pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
unsigned int flags)
{
#ifdef __NR_pidfd_send_signal
return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
#else
return -ENOSYS;
#endif
}
int main(int argc, char *argv[])
{
int fd, ret, saved_errno, sig;
if (argc < 3)
exit(EXIT_FAILURE);
fd = open(argv[1], O_DIRECTORY | O_CLOEXEC);
if (fd < 0) {
printf("%s - Failed to open \"%s\"\n", strerror(errno), argv[1]);
exit(EXIT_FAILURE);
}
sig = atoi(argv[2]);
printf("Sending signal %d to process %s\n", sig, argv[1]);
ret = do_pidfd_send_signal(fd, sig, NULL, 0);
saved_errno = errno;
close(fd);
errno = saved_errno;
if (ret < 0) {
printf("%s - Failed to send signal %d to process %s\n",
strerror(errno), sig, argv[1]);
exit(EXIT_FAILURE);
}
exit(EXIT_SUCCESS);
}
/* Q&A
* Given that it seems the same questions get asked again by people who are
* late to the party it makes sense to add a Q&A section to the commit
* message so it's hopefully easier to avoid duplicate threads.
*
* For the sake of progress please consider these arguments settled unless
* there is a new point that desperately needs to be addressed. Please make
* sure to check the links to the threads in this commit message whether
* this has not already been covered.
*/
Q-01: (Florian Weimer [20], Andrew Morton [21])
What happens when the target process has exited?
A-01: Sending the signal will fail with ESRCH (cf. [22]).
Q-02: (Andrew Morton [21])
Is the task_struct pinned by the fd?
A-02: No. A reference to struct pid is kept. struct pid - as far as I
understand - was created exactly for the reason to not require to
pin struct task_struct (cf. [22]).
Q-03: (Andrew Morton [21])
Does the entire procfs directory remain visible? Just one entry
within it?
A-03: The same thing that happens right now when you hold a file descriptor
to /proc/<pid> open (cf. [22]).
Q-04: (Andrew Morton [21])
Does the pid remain reserved?
A-04: No. This patchset guarantees a stable handle not that pids are not
recycled (cf. [22]).
Q-05: (Andrew Morton [21])
Do attempts to signal that fd return errors?
A-05: See {Q,A}-01.
Q-06: (Andrew Morton [22])
Is there a cleaner way of obtaining the fd? Another syscall perhaps.
A-06: Userspace can already trivially retrieve file descriptors from procfs
so this is something that we will need to support anyway. Hence,
there's no immediate need to add another syscalls just to make
pidfd_send_signal() not dependent on the presence of procfs. However,
adding a syscalls to get such file descriptors is planned for a
future patchset (cf. [22]).
Q-07: (Andrew Morton [21] and others)
This fd-for-a-process sounds like a handy thing and people may well
think up other uses for it in the future, probably unrelated to
signals. Are the code and the interface designed to permit such
future applications?
A-07: Yes (cf. [22]).
Q-08: (Andrew Morton [21] and others)
Now I think about it, why a new syscall? This thing is looking
rather like an ioctl?
A-08: This has been extensively discussed. It was agreed that a syscall is
preferred for a variety or reasons. Here are just a few taken from
prior threads. Syscalls are safer than ioctl()s especially when
signaling to fds. Processes are a core kernel concept so a syscall
seems more appropriate. The layout of the syscall with its four
arguments would require the addition of a custom struct for the
ioctl() thereby causing at least the same amount or even more
complexity for userspace than a simple syscall. The new syscall will
replace multiple other pid-based syscalls (see description above).
The file-descriptors-for-processes concept introduced with this
syscall will be extended with other syscalls in the future. See also
[22], [23] and various other threads already linked in here.
Q-09: (Florian Weimer [24])
What happens if you use the new interface with an O_PATH descriptor?
A-09:
pidfds opened as O_PATH fds cannot be used to send signals to a
process (cf. [2]). Signaling processes through pidfds is the
equivalent of writing to a file. Thus, this is not an operation that
operates "purely at the file descriptor level" as required by the
open(2) manpage. See also [4].
/* References */
[1]: https://lore.kernel.org/lkml/20181029221037.87724-1-dancol@google.com/
[2]: https://lore.kernel.org/lkml/874lbtjvtd.fsf@oldenburg2.str.redhat.com/
[3]: https://lore.kernel.org/lkml/20181204132604.aspfupwjgjx6fhva@brauner.io/
[4]: https://lore.kernel.org/lkml/20181203180224.fkvw4kajtbvru2ku@brauner.io/
[5]: https://lore.kernel.org/lkml/20181121213946.GA10795@mail.hallyn.com/
[6]: https://lore.kernel.org/lkml/20181120103111.etlqp7zop34v6nv4@brauner.io/
[7]: https://lore.kernel.org/lkml/36323361-90BD-41AF-AB5B-EE0D7BA02C21@amacapital.net/
[8]: https://lore.kernel.org/lkml/87tvjxp8pc.fsf@xmission.com/
[9]: https://asciinema.org/a/IQjuCHew6bnq1cr78yuMv16cy
[11]: https://lore.kernel.org/lkml/F53D6D38-3521-4C20-9034-5AF447DF62FF@amacapital.net/
[12]: https://lore.kernel.org/lkml/87zhtjn8ck.fsf@xmission.com/
[13]: https://lore.kernel.org/lkml/871s6u9z6u.fsf@xmission.com/
[14]: https://lore.kernel.org/lkml/20181206231742.xxi4ghn24z4h2qki@brauner.io/
[15]: https://lore.kernel.org/lkml/20181207003124.GA11160@mail.hallyn.com/
[16]: https://lore.kernel.org/lkml/20181207015423.4miorx43l3qhppfz@brauner.io/
[17]: https://lore.kernel.org/lkml/CAGXu5jL8PciZAXvOvCeCU3wKUEB_dU-O3q0tDw4uB_ojMvDEew@mail.gmail.com/
[18]: https://lore.kernel.org/lkml/20181206222746.GB9224@mail.hallyn.com/
[19]: https://lore.kernel.org/lkml/20181208054059.19813-1-christian@brauner.io/
[20]: https://lore.kernel.org/lkml/8736rebl9s.fsf@oldenburg.str.redhat.com/
[21]: https://lore.kernel.org/lkml/20181228152012.dbf0508c2508138efc5f2bbe@linux-foundation.org/
[22]: https://lore.kernel.org/lkml/20181228233725.722tdfgijxcssg76@brauner.io/
[23]: https://lwn.net/Articles/773459/
[24]: https://lore.kernel.org/lkml/8736rebl9s.fsf@oldenburg.str.redhat.com/
[25]: https://lore.kernel.org/lkml/CAK8P3a0ej9NcJM8wXNPbcGUyOUZYX+VLoDFdbenW3s3114oQZw@mail.gmail.com/
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Jann Horn <jannh@google.com>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Tycho Andersen <tycho@tycho.ws>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Serge Hallyn <serge@hallyn.com>
Acked-by: Aleksa Sarai <cyphar@cyphar.com>
Arnd reported the following compiler warning:
arch/x86/kernel/ftrace.c:669:23: error: 'ftrace_jmp_replace' defined but not used [-Werror=unused-function]
The ftrace_jmp_replace() function now only has a single user and should be
simply moved by that user. But looking at the code, it shows that
ftrace_jmp_replace() is similar to ftrace_call_replace() except that instead
of using the opcode of 0xe8 it uses 0xe9. It makes more sense to consolidate
that function into one implementation that both ftrace_jmp_replace() and
ftrace_call_replace() use by passing in the op code separate.
The structure in ftrace_code_union is also modified to replace the "e8"
field with the more appropriate name "op".
Cc: stable@vger.kernel.org
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: http://lkml.kernel.org/r/20190304200748.1418790-1-arnd@arndb.de
Fixes: d2a68c4eff ("x86/ftrace: Do not call function graph from dynamic trampolines")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The legacy hypercall handlers were originally added with
a comment explaining that "copying the argument structures in
HYPERVISOR_event_channel_op() and HYPERVISOR_physdev_op() into the local
variable is sufficiently safe" and only made sure to not write
past the end of the argument structure, the checks in linux/string.h
disagree with that, when link-time optimizations are used:
In function 'memcpy',
inlined from 'pirq_query_unmask' at drivers/xen/fallback.c:53:2,
inlined from '__startup_pirq' at drivers/xen/events/events_base.c:529:2,
inlined from 'restore_pirqs' at drivers/xen/events/events_base.c:1439:3,
inlined from 'xen_irq_resume' at drivers/xen/events/events_base.c:1581:2:
include/linux/string.h:350:3: error: call to '__read_overflow2' declared with attribute error: detected read beyond size of object passed as 2nd parameter
__read_overflow2();
^
Further research turned out that only Xen 3.0.2 or earlier required the
fallback at all, while all versions in use today don't need it.
As far as I can tell, it is not even possible to run a mainline kernel
on those old Xen releases, at the time when they were in use, only
a patched kernel was supported anyway.
Fixes: cf47a83fb0 ("xen/hypercall: fix hypercall fallback code for very old hypervisors")
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Juergen Gross <jgross@suse.com>
The bulk of the standout changes in this release are cleanups, with the
core work being a combination of factoring out common code into helpers
and the completion of the conversion of the core to use GPIO
descriptors.
- Addition of helper functions for current limits and conversion of
drivers to use them by Axel Lin.
- Lots and lots of cleanups from Axel Lin.
- Conversion of the core to use GPIO descriptors rather than numbers by
Linus Walleij.
- New drivers for Maxim MAX77650 and ROHM BD70528.
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Merge tag 'regulator-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator updates from Mark Brown:
"The bulk of the standout changes in this release are cleanups, with
the core work being a combination of factoring out common code into
helpers and the completion of the conversion of the core to use GPIO
descriptors.
Summary:
- Addition of helper functions for current limits and conversion of
drivers to use them by Axel Lin.
- Lots and lots of cleanups from Axel Lin.
- Conversion of the core to use GPIO descriptors rather than numbers
by Linus Walleij.
- New drivers for Maxim MAX77650 and ROHM BD70528"
* tag 'regulator-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (131 commits)
regulator: mc13xxx: Constify regulator_ops variables
regulator: palmas: Constify palmas_smps_ramp_delay array
regulator: wm831x-dcdc: Convert to use regulator_set/get_current_limit_regmap
regulator: pv88090: Convert to use regulator_set/get_current_limit_regmap
regulator: pv88080: Convert to use regulator_set/get_current_limit_regmap
regulator: pv88060: Convert to use regulator_set/get_current_limit_regmap
regulator: max77650: Convert to use regulator_set/get_current_limit_regmap
regulator: lp873x: Convert to use regulator_set/get_current_limit_regmap
regulator: lp872x: Convert to use regulator_set/get_current_limit_regmap
regulator: da9210: Convert to use regulator_set/get_current_limit_regmap
regulator: da9055: Convert to use regulator_set/get_current_limit_regmap
regulator: core: Add set/get_current_limit helpers for regmap users
regulator: Fix comment for csel_reg and csel_mask
regulator: stm32-vrefbuf: add power management support
regulator: 88pm8607: Remove unused fields from struct pm8607_regulator_info
regulator: 88pm8607: Simplify pm8607_list_voltage implementation
regulator: cpcap: Constify omap4_regulators and xoom_regulators
regulator: cpcap: Remove unused vsel_shift from struct cpcap_regulator
dt-bindings: regulator: tps65218: rectify units of LS3
dt-bindings: regulator: add LS2 load switch documentation
...
Every in-kernel use of this function defined it to KERNEL_DS (either as
an actual define, or as an inline function). It's an entirely
historical artifact, and long long long ago used to actually read the
segment selector valueof '%ds' on x86.
Which in the kernel is always KERNEL_DS.
Inspired by a patch from Jann Horn that just did this for a very small
subset of users (the ones in fs/), along with Al who suggested a script.
I then just took it to the logical extreme and removed all the remaining
gunk.
Roughly scripted with
git grep -l '(get_ds())' -- :^tools/ | xargs sed -i 's/(get_ds())/(KERNEL_DS)/'
git grep -lw 'get_ds' -- :^tools/ | xargs sed -i '/^#define get_ds()/d'
plus manual fixups to remove a few unusual usage patterns, the couple of
inline function cases and to fix up a comment that had become stale.
The 'get_ds()' function remains in an x86 kvm selftest, since in user
space it actually does something relevant.
Inspired-by: Jann Horn <jannh@google.com>
Inspired-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds a warning (once) for any kernel dereference that has a user
exception handler, but accesses a non-canonical address. It basically
is a simpler - and more limited - version of commit 9da3f2b740
("x86/fault: BUG() when uaccess helpers fault on kernel addresses") that
got reverted.
Note that unlike that original commit, this only causes a warning,
because there are real situations where we currently can do this
(notably speculative argument fetching for uprobes etc). Also, unlike
that original commit, this _only_ triggers for #GP accesses, so the
cases of valid kernel pointers that cross into a non-mapped page aren't
affected.
The intent of this is two-fold:
- the uprobe/tracing accesses really do need to be more careful. In
particular, from a portability standpoint it's just wrong to think
that "a pointer is a pointer", and use the same logic for any random
pointer value you find on the stack. It may _work_ on x86-64, but it
doesn't necessarily work on other architectures (where the same
pointer value can be either a kernel pointer _or_ a user pointer, and
you really need to be much more careful in how you try to access it)
The warning can hopefully end up being a reminder that just any
random pointer access won't do.
- Kees in particular wanted a way to actually report invalid uses of
wild pointers to user space accessors, instead of just silently
failing them. Automated fuzzers want a way to get reports if the
kernel ever uses invalid values that the fuzzer fed it.
The non-canonical address range is a fair chunk of the address space,
and with this you can teach syzkaller to feed in invalid pointer
values and find cases where we do not properly validate user
addresses (possibly due to bad uses of "set_fs()").
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Jann Horn <jannh@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 fixes from Thomas Gleixner:
"Two last minute fixes:
- Prevent value evaluation via functions happening in the user access
enabled region of __put_user() (put another way: make sure to
evaluate the value to be stored in user space _before_ enabling
user space accesses)
- Correct the definition of a Hyper-V hypercall constant"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/hyper-v: Fix definition of HV_MAX_FLUSH_REP_COUNT
x86/uaccess: Don't leak the AC flag into __put_user() value evaluation
Remove the duplicate implementation of cpumask_to_vpset() and use the
shared implementation. Export hv_max_vp_index, which is required by
cpumask_to_vpset().
Signed-off-by: Maya Nakamura <m.maya.nakamura@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
If we have fixed user buffers, we can map them into the kernel when we
setup the io_uring. That avoids the need to do get_user_pages() for
each and every IO.
To utilize this feature, the application must call io_uring_register()
after having setup an io_uring instance, passing in
IORING_REGISTER_BUFFERS as the opcode. The argument must be a pointer to
an iovec array, and the nr_args should contain how many iovecs the
application wishes to map.
If successful, these buffers are now mapped into the kernel, eligible
for IO. To use these fixed buffers, the application must use the
IORING_OP_READ_FIXED and IORING_OP_WRITE_FIXED opcodes, and then
set sqe->index to the desired buffer index. sqe->addr..sqe->addr+seq->len
must point to somewhere inside the indexed buffer.
The application may register buffers throughout the lifetime of the
io_uring instance. It can call io_uring_register() with
IORING_UNREGISTER_BUFFERS as the opcode to unregister the current set of
buffers, and then register a new set. The application need not
unregister buffers explicitly before shutting down the io_uring
instance.
It's perfectly valid to setup a larger buffer, and then sometimes only
use parts of it for an IO. As long as the range is within the originally
mapped region, it will work just fine.
For now, buffers must not be file backed. If file backed buffers are
passed in, the registration will fail with -1/EOPNOTSUPP. This
restriction may be relaxed in the future.
RLIMIT_MEMLOCK is used to check how much memory we can pin. A somewhat
arbitrary 1G per buffer size is also imposed.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The submission queue (SQ) and completion queue (CQ) rings are shared
between the application and the kernel. This eliminates the need to
copy data back and forth to submit and complete IO.
IO submissions use the io_uring_sqe data structure, and completions
are generated in the form of io_uring_cqe data structures. The SQ
ring is an index into the io_uring_sqe array, which makes it possible
to submit a batch of IOs without them being contiguous in the ring.
The CQ ring is always contiguous, as completion events are inherently
unordered, and hence any io_uring_cqe entry can point back to an
arbitrary submission.
Two new system calls are added for this:
io_uring_setup(entries, params)
Sets up an io_uring instance for doing async IO. On success,
returns a file descriptor that the application can mmap to
gain access to the SQ ring, CQ ring, and io_uring_sqes.
io_uring_enter(fd, to_submit, min_complete, flags, sigset, sigsetsize)
Initiates IO against the rings mapped to this fd, or waits for
them to complete, or both. The behavior is controlled by the
parameters passed in. If 'to_submit' is non-zero, then we'll
try and submit new IO. If IORING_ENTER_GETEVENTS is set, the
kernel will wait for 'min_complete' events, if they aren't
already available. It's valid to set IORING_ENTER_GETEVENTS
and 'min_complete' == 0 at the same time, this allows the
kernel to return already completed events without waiting
for them. This is useful only for polling, as for IRQ
driven IO, the application can just check the CQ ring
without entering the kernel.
With this setup, it's possible to do async IO with a single system
call. Future developments will enable polled IO with this interface,
and polled submission as well. The latter will enable an application
to do IO without doing ANY system calls at all.
For IRQ driven IO, an application only needs to enter the kernel for
completions if it wants to wait for them to occur.
Each io_uring is backed by a workqueue, to support buffered async IO
as well. We will only punt to an async context if the command would
need to wait for IO on the device side. Any data that can be accessed
directly in the page cache is done inline. This avoids the slowness
issue of usual threadpools, since cached data is accessed as quickly
as a sync interface.
Sample application: http://git.kernel.dk/cgit/fio/plain/t/io_uring.c
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
EFI systems do not necessarily provide a legacy ROM. If the ROM is missing
the memory is not mapped at all.
Trying to dereference values in the legacy ROM area leads to a crash on
Macbook Pro.
Only look for values in the legacy ROM area for non-EFI system.
Fixes: 3548e131ec ("x86/boot/compressed/64: Find a place for 32-bit trampoline")
Reported-by: Pitam Mitra <pitamm@gmail.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Bockjoo Kim <bockjoo@phys.ufl.edu>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190219075224.35058-1-kirill.shutemov@linux.intel.com
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202351
From networking side, there are numerous attempts to get rid of indirect
calls in fast-path wherever feasible in order to avoid the cost of
retpolines, for example, just to name a few:
* 283c16a2df ("indirect call wrappers: helpers to speed-up indirect calls of builtin")
* aaa5d90b39 ("net: use indirect call wrappers at GRO network layer")
* 028e0a4766 ("net: use indirect call wrappers at GRO transport layer")
* 356da6d0cd ("dma-mapping: bypass indirect calls for dma-direct")
* 09772d92cd ("bpf: avoid retpoline for lookup/update/delete calls on maps")
* 10870dd89e ("netfilter: nf_tables: add direct calls for all builtin expressions")
[...]
Recent work on XDP from Björn and Magnus additionally found that manually
transforming the XDP return code switch statement with more than 5 cases
into if-else combination would result in a considerable speedup in XDP
layer due to avoidance of indirect calls in CONFIG_RETPOLINE enabled
builds. On i40e driver with XDP prog attached, a 20-26% speedup has been
observed [0]. Aside from XDP, there are many other places later in the
networking stack's critical path with similar switch-case
processing. Rather than fixing every XDP-enabled driver and locations in
stack by hand, it would be good to instead raise the limit where gcc would
emit expensive indirect calls from the switch under retpolines and stick
with the default as-is in case of !retpoline configured kernels. This would
also have the advantage that for archs where this is not necessary, we let
compiler select the underlying target optimization for these constructs and
avoid potential slow-downs by if-else hand-rewrite.
In case of gcc, this setting is controlled by case-values-threshold which
has an architecture global default that selects 4 or 5 (latter if target
does not have a case insn that compares the bounds) where some arch back
ends like arm64 or s390 override it with their own target hooks, for
example, in gcc commit db7a90aa0de5 ("S/390: Disable prediction of indirect
branches") the threshold pretty much disables jump tables by limit of 20
under retpoline builds. Comparing gcc's and clang's default code
generation on x86-64 under O2 level with retpoline build results in the
following outcome for 5 switch cases:
* gcc with -mindirect-branch=thunk-inline -mindirect-branch-register:
# gdb -batch -ex 'disassemble dispatch' ./c-switch
Dump of assembler code for function dispatch:
0x0000000000400be0 <+0>: cmp $0x4,%edi
0x0000000000400be3 <+3>: ja 0x400c35 <dispatch+85>
0x0000000000400be5 <+5>: lea 0x915f8(%rip),%rdx # 0x4921e4
0x0000000000400bec <+12>: mov %edi,%edi
0x0000000000400bee <+14>: movslq (%rdx,%rdi,4),%rax
0x0000000000400bf2 <+18>: add %rdx,%rax
0x0000000000400bf5 <+21>: callq 0x400c01 <dispatch+33>
0x0000000000400bfa <+26>: pause
0x0000000000400bfc <+28>: lfence
0x0000000000400bff <+31>: jmp 0x400bfa <dispatch+26>
0x0000000000400c01 <+33>: mov %rax,(%rsp)
0x0000000000400c05 <+37>: retq
0x0000000000400c06 <+38>: nopw %cs:0x0(%rax,%rax,1)
0x0000000000400c10 <+48>: jmpq 0x400c90 <fn_3>
0x0000000000400c15 <+53>: nopl (%rax)
0x0000000000400c18 <+56>: jmpq 0x400c70 <fn_2>
0x0000000000400c1d <+61>: nopl (%rax)
0x0000000000400c20 <+64>: jmpq 0x400c50 <fn_1>
0x0000000000400c25 <+69>: nopl (%rax)
0x0000000000400c28 <+72>: jmpq 0x400c40 <fn_0>
0x0000000000400c2d <+77>: nopl (%rax)
0x0000000000400c30 <+80>: jmpq 0x400cb0 <fn_4>
0x0000000000400c35 <+85>: push %rax
0x0000000000400c36 <+86>: callq 0x40dd80 <abort>
End of assembler dump.
* clang with -mretpoline emitting search tree:
# gdb -batch -ex 'disassemble dispatch' ./c-switch
Dump of assembler code for function dispatch:
0x0000000000400b30 <+0>: cmp $0x1,%edi
0x0000000000400b33 <+3>: jle 0x400b44 <dispatch+20>
0x0000000000400b35 <+5>: cmp $0x2,%edi
0x0000000000400b38 <+8>: je 0x400b4d <dispatch+29>
0x0000000000400b3a <+10>: cmp $0x3,%edi
0x0000000000400b3d <+13>: jne 0x400b52 <dispatch+34>
0x0000000000400b3f <+15>: jmpq 0x400c50 <fn_3>
0x0000000000400b44 <+20>: test %edi,%edi
0x0000000000400b46 <+22>: jne 0x400b5c <dispatch+44>
0x0000000000400b48 <+24>: jmpq 0x400c20 <fn_0>
0x0000000000400b4d <+29>: jmpq 0x400c40 <fn_2>
0x0000000000400b52 <+34>: cmp $0x4,%edi
0x0000000000400b55 <+37>: jne 0x400b66 <dispatch+54>
0x0000000000400b57 <+39>: jmpq 0x400c60 <fn_4>
0x0000000000400b5c <+44>: cmp $0x1,%edi
0x0000000000400b5f <+47>: jne 0x400b66 <dispatch+54>
0x0000000000400b61 <+49>: jmpq 0x400c30 <fn_1>
0x0000000000400b66 <+54>: push %rax
0x0000000000400b67 <+55>: callq 0x40dd20 <abort>
End of assembler dump.
For sake of comparison, clang without -mretpoline:
# gdb -batch -ex 'disassemble dispatch' ./c-switch
Dump of assembler code for function dispatch:
0x0000000000400b30 <+0>: cmp $0x4,%edi
0x0000000000400b33 <+3>: ja 0x400b57 <dispatch+39>
0x0000000000400b35 <+5>: mov %edi,%eax
0x0000000000400b37 <+7>: jmpq *0x492148(,%rax,8)
0x0000000000400b3e <+14>: jmpq 0x400bf0 <fn_0>
0x0000000000400b43 <+19>: jmpq 0x400c30 <fn_4>
0x0000000000400b48 <+24>: jmpq 0x400c10 <fn_2>
0x0000000000400b4d <+29>: jmpq 0x400c20 <fn_3>
0x0000000000400b52 <+34>: jmpq 0x400c00 <fn_1>
0x0000000000400b57 <+39>: push %rax
0x0000000000400b58 <+40>: callq 0x40dcf0 <abort>
End of assembler dump.
Raising the cases to a high number (e.g. 100) will still result in similar
code generation pattern with clang and gcc as above, in other words clang
generally turns off jump table emission by having an extra expansion pass
under retpoline build to turn indirectbr instructions from their IR into
switch instructions as a built-in -mno-jump-table lowering of a switch (in
this case, even if IR input already contained an indirect branch).
For gcc, adding --param=case-values-threshold=20 as in similar fashion as
s390 in order to raise the limit for x86 retpoline enabled builds results
in a small vmlinux size increase of only 0.13% (before=18,027,528
after=18,051,192). For clang this option is ignored due to i) not being
needed as mentioned and ii) not having above cmdline
parameter. Non-retpoline-enabled builds with gcc continue to use the
default case-values-threshold setting, so nothing changes here.
[0] https://lore.kernel.org/netdev/20190129095754.9390-1-bjorn.topel@gmail.com/
and "The Path to DPDK Speeds for AF_XDP", LPC 2018, networking track:
- http://vger.kernel.org/lpc_net2018_talks/lpc18_pres_af_xdp_perf-v3.pdf
- http://vger.kernel.org/lpc_net2018_talks/lpc18_paper_af_xdp_perf-v2.pdf
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: netdev@vger.kernel.org
Cc: David S. Miller <davem@davemloft.net>
Cc: Magnus Karlsson <magnus.karlsson@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/20190221221941.29358-1-daniel@iogearbox.net
Hyper-V doesn't provide irq remapping for IO-APIC. To enable x2apic,
set x2apic destination mode to physcial mode when x2apic is available
and Hyper-V IOMMU driver makes sure cpus assigned with IO-APIC irqs have
8-bit APIC id.
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Make kernfs support superblock creation/mount/remount with fs_context.
This requires that sysfs, cgroup and intel_rdt, which are built on kernfs,
be made to support fs_context also.
Notes:
(1) A kernfs_fs_context struct is created to wrap fs_context and the
kernfs mount parameters are moved in here (or are in fs_context).
(2) kernfs_mount{,_ns}() are made into kernfs_get_tree(). The extra
namespace tag parameter is passed in the context if desired
(3) kernfs_free_fs_context() is provided as a destructor for the
kernfs_fs_context struct, but for the moment it does nothing except
get called in the right places.
(4) sysfs doesn't wrap kernfs_fs_context since it has no parameters to
pass, but possibly this should be done anyway in case someone wants to
add a parameter in future.
(5) A cgroup_fs_context struct is created to wrap kernfs_fs_context and
the cgroup v1 and v2 mount parameters are all moved there.
(6) cgroup1 parameter parsing error messages are now handled by invalf(),
which allows userspace to collect them directly.
(7) cgroup1 parameter cleanup is now done in the context destructor rather
than in the mount/get_tree and remount functions.
Weirdies:
(*) cgroup_do_get_tree() calls cset_cgroup_from_root() with locks held,
but then uses the resulting pointer after dropping the locks. I'm
told this is okay and needs commenting.
(*) The cgroup refcount web. This really needs documenting.
(*) cgroup2 only has one root?
Add a suggestion from Thomas Gleixner in which the RDT enablement code is
placed into its own function.
[folded a leak fix from Andrey Vagin]
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cc: Tejun Heo <tj@kernel.org>
cc: Li Zefan <lizefan@huawei.com>
cc: Johannes Weiner <hannes@cmpxchg.org>
cc: cgroups@vger.kernel.org
cc: fenghua.yu@intel.com
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
perf annotate:
Wei Li:
- Fix getting source line failure
perf script:
Andi Kleen:
- Handle missing fields with -F +...
perf data:
Jiri Olsa:
- Prep work to support per-cpu files in a directory.
Intel PT:
Adrian Hunter:
- Improve thread_stack__no_call_return()
- Hide x86 retpolines in thread stacks.
- exported SQL viewer refactorings, new 'top calls' report..
Alexander Shishkin:
- Copy parent's address filter offsets on clone
- Fix address filters for vmas with non-zero offset. Applies to
ARM's CoreSight as well.
python scripts:
Tony Jones:
- Python3 support for several 'perf script' python scripts.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-5.1-20190225' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
perf annotate:
Wei Li:
- Fix getting source line failure
perf script:
Andi Kleen:
- Handle missing fields with -F +...
perf data:
Jiri Olsa:
- Prep work to support per-cpu files in a directory.
Intel PT:
Adrian Hunter:
- Improve thread_stack__no_call_return()
- Hide x86 retpolines in thread stacks.
- exported SQL viewer refactorings, new 'top calls' report..
Alexander Shishkin:
- Copy parent's address filter offsets on clone
- Fix address filters for vmas with non-zero offset. Applies to
ARM's CoreSight as well.
python scripts:
Tony Jones:
- Python3 support for several 'perf script' python scripts.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
1-block SSE2 variant of poly1305 stores variables s1..s4 containing key
material on the stack. This commit adds missing zeroing of the stack
memory. Benchmarks show negligible performance hit (tested on i7-3770).
Signed-off-by: Tommi Hirvola <tommi@hirvola.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This is a follow-up to the y2038 syscall patches already merged in the tip
tree. As the final 32-bit RISC-V syscall ABI is still being decided on,
this is the last chance to make a few corrections to leave out interfaces
based on 32-bit time_t along with the old off_t and rlimit types.
The series achieves this in a few steps:
- A couple of bug fixes for minor regressions I introduced
in the original series
- A couple of older patches from Yury Norov that I had never
merged in the past, these fix up the openat/open_by_handle_at and
getrlimit/setrlimit syscalls to disallow the old versions of off_t
and rlimit.
- Hiding the deprecated system calls behind an #ifdef in
include/uapi/asm-generic/unistd.h
- Change arch/riscv to drop all these ABIs.
Originally, the plan was to also leave these out on C-Sky, but that now
has a glibc port that uses the older interfaces, so we need to leave
them in place.
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Merge tag 'y2038-syscall-abi' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground into timers/2038
Pull additional syscall ABI cleanup for y2038 from Arnd Bergmann:
This is a follow-up to the y2038 syscall patches already merged in the tip
tree. As the final 32-bit RISC-V syscall ABI is still being decided on,
this is the last chance to make a few corrections to leave out interfaces
based on 32-bit time_t along with the old off_t and rlimit types.
The series achieves this in a few steps:
- A couple of bug fixes for minor regressions I introduced
in the original series
- A couple of older patches from Yury Norov that I had never
merged in the past, these fix up the openat/open_by_handle_at and
getrlimit/setrlimit syscalls to disallow the old versions of off_t
and rlimit.
- Hiding the deprecated system calls behind an #ifdef in
include/uapi/asm-generic/unistd.h
- Change arch/riscv to drop all these ABIs.
Originally, the plan was to also leave these out on C-Sky, but that now
has a glibc port that uses the older interfaces, so we need to leave
them in place.
In
c7d606f560 ("x86/mce: Improve error message when kernel cannot recover")
a case was added for a machine check caused by a DATA access to poison
memory from the kernel. A case should have been added also for an
uncorrectable error during an instruction fetch in the kernel.
Add that extra case so the error message now reads:
mce: [Hardware Error]: Machine check: Instruction fetch error in kernel
Fixes: c7d606f560 ("x86/mce: Improve error message when kernel cannot recover")
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190225205940.15226-1-tony.luck@intel.com
This was caught while staring at the whole {set,get}_fs() machinery.
It's last user, the 32-bit version of strnlen_user() went away with
5723aa993d ("x86: use the new generic strnlen_user() function")
so drop it.
No functional changes.
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: the arch/x86 maintainers <x86@kernel.org>
Cc: "Tobin C. Harding" <tobin@kernel.org>
Link: https://lkml.kernel.org/r/20190225191109.7671-1-bp@alien8.de
When calling __put_user(foo(), ptr), the __put_user() macro would call
foo() in between __uaccess_begin() and __uaccess_end(). If that code
were buggy, then those bugs would be run without SMAP protection.
Fortunately, there seem to be few instances of the problem in the
kernel. Nevertheless, __put_user() should be fixed to avoid doing this.
Therefore, evaluate __put_user()'s argument before setting AC.
This issue was noticed when an objtool hack by Peter Zijlstra complained
about genregs_get() and I compared the assembly output to the C source.
[ bp: Massage commit message and fixed up whitespace. ]
Fixes: 11f1a4b975 ("x86: reorganize SMAP handling in user space accesses")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20190225125231.845656645@infradead.org
This reverts commit 9da3f2b740.
It was well-intentioned, but wrong. Overriding the exception tables for
instructions for random reasons is just wrong, and that is what the new
code did.
It caused problems for tracing, and it caused problems for strncpy_from_user(),
because the new checks made perfectly valid use cases break, rather than
catch things that did bad things.
Unchecked user space accesses are a problem, but that's not a reason to
add invalid checks that then people have to work around with silly flags
(in this case, that 'kernel_uaccess_faults_ok' flag, which is just an
odd way to say "this commit was wrong" and was sprinked into random
places to hide the wrongness).
The real fix to unchecked user space accesses is to get rid of the
special "let's not check __get_user() and __put_user() at all" logic.
Make __{get|put}_user() be just aliases to the regular {get|put}_user()
functions, and make it impossible to access user space without having
the proper checks in places.
The raison d'être of the special double-underscore versions used to be
that the range check was expensive, and if you did multiple user
accesses, you'd do the range check up front (like the signal frame
handling code, for example). But SMAP (on x86) and PAN (on ARM) have
made that optimization pointless, because the _real_ expense is the "set
CPU flag to allow user space access".
Do let's not break the valid cases to catch invalid cases that shouldn't
even exist.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tobin C. Harding <tobin@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Three conflicts, one of which, for marvell10g.c is non-trivial and
requires some follow-up from Heiner or someone else.
The issue is that Heiner converted the marvell10g driver over to
use the generic c45 code as much as possible.
However, in 'net' a bug fix appeared which makes sure that a new
local mask (MDIO_AN_10GBT_CTRL_ADV_NBT_MASK) with value 0x01e0
is cleared.
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, the address range calculation for file-based filters works as
long as the vma that maps the matching part of the object file starts
from offset zero into the file (vm_pgoff==0). Otherwise, the resulting
filter range would be off by vm_pgoff pages. Another related problem is
that in case of a partially matching vma, that is, a vma that matches
part of a filter region, the filter range size wouldn't be adjusted.
Fix the arithmetics around address filter range calculations, taking
into account vma offset, so that the entire calculation is done before
the filter configuration is passed to the PMU drivers instead of having
those drivers do the final bit of arithmetics.
Based on the patch by Adrian Hunter <adrian.hunter.intel.com>.
Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Fixes: 375637bc52 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/20190215115655.63469-3-alexander.shishkin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Previously, commit 7dcd575520 ("x86/kvm/mmu: check if tdp/shadow
MMU reconfiguration is needed") offered some optimization to avoid
the unnecessary reconfiguration. Yet one scenario is broken - when
cpuid changes VM's maximum physical address width, reconfiguration
is needed to reset the reserved bits. Also, the TDP may need to
reset its shadow_root_level when this value is changed.
To fix this, a new field, maxphyaddr, is introduced in the extended
role structure to keep track of the configured guest physical address
width.
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Previously, 'commit 372fddf709 ("x86/mm: Introduce the 'no5lvl' kernel
parameter")' cleared X86_FEATURE_LA57 in boot_cpu_data, if Linux chooses
to not run in 5-level paging mode. Yet boot_cpu_data is queried by
do_cpuid_ent() as the host capability later when creating vcpus, and Qemu
will not be able to detect this feature and create VMs with LA57 feature.
As discussed earlier, VMs can still benefit from extended linear address
width, e.g. to enhance features like ASLR. So we would like to fix this,
by return the true hardware capability when Qemu queries.
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 14c07ad89f ("x86/kvm/mmu: introduce guest_mmu") brought one subtle
change: previously, when switching back from L2 to L1, we were resetting
MMU hooks (like mmu->get_cr3()) in kvm_init_mmu() called from
nested_vmx_load_cr3() and now we do that in nested_ept_uninit_mmu_context()
when we re-target vcpu->arch.mmu pointer.
The change itself looks logical: if nested_ept_init_mmu_context() changes
something than nested_ept_uninit_mmu_context() restores it back. There is,
however, one thing: the following call chain:
nested_vmx_load_cr3()
kvm_mmu_new_cr3()
__kvm_mmu_new_cr3()
fast_cr3_switch()
cached_root_available()
now happens with MMU hooks pointing to the new MMU (root MMU in our case)
while previously it was happening with the old one. cached_root_available()
tries to stash current root but it is incorrect to read current CR3 with
mmu->get_cr3(), we need to use old_mmu->get_cr3() which in case we're
switching from L2 to L1 is guest_mmu. (BTW, in shadow page tables case this
is a non-issue because we don't switch MMU).
While we could've tried to guess that we're switching between MMUs and call
the right ->get_cr3() from cached_root_available() this seems to be overly
complicated. Instead, just stash the corresponding CR3 when setting
root_hpa and make cached_root_available() use the stashed value.
Fixes: 14c07ad89f ("x86/kvm/mmu: introduce guest_mmu")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The invariant TSC bit has the following meaning:
"The time stamp counter in newer processors may support an enhancement,
referred to as invariant TSC. Processor's support for invariant TSC
is indicated by CPUID.80000007H:EDX[8]. The invariant TSC will run
at a constant rate in all ACPI P-, C-. and T-states. This is the
architectural behavior moving forward. On processors with invariant TSC
support, the OS may use the TSC for wall clock timer services (instead
of ACPI or HPET timers). TSC reads are much more efficient and do not
incur the overhead associated with a ring transition or access to a
platform resource."
IOW, TSC does not change frequency. In such case, and with
TSC scaling hardware available to handle migration, it is possible
to use the TSC clocksource directly, whose system calls are
faster.
Reduce the rating of kvmclock clocksource to allow TSC clocksource
to be the default if invariant TSC is exposed.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
v2: Use feature bits and tsc_unstable() check (Sean Christopherson)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...via a new helper, __kvm_mmu_zap_all(). An alternative to passing a
'bool mmio_only' would be to pass a callback function to filter the
shadow page, i.e. to make __kvm_mmu_zap_all() generic and reusable, but
zapping all shadow pages is a last resort, i.e. making the helper less
extensible is a feature of sorts. And the explicit MMIO parameter makes
it easy to preserve the WARN_ON_ONCE() if a restart is triggered when
zapping MMIO sptes.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo expressed a concern that kvm_mmu_zap_mmio_sptes() could have a
quadratic runtime[1], i.e. restarting the spte walk while zapping only
MMIO sptes could result in re-walking large portions of the list over
and over due to the non-MMIO sptes encountered before the restart not
being removed.
At the time, the concern was legitimate as the walk was restarted when
any spte was zapped. But that is no longer the case as the walk is now
restarted iff one or more children have been zapped, which is necessary
because zapping children makes the active_mmu_pages list unstable.
Furthermore, it should be impossible for an MMIO spte to have children,
i.e. zapping an MMIO spte should never result in zapping children. In
other words, kvm_mmu_zap_mmio_sptes() should never restart its walk, and
so should always execute in linear time. WARN if this assertion fails.
Although it should never be needed, leave the restart logic in place.
In normal operation, the cost is at worst an extra CMP+Jcc, and if for
some reason the list does become unstable, not restarting would likely
crash KVM, or worse, the kernel.
[1] https://patchwork.kernel.org/patch/10756589/#22452085
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The return value of kvm_mmu_prepare_zap_page() has evolved to become
overloaded to convey two separate pieces of information. 1) was at
least one page zapped and 2) has the list of MMU pages become unstable.
In it's original incarnation (as kvm_mmu_zap_page()), there was no
return value at all. Commit 0738541396 ("KVM: MMU: awareness of new
kvm_mmu_zap_page behaviour") added a return value in preparation for
commit 4731d4c7a0 ("KVM: MMU: out of sync shadow core"). Although
the return value was of type 'int', it was actually used as a boolean
to indicate whether or not active_mmu_pages may have become unstable due
to zapping children. Walking a list with list_for_each_entry_safe()
only protects against deleting/moving the current entry, i.e. zapping a
child page would break iteration due to modifying any number of entries.
Later, commit 60c8aec6e2 ("KVM: MMU: use page array in unsync walk")
modified mmu_zap_unsync_children() to return an approximation of the
number of children zapped. This was not intentional, it was simply a
side effect of how the code was written.
The unintented side affect was then morphed into an actual feature by
commit 77662e0028 ("KVM: MMU: fix kvm_mmu_zap_page() and its calling
path"), which modified kvm_mmu_change_mmu_pages() to use the number of
zapped pages when determining the number of MMU pages in use by the VM.
Finally, commit 54a4f0239f ("KVM: MMU: make kvm_mmu_zap_page() return
the number of pages it actually freed") added the initial page to the
return value to make its behavior more consistent with what most users
would expect. Incorporating the initial parent page in the return value
of kvm_mmu_zap_page() breaks the original usage of restarting a list
walk on a non-zero return value to handle a potentially unstable list,
i.e. walks will unnecessarily restart when any page is zapped.
Fix this by restoring the original behavior of kvm_mmu_zap_page(), i.e.
return a boolean to indicate that the list may be unstable and move the
number of zapped children to a dedicated parameter. Since the majority
of callers to kvm_mmu_prepare_zap_page() don't care about either return
value, preserve the current definition of kvm_mmu_prepare_zap_page() by
making it a wrapper of a new helper, __kvm_mmu_prepare_zap_page(). This
avoids having to update every call site and also provides cleaner code
for functions that only care about the number of pages zapped.
Fixes: 54a4f0239f ("KVM: MMU: make kvm_mmu_zap_page() return
the number of pages it actually freed")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Remove x86 KVM's fast invalidate mechanism, i.e. revert all patches
from the original series[1], now that all users of the fast invalidate
mechanism are gone.
This reverts commit 5304b8d37c.
[1] https://lkml.kernel.org/r/1369960590-14138-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com
Cc: Xiao Guangrong <guangrong.xiao@gmail.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Call cond_resched_lock() when zapping all sptes to reschedule if needed
or to release and reacquire mmu_lock in case of contention. There is no
need to flush or zap when temporarily dropping mmu_lock as zapping all
sptes is done only when the owning userspace VMM has exited or when the
VM is being destroyed, i.e. there is no interplay with memslots or MMIO
generations to worry about.
Be paranoid and restart the walk if mmu_lock is dropped to avoid any
potential issues with consuming a stale iterator. The overhead in doing
so is negligible as at worst there will be a few root shadow pages at
the head of the list, i.e. the iterator is essentially the head of the
list already.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...to guarantee forward progress. When zapped, root pages are marked
invalid and moved to the head of the active pages list until they are
explicitly freed. Theoretically, having unzappable root pages at the
head of the list could prevent kvm_mmu_zap_all() from making forward
progress were a future patch to add a loop restart after processing a
page, e.g. to drop mmu_lock on contention.
Although kvm_mmu_prepare_zap_page() can theoretically take action on
invalid pages, e.g. to zap unsync children, functionally it's not
necessary (root pages will be re-zapped when freed) and practically
speaking the odds of e.g. @unsync or @unsync_children becoming %true
while zapping all pages is basically nil.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Revert to a slow kvm_mmu_zap_all() for kvm_arch_flush_shadow_all().
Flushing all shadow entries is only done during VM teardown, i.e.
kvm_arch_flush_shadow_all() is only called when the associated MM struct
is being released or when the VM instance is being freed.
Although the performance of teardown itself isn't critical, KVM should
still voluntarily schedule to play nice with the rest of the kernel;
but that can be done without the fast invalidate mechanism in a future
patch.
This reverts commit 6ca18b6950.
Cc: Xiao Guangrong <guangrong.xiao@gmail.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...as part of removing x86 KVM's fast invalidate mechanism, i.e. this
is one part of a revert all patches from the series that introduced the
mechanism[1].
This reverts commit 2248b02321.
[1] https://lkml.kernel.org/r/1369960590-14138-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com
Cc: Xiao Guangrong <guangrong.xiao@gmail.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...as part of removing x86 KVM's fast invalidate mechanism, i.e. this
is one part of a revert all patches from the series that introduced the
mechanism[1].
This reverts commit 35006126f0.
[1] https://lkml.kernel.org/r/1369960590-14138-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com
Cc: Xiao Guangrong <guangrong.xiao@gmail.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Unwinding optimizations related to obsolete pages is a step towards
removing x86 KVM's fast invalidate mechanism, i.e. this is one part of
a revert all patches from the series that introduced the mechanism[1].
This reverts commit e7d11c7a89.
[1] https://lkml.kernel.org/r/1369960590-14138-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com
Cc: Xiao Guangrong <guangrong.xiao@gmail.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Unwinding optimizations related to obsolete pages is a step towards
removing x86 KVM's fast invalidate mechanism, i.e. this is one part of
a revert all patches from the series that introduced the mechanism[1].
This reverts commit f34d251d66.
[1] https://lkml.kernel.org/r/1369960590-14138-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com
Cc: Xiao Guangrong <guangrong.xiao@gmail.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Unwinding optimizations related to obsolete pages is a step towards
removing x86 KVM's fast invalidate mechanism, i.e. this is one part of
a revert all patches from the series that introduced the mechanism[1].
This reverts commit 365c886860.
[1] https://lkml.kernel.org/r/1369960590-14138-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com
Cc: Xiao Guangrong <guangrong.xiao@gmail.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Unwinding usage of is_obsolete() is a step towards removing x86's fast
invalidate mechanism, i.e. this is one part of a revert all patches from
the series that introduced the mechanism[1].
This is a partial revert of commit 05988d728d ("KVM: MMU: reduce
KVM_REQ_MMU_RELOAD when root page is zapped").
[1] https://lkml.kernel.org/r/1369960590-14138-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com
Cc: Xiao Guangrong <guangrong.xiao@gmail.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Call cond_resched_lock() when zapping MMIO to reschedule if needed or to
release and reacquire mmu_lock in case of contention. There is no need
to flush or zap when temporarily dropping mmu_lock as zapping MMIO sptes
is done when holding the memslots lock and with the "update in-progress"
bit set in the memslots generation, which disables MMIO spte caching.
The walk does need to be restarted if mmu_lock is dropped as the active
pages list may be modified.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Revert back to a dedicated (and slower) mechanism for handling the
scenario where all MMIO shadow PTEs need to be zapped due to overflowing
the MMIO generation number. The MMIO generation scenario is almost
literally a one-in-a-million occurrence, i.e. is not a performance
sensitive scenario.
Restoring kvm_mmu_zap_mmio_sptes() leaves VM teardown as the only user
of kvm_mmu_invalidate_zap_all_pages() and paves the way for removing
the fast invalidate mechanism altogether.
This reverts commit a8eca9dcc6.
Cc: Xiao Guangrong <guangrong.xiao@gmail.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Remove x86 KVM's fast invalidate mechanism, i.e. revert all patches
from the original series[1].
Though not explicitly stated, for all intents and purposes the fast
invalidate mechanism was added to speed up the scenario where removing
a memslot, e.g. as part of accessing reading PCI ROM, caused KVM to
flush all shadow entries[1]. Now that the memslot case flushes only
shadow entries belonging to the memslot, i.e. doesn't use the fast
invalidate mechanism, the only remaining usage of the mechanism are
when the VM is being destroyed and when the MMIO generation rolls
over.
When a VM is being destroyed, either there are no active vcpus, i.e.
there's no lock contention, or the VM has ungracefully terminated, in
which case we want to reclaim its pages as quickly as possible, i.e.
not release the MMU lock if there are still CPUs executing in the VM.
The MMIO generation scenario is almost literally a one-in-a-million
occurrence, i.e. is not a performance sensitive scenario.
Given that lock-breaking is not desirable (VM teardown) or irrelevant
(MMIO generation overflow), remove the fast invalidate mechanism to
simplify the code (a small amount) and to discourage future code from
zapping all pages as using such a big hammer should be a last restort.
This reverts commit f6f8adeef5.
[1] https://lkml.kernel.org/r/1369960590-14138-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com
Cc: Xiao Guangrong <guangrong.xiao@gmail.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Modify kvm_mmu_invalidate_zap_pages_in_memslot(), a.k.a. the x86 MMU's
handler for kvm_arch_flush_shadow_memslot(), to zap only the pages/PTEs
that actually belong to the memslot being removed. This improves
performance, especially why the deleted memslot has only a few shadow
entries, or even no entries. E.g. a microbenchmark to access regular
memory while concurrently reading PCI ROM to trigger memslot deletion
showed a 5% improvement in throughput.
Cc: Xiao Guangrong <guangrong.xiao@gmail.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...and into a separate helper, kvm_mmu_remote_flush_or_zap(), that does
not require a vcpu so that the code can be (re)used by
kvm_mmu_invalidate_zap_pages_in_memslot().
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...so that kvm_mmu_invalidate_zap_pages_in_memslot() can utilize the
helpers in future patches.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...now that KVM won't explode by moving it out of bit 0. Using bit 63
eliminates the need to jump over bit 0, e.g. when calculating a new
memslots generation or when propagating the memslots generation to an
MMIO spte.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The code to propagate the memslots generation number into MMIO sptes is
a bit convoluted. The "what" is relatively straightfoward, e.g. the
comment explaining which bits go where is quite readable, but the "how"
requires a lot of staring to understand what is happening. For example,
'MMIO_GEN_LOW_SHIFT' is actually used to calculate the high bits of the
spte, while 'MMIO_SPTE_GEN_LOW_SHIFT' is used to calculate the low bits.
Refactor the code to:
- use #defines whose values align with the bits defined in the comment
- use consistent code for both the high and low mask
- explicitly highlight the handling of bit 0 (update in-progress flag)
- explicitly call out that the defines are for MMIO sptes (to avoid
confusion with the per-vCPU MMIO cache, which uses the full memslots
generation)
In addition to making the code a little less magical, this paves the way
for moving the update in-progress flag to bit 63 without having to
simultaneously rewrite all of the MMIO spte code.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM currently uses an 'unsigned int' for the MMIO generation number
despite it being derived from the 64-bit memslots generation and
being propagated to (potentially) 64-bit sptes. There is no hidden
agenda behind using an 'unsigned int', it's done simply because the
MMIO generation will never set bits above bit 19.
Passing a u64 will allow the "update in-progress" flag to be relocated
from bit 0 to bit 63 and removes the need to cast the generation back
to a u64 when propagating it to a spte.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM uses bit 0 of the memslots generation as an "update in-progress"
flag, which is used by x86 to prevent caching MMIO access while the
memslots are changing. Although the intended behavior is flag-like,
e.g. MMIO sptes intentionally drop the in-progress bit so as to avoid
caching data from in-flux memslots, the implementation oftentimes treats
the bit as part of the generation number itself, e.g. incrementing the
generation increments twice, once to set the flag and once to clear it.
Prior to commit 4bd518f159 ("KVM: use separate generations for
each address space"), incorporating the "update in-progress" bit into
the generation number largely made sense, e.g. "real" generations are
even, "bogus" generations are odd, most code doesn't need to be aware of
the bit, etc...
Now that unique memslots generation numbers are assigned to each address
space, stealthing the in-progress status into the generation number
results in a wide variety of subtle code, e.g. kvm_create_vm() jumps
over bit 0 when initializing the memslots generation without any hint as
to why.
Explicitly define the flag and convert as much code as possible (which
isn't much) to actually treat it like a flag. This paves the way for
eventually using a different bit for "update in-progress" so that it can
be a flag in truth instead of a awkward extension to the generation
number.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When installing new memslots, KVM sets bit 0 of the generation number to
indicate that an update is in-progress. Until the update is complete,
there are no guarantees as to whether a vCPU will see the old or the new
memslots. Explicity prevent caching MMIO accesses so as to avoid using
an access cached from the old memslots after the new memslots have been
installed.
Note that it is unclear whether or not disabling caching during the
update window is strictly necessary as there is no definitive
documentation as to what ordering guarantees KVM provides with respect
to updating memslots. That being said, the MMIO spte code does not
allow reusing sptes created while an update is in-progress, and the
associated documentation explicitly states:
We do not want to use an MMIO sptes created with an odd generation
number, ... If KVM is unlucky and creates an MMIO spte while the
low bit is 1, the next access to the spte will always be a cache miss.
At the very least, disabling the per-vCPU MMIO cache during updates will
make its behavior consistent with the MMIO spte behavior and
documentation.
Fixes: 56f17dd3fb ("kvm: x86: fix stale mmio cache bug")
Cc: <stable@vger.kernel.org>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The check to detect a wrap of the MMIO generation explicitly looks for a
generation number of zero. Now that unique memslots generation numbers
are assigned to each address space, only address space 0 will get a
generation number of exactly zero when wrapping. E.g. when address
space 1 goes from 0x7fffe to 0x80002, the MMIO generation number will
wrap to 0x2. Adjust the MMIO generation to strip the address space
modifier prior to checking for a wrap.
Fixes: 4bd518f159 ("KVM: use separate generations for each address space")
Cc: <stable@vger.kernel.org>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm_arch_memslots_updated() is at this point in time an x86-specific
hook for handling MMIO generation wraparound. x86 stashes 19 bits of
the memslots generation number in its MMIO sptes in order to avoid
full page fault walks for repeat faults on emulated MMIO addresses.
Because only 19 bits are used, wrapping the MMIO generation number is
possible, if unlikely. kvm_arch_memslots_updated() alerts x86 that
the generation has changed so that it can invalidate all MMIO sptes in
case the effective MMIO generation has wrapped so as to avoid using a
stale spte, e.g. a (very) old spte that was created with generation==0.
Given that the purpose of kvm_arch_memslots_updated() is to prevent
consuming stale entries, it needs to be called before the new generation
is propagated to memslots. Invalidating the MMIO sptes after updating
memslots means that there is a window where a vCPU could dereference
the new memslots generation, e.g. 0, and incorrectly reuse an old MMIO
spte that was created with (pre-wrap) generation==0.
Fixes: e59dbe09f8 ("KVM: Introduce kvm_arch_memslots_updated()")
Cc: <stable@vger.kernel.org>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There are many KVM kernel memory allocations which are tied to the life of
the VM process and should be charged to the VM process's cgroup. If the
allocations aren't tied to the process, the OOM killer will not know
that killing the process will free the associated kernel memory.
Add __GFP_ACCOUNT flags to many of the allocations which are not yet being
charged to the VM process's cgroup.
Tested:
Ran all kvm-unit-tests on a 64 bit Haswell machine, the patch
introduced no new failures.
Ran a kernel memory accounting test which creates a VM to touch
memory and then checks that the kernel memory allocated for the
process is within certain bounds.
With this patch we account for much more of the vmalloc and slab memory
allocated for the VM.
Signed-off-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There are many KVM kernel memory allocations which are tied to the life of
the VM process and should be charged to the VM process's cgroup. If the
allocations aren't tied to the process, the OOM killer will not know
that killing the process will free the associated kernel memory.
Add __GFP_ACCOUNT flags to many of the allocations which are not yet being
charged to the VM process's cgroup.
Tested:
Ran all kvm-unit-tests on a 64 bit Haswell machine, the patch
introduced no new failures.
Ran a kernel memory accounting test which creates a VM to touch
memory and then checks that the kernel memory allocated for the
process is within certain bounds.
With this patch we account for much more of the vmalloc and slab memory
allocated for the VM.
Signed-off-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There are many KVM kernel memory allocations which are tied to the life of
the VM process and should be charged to the VM process's cgroup. If the
allocations aren't tied to the process, the OOM killer will not know
that killing the process will free the associated kernel memory.
Add __GFP_ACCOUNT flags to many of the allocations which are not yet being
charged to the VM process's cgroup.
Tested:
Ran all kvm-unit-tests on a 64 bit Haswell machine, the patch
introduced no new failures.
Ran a kernel memory accounting test which creates a VM to touch
memory and then checks that the kernel memory allocated for the
process is within certain bounds.
With this patch we account for much more of the vmalloc and slab memory
allocated for the VM.
There remain a few allocations which should be charged to the VM's
cgroup but are not. In x86, they include:
vcpu->arch.pio_data
There allocations are unaccounted in this patch because they are mapped
to userspace, and accounting them to a cgroup causes problems. This
should be addressed in a future patch.
Signed-off-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The preemption timer can be started even if there is a vmentry
failure during or after loading guest state. That is pointless,
move the call after all conditions have been checked.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Previously, 'commit f99e3daf94 ("KVM: x86: Add Intel PT
virtualization work mode")' work mode' offered framework
to support Intel PT virtualization. However, the patch has
some typos in vmx_vmentry_ctrl() and vmx_vmexit_ctrl(), e.g.
used wrong flags and wrong variable, which will cause the
VM entry failure later.
Fixes: 'commit f99e3daf94 ("KVM: x86: Add Intel PT virtualization work mode")'
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Ensure that the VCPU free path goes through vmx_leave_nested and
thus nested_vmx_vmexit, so that the cancellation of the timer does
not have to be in free_nested. In addition, because some paths through
nested_vmx_vmexit do not go through sync_vmcs12, the cancellation of
the timer is moved there.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Some Posted-Interrupts from passthrough devices may be lost or
overwritten when the vCPU is in runnable state.
The SN (Suppress Notification) of PID (Posted Interrupt Descriptor) will
be set when the vCPU is preempted (vCPU in KVM_MP_STATE_RUNNABLE state
but not running on physical CPU). If a posted interrupt coming at this
time, the irq remmaping facility will set the bit of PIR (Posted
Interrupt Requests) without ON (Outstanding Notification).
So this interrupt can't be sync to APIC virtualization register and
will not be handled by Guest because ON is zero.
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
[Eliminate the pi_clear_sn fast path. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
MOVDIR64B moves 64-bytes as direct-store with 64-bytes write atomicity.
Direct store is implemented by using write combining (WC) for writing
data directly into memory without caching the data.
Availability of the MOVDIR64B instruction is indicated by the presence
of the CPUID feature flag MOVDIR64B (CPUID.0x07.0x0:ECX[bit 28]).
This patch exposes the movdir64b feature to the guest.
The release document ref below link:
https://software.intel.com/sites/default/files/managed/c5/15/\
architecture-instruction-set-extensions-programming-reference.pdf
Signed-off-by: Liu Jingqi <jingqi.liu@intel.com>
Cc: Xu Tao <tao3.xu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
MOVDIRI moves doubleword or quadword from register to memory through
direct store which is implemented by using write combining (WC) for
writing data directly into memory without caching the data.
Availability of the MOVDIRI instruction is indicated by the presence of
the CPUID feature flag MOVDIRI(CPUID.0x07.0x0:ECX[bit 27]).
This patch exposes the movdiri feature to the guest.
The release document ref below link:
https://software.intel.com/sites/default/files/managed/c5/15/\
architecture-instruction-set-extensions-programming-reference.pdf
Signed-off-by: Liu Jingqi <jingqi.liu@intel.com>
Cc: Xu Tao <tao3.xu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
AMD's SME/SEV is no longer the only case which reduces supported
physical address bits, since Intel introduced Multi-key Total Memory
Encryption (MKTME), which repurposes high bits of physical address as
keyID, thus effectively shrinks supported physical address bits. To
cover both cases (and potential similar future features), kernel MM
introduced generic dynamaic physical address mask instead of hard-coded
__PHYSICAL_MASK in 'commit 94d49eb30e ("x86/mm: Decouple dynamic
__PHYSICAL_MASK from AMD SME")'. KVM should use that too.
Change PT64_BASE_ADDR_MASK to use kernel dynamic physical address mask
when it is enabled, instead of sme_clr. PT64_DIR_BASE_ADDR_MASK is also
deleted since it is not used at all.
Signed-off-by: Kai Huang <kai.huang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
VMX is only accessible in protected mode, remove a confusing check
that causes the conditional to lack a final "else" branch.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Regarding segments with a limit==0xffffffff, the SDM officially states:
When the effective limit is FFFFFFFFH (4 GBytes), these accesses may
or may not cause the indicated exceptions. Behavior is
implementation-specific and may vary from one execution to another.
In practice, all CPUs that support VMX ignore limit checks for "flat
segments", i.e. an expand-up data or code segment with base=0 and
limit=0xffffffff. This is subtly different than wrapping the effective
address calculation based on the address size, as the flat segment
behavior also applies to accesses that would wrap the 4g boundary, e.g.
a 4-byte access starting at 0xffffffff will access linear addresses
0xffffffff, 0x0, 0x1 and 0x2.
Fixes: f9eb4af67c ("KVM: nVMX: VMX instructions: add checks for #GP/#SS exceptions")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The address size of an instruction affects the effective address, not
the virtual/linear address. The final address may still be truncated,
e.g. to 32-bits outside of long mode, but that happens irrespective of
the address size, e.g. a 32-bit address size can yield a 64-bit virtual
address when using FS/GS with a non-zero base.
Fixes: 064aea7747 ("KVM: nVMX: Decoding memory operands of VMX instructions")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The VMCS.EXIT_QUALIFCATION field reports the displacements of memory
operands for various instructions, including VMX instructions, as a
naturally sized unsigned value, but masks the value by the addr size,
e.g. given a ModRM encoded as -0x28(%ebp), the -0x28 displacement is
reported as 0xffffffd8 for a 32-bit address size. Despite some weird
wording regarding sign extension, the SDM explicitly states that bits
beyond the instructions address size are undefined:
In all cases, bits of this field beyond the instruction’s address
size are undefined.
Failure to sign extend the displacement results in KVM incorrectly
treating a negative displacement as a large positive displacement when
the address size of the VMX instruction is smaller than KVM's native
size, e.g. a 32-bit address size on a 64-bit KVM.
The very original decoding, added by commit 064aea7747 ("KVM: nVMX:
Decoding memory operands of VMX instructions"), sort of modeled sign
extension by truncating the final virtual/linear address for a 32-bit
address size. I.e. it messed up the effective address but made it work
by adjusting the final address.
When segmentation checks were added, the truncation logic was kept
as-is and no sign extension logic was introduced. In other words, it
kept calculating the wrong effective address while mostly generating
the correct virtual/linear address. As the effective address is what's
used in the segment limit checks, this results in KVM incorreclty
injecting #GP/#SS faults due to non-existent segment violations when
a nested VMM uses negative displacements with an address size smaller
than KVM's native address size.
Using the -0x28(%ebp) example, an EBP value of 0x1000 will result in
KVM using 0x100000fd8 as the effective address when checking for a
segment limit violation. This causes a 100% failure rate when running
a 32-bit KVM build as L1 on top of a 64-bit KVM L0.
Fixes: f9eb4af67c ("KVM: nVMX: VMX instructions: add checks for #GP/#SS exceptions")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The function svm_refresh_apicv_exec_ctrl() always returning prematurely
as kvm_vcpu_apicv_active() always return false when calling from
the function arch/x86/kvm/x86.c:kvm_vcpu_deactivate_apicv().
This is because the apicv_active is set to false just before calling
refresh_apicv_exec_ctrl().
Also, we need to mark VMCB_AVIC bit as dirty instead of VMCB_INTR.
So, fix svm_refresh_apicv_exec_ctrl() to properly deactivate AVIC.
Fixes: 67034bb9dd ('KVM: SVM: Add irqchip_split() checks before enabling AVIC')
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently apicv_active can be true even if in-kernel LAPIC
emulation is disabled. Avoid this by properly initializing
it in kvm_arch_vcpu_init, and then do not do anything to
deactivate APICv when it is actually not used
(Currently APICv is only deactivated by SynIC code that in turn
is only reachable when in-kernel LAPIC is in use. However, it is
cleaner if kvm_vcpu_deactivate_apicv avoids relying on this.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Current SVM AVIC driver makes two incorrect assumptions:
1. APIC LDR register cannot be zero
2. APIC DFR for all vCPUs must be the same
LDR=0 means the local APIC does not support logical destination mode.
Therefore, the driver should mark any previously assigned logical APIC ID
table entry as invalid, and return success. Also, DFR is specific to
a particular local APIC, and can be different among all vCPUs
(as observed on Windows 10).
These incorrect assumptions cause Windows 10 and FreeBSD VMs to fail
to boot with AVIC enabled. So, instead of flush the whole logical APIC ID
table, handle DFR and LDR for each vCPU independently.
Fixes: 18f40c53e1 ('svm: Add VMEXIT handlers for AVIC')
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reported-by: Julian Stecklina <jsteckli@amazon.de>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
VMs may show incorrect uptime and dmesg printk offsets on hypervisors with
unstable clock. The problem is produced when VM is rebooted without exiting
from qemu.
The fix is to calculate clock offset not only for stable clock but for
unstable clock as well, and use kvm_sched_clock_read() which substracts
the offset for both clocks.
This is safe, because pvclock_clocksource_read() does the right thing and
makes sure that clock always goes forward, so once offset is calculated
with unstable clock, we won't get new reads that are smaller than offset,
and thus won't get negative results.
Thank you Jon DeVree for helping to reproduce this issue.
Fixes: 857baa87b6 ("sched/clock: Enable sched clock early")
Cc: stable@vger.kernel.org
Reported-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the clearing of the common registers (not 64-bit-only) to the start
of the flow that clears registers holding guest state. This is
purely a cosmetic change so that the label doesn't point at a blank line
and a #define.
No functional change intended.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...now that the sub-routine follows standard calling conventions.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...to make it callable from C code.
Note that because KVM chooses to be ultra paranoid about guest register
values, all callee-save registers are still cleared after VM-Exit even
though the host's values are now reloaded from the stack.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...to prepare for making the assembly sub-routine callable from C code.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...to prepare for making the sub-routine callable from C code.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...to prepare for making the sub-routine callable from C code. That
means returning the result in RAX. Since RAX will be used to return the
result, use it as the scratch register as well to make the code readable
and to document that the scratch register is more or less arbitrary.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...now that the name is no longer usurped by a defunct helper function.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...now that the code is no longer tagged with STACK_FRAME_NON_STANDARD.
Arguably, providing __vmx_vcpu_run() to break up vmx_vcpu_run() is
valuable on its own, but the previous split was purposely made as small
as possible to limit the effects STACK_FRAME_NON_STANDARD. In other
words, the current split is now completely arbitrary and likely not the
most logical.
This also allows renaming ____vmx_vcpu_run() to __vmx_vcpu_run() in a
future patch.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
As evidenced by the myriad patches leading up to this moment, using
an inline asm blob for vCPU-run is nothing short of horrific. It's also
been called "unholy", "an abomination" and likely a whole host of other
names that would violate the Code of Conduct if recorded here and now.
The code is relocated nearly verbatim, e.g. quotes, newlines, tabs and
__stringify need to be dropped, but other than those cosmetic changes
the only functional changees are to add the "call" and replace the final
"jmp" with a "ret".
Note that STACK_FRAME_NON_STANDARD is also dropped from __vmx_vcpu_run().
Suggested-by: Andi Kleen <ak@linux.intel.com>
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...in preparation for moving to a proper assembly sub-routnine.
vCPU-run isn't a leaf function since it calls vmx_update_host_rsp()
and vmx_vmenter(). And since we need to save/restore RBP anyways,
unconditionally creating the frame costs a single MOV, i.e. don't
bother keying off CONFIG_FRAME_POINTER or using FRAME_BEGIN, etc...
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...to prepare for moving the inline asm to a proper asm sub-routine.
Eliminating the immediates allows a nearly verbatim move, e.g. quotes,
newlines, tabs and __stringify need to be dropped, but other than those
cosmetic changes the only function change will be to replace the final
"jmp" with a "ret".
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Declaring the VCPU_REGS_* as enums allows for more robust C code, but it
prevents using the values in assembly files. Expliciting #define the
indices in an asm-friendly file to prepare for VMX moving its transition
code to a proper assembly file, but keep the enums for general usage.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This API is primarily used through DT entries, but two architectures
and two drivers call it directly. So instead of selecting the config
symbol for random architectures pull it in implicitly for the actual
users. Also rename the Kconfig option to describe the feature better.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Paul Burton <paul.burton@mips.com> # MIPS
Acked-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All new 32-bit architectures should have 64-bit userspace off_t type, but
existing architectures has 32-bit ones.
To enforce the rule, new config option is added to arch/Kconfig that defaults
ARCH_32BIT_OFF_T to be disabled for new 32-bit architectures. All existing
32-bit architectures enable it explicitly.
New option affects force_o_largefile() behaviour. Namely, if userspace
off_t is 64-bits long, we have no reason to reject user to open big files.
Note that even if architectures has only 64-bit off_t in the kernel
(arc, c6x, h8300, hexagon, nios2, openrisc, and unicore32),
a libc may use 32-bit off_t, and therefore want to limit the file size
to 4GB unless specified differently in the open flags.
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Yury Norov <ynorov@marvell.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Use linux/mman.h to make sure we get all mmap flags we need.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The 'phys_id' local variable became unused after commit
ce4b1b1650 ("x86/smpboot: Initialize secondary CPU only if master CPU will wait for it").
Remove it.
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: Yazen Ghannam <yazen.ghannam@amd.com>
Cc: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Link: https://lkml.kernel.org/r/1550495101-41755-1-git-send-email-zhangshaokun@hisilicon.com
When limiting memory size via kernel parameter "mem=" this should be
respected even in case of memory made accessible via a PCI card.
Today this kind of memory won't be made usable in initial memory
setup as the memory won't be visible in E820 map, but it might be
added when adding PCI devices due to corresponding ACPI table entries.
Not respecting "mem=" can be corrected by adding a global max_mem_size
variable set by parse_memopt() which will result in rejecting adding
memory areas resulting in a memory size above the allowed limit.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Pull x86 fixes from Ingo Molnar:
"Three changes:
- An UV fix/quirk to pull UV BIOS calls into the efi_runtime_lock
locking regime. (This done by aliasing __efi_uv_runtime_lock to
efi_runtime_lock, which should make the quirk nature obvious and
maintain the general policy that the EFI lock (name...) isn't
exposed to drivers.)
- Our version of MAGA: Make a.out Great Again.
- Add a new Intel model name enumerator to an upstream header to help
reduce dependencies going forward"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls
x86/CPU: Add Icelake model number
x86/a.out: Clear the dump structure initially
Pull perf fixes from Ingo Molnar:
"Two fixes on the kernel side: fix an over-eager condition that failed
larger perf ring-buffer sizes, plus fix crashes in the Intel BTS code
for a corner case, found by fuzzing"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix impossible ring-buffer sizes warning
perf/x86: Add check_period PMU callback
The following commit:
a893ea15d764 ("tpm: move tpm_chip definition to include/linux/tpm.h")
introduced a build error when both IMA and EFI are enabled:
In file included from ../security/integrity/ima/ima_fs.c:30:
../security/integrity/ima/ima.h:176:7: error: redeclaration of enumerator "NONE"
What happens is that both headers (ima.h and efi.h) defines the same
'NONE' constant, and it broke when they started getting included from
the same file:
Rework to prefix the EFI enum with 'EFI_*'.
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190215165551.12220-2-ard.biesheuvel@linaro.org
[ Cleaned up the changelog a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The netfilter conflicts were rather simple overlapping
changes.
However, the cls_tcindex.c stuff was a bit more complex.
On the 'net' side, Cong is fixing several races and memory
leaks. Whilst on the 'net-next' side we have Vlad adding
the rtnl-ness support.
What I've decided to do, in order to resolve this, is revert the
conversion over to using a workqueue that Cong did, bringing us back
to pure RCU. I did it this way because I believe that either Cong's
races don't apply with have Vlad did things, or Cong will have to
implement the race fix slightly differently.
Signed-off-by: David S. Miller <davem@davemloft.net>
Previous AMD systems have had a bit in MCA_STATUS to indicate that an
error was detected on a scrub operation. However, this bit was defined
differently within different banks and families/models.
Starting with Family 17h, MCA_STATUS[40] is either Reserved/Read-as-Zero
or defined as "Scrub", for all MCA banks and CPU models. Therefore, this
bit can be defined as the "Scrub" bit.
Define MCA_STATUS[40] as "Scrub" and decode it in the AMD MCE decoding
module for Family 17h and newer systems.
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morse <james.morse@arm.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190212212417.107049-1-Yazen.Ghannam@amd.com
Commit ca83b4a7f2 ("x86/KVM/VMX: Add find_msr() helper function")
introduces the helper function find_msr(), which returns -ENOENT when
not find the msr in vmx->msr_autoload.guest/host. Correct checking contion
of no more available entry in vmx->msr_autoload.
Fixes: ca83b4a7f2 ("x86/KVM/VMX: Add find_msr() helper function")
Cc: stable@vger.kernel.org
Signed-off-by: Xiaoyao Li <xiaoyao.li@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Some Posted-Interrupts from passthrough devices may be lost or
overwritten when the vCPU is in runnable state.
The SN (Suppress Notification) of PID (Posted Interrupt Descriptor) will
be set when the vCPU is preempted (vCPU in KVM_MP_STATE_RUNNABLE state but
not running on physical CPU). If a posted interrupt comes at this time,
the irq remapping facility will set the bit of PIR (Posted Interrupt
Requests) but not ON (Outstanding Notification). Then, the interrupt
will not be seen by KVM, which always expects PID.ON=1 if PID.PIR=1
as documented in the Intel processor SDM but not in the VT-d specification.
To fix this, restore the invariant after PID.SN is cleared.
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add the CPUID model number of Icelake (ICL) mobile processors to the
Intel family list. Icelake U/Y series uses model number 0x7E.
Signed-off-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David E. Box" <david.e.box@intel.com>
Cc: dvhart@infradead.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: platform-driver-x86@vger.kernel.org
Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190214115712.19642-2-rajneesh.bhardwaj@linux.intel.com
A recently added preemption timer consistency check was unintentionally
dropped when the consistency checks were being reorganized to match the
SDM's ordering.
Fixes: 461b4ba4c7 ("KVM: nVMX: Move the checks for VM-Execution Control Fields to a separate helper function")
Cc: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Guenter Roeck reported triple faults of a 64-bit VM using a 32-bit OVMF
EFI image. After some singlestepping of the image in gdb, it turned out
that some of the EFI config tables were at bogus addresses. Which, as
Ard pointed out, results from using the wrong efi_config_table typedef.
So switch all EFI table pointers to unsigned longs and convert them to
the proper typedef only when accessing them. This way, the proper table
type is being used.
Shorten variable names, while at it.
Fixes: 33f0df8d84 ("x86/boot: Search for RSDP in the EFI tables")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: bhe@redhat.com
Cc: caoj.fnst@cn.fujitsu.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: indou.takao@jp.fujitsu.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: kasong@redhat.com
Cc: Kees Cook <keescook@chromium.org>
Cc: msys.mizuma@gmail.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190208190248.GA10854@roeck-us.net
dump_thread32() in aout_core_dump() does not clear the user32 structure
allocated on the stack as the first thing on function entry.
As a result, the dump.u_comm, dump.u_ar0 and dump.signal which get
assigned before the clearing, get overwritten.
Rename that function to fill_dump() to make it clear what it does and
call it first thing.
This was caught while staring at a patch by Derek Robson
<robsonde@gmail.com>.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Derek Robson <robsonde@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Matz <matz@suse.de>
Cc: x86@kernel.org
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20190202005512.3144-1-robsonde@gmail.com
Prohibit probing on the functions called before kprobe_int3_handler()
in do_int3(). More specifically, ftrace_int3_handler(),
poke_int3_handler(), and ist_enter(). And since rcu_nmi_enter() is
called by ist_enter(), it also should be marked as NOKPROBE_SYMBOL.
Since those are handled before kprobe_int3_handler(), probing those
functions can cause a breakpoint recursion and crash the kernel.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/154998793571.31052.11301258949601150994.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Move optprobe trampoline code into RODATA since it is
not executed, but copied and modified to be used on
a trampoline buffer.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/154998790744.31052.3016106262944915510.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Prohibit probing on optprobe template code, since it is not
a code but a template instruction sequence. If we modify
this template, copied template must be broken.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: 9326638cbe ("kprobes, x86: Use NOKPROBE_SYMBOL() instead of __kprobes annotation")
Link: http://lkml.kernel.org/r/154998787911.31052.15274376330136234452.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
SDM says MSR_IA32_VMX_PROCBASED_CTLS2 is only available "If
(CPUID.01H:ECX.[5] && IA32_VMX_PROCBASED_CTLS[63])". It was found that
some old cpus (namely "Intel(R) Core(TM)2 CPU 6600 @ 2.40GHz (family: 0x6,
model: 0xf, stepping: 0x6") don't have it. Add the missing check.
Reported-by: Zdenek Kaspar <zkaspar82@gmail.com>
Tested-by: Zdenek Kaspar <zkaspar82@gmail.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...now that all other references to struct vcpu_vmx have been removed.
Note that 'vmx' still needs to be passed into the asm blob in _ASM_ARG1
as it is consumed by vmx_update_host_rsp(). And similar to that code,
use _ASM_ARG2 in the assembly code to prepare for moving to proper asm,
while explicitly referencing the exact registers in the clobber list for
clarity in the short term and to avoid additional precompiler games.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A failed VM-Enter (obviously) didn't succeed, meaning the CPU never
executed an instrunction in guest mode and so can't have changed the
general purpose registers.
In addition to saving some instructions in the VM-Fail case, this also
provides a separate path entirely and thus an opportunity to propagate
the fail condition to vmx->fail via register without introducing undue
pain. Using a register, as opposed to directly referencing vmx->fail,
eliminates the need to pass the offset of 'fail', which will simplify
moving the code to proper assembly in future patches.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Switching the ordering allows for an out-of-line path for VM-Fail
that elides saving guest state but still shares the register clearing
with the VM-Exit path.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...and remove struct vcpu_vmx's temporary __launched variable.
Eliminating __launched is a bonus, the real motivation is to get to the
point where the only reference to struct vcpu_vmx in the asm code is
to vcpu.arch.regs, which will simplify moving the blob to a proper asm
file. Note that also means this approach is deliberately different than
what is used in nested_vmx_check_vmentry_hw().
Use BL as it is a callee-save register in both 32-bit and 64-bit ABIs,
i.e. it can't be modified by vmx_update_host_rsp(), to avoid having to
temporarily save/restore the launched flag.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Providing a helper function to update HOST_RSP is visibly easier to
read, and more importantly (for the future) eliminates two arguments to
the VM-Enter assembly blob. Reducing the number of arguments to the asm
blob is for all intents and purposes a prerequisite to moving the code
to a proper assembly routine. It's not truly mandatory, but it greatly
simplifies the future code, and the cost of the extra CALL+RET is
negligible in the grand scheme.
Note that although _ASM_ARG[1-3] can be used in the inline asm itself,
the intput/output constraints need to be manually defined. gcc will
actually compile with _ASM_ARG[1-3] specified as constraints, but what
it actually ends up doing with the bogus constraint is unknown.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
...to eliminate its parameter and struct vcpu_vmx offset definition
from the assembly blob. Accessing CR2 from C versus assembly doesn't
change the likelihood of taking a page fault (and modifying CR2) while
it's loaded with the guest's value, so long as we don't do anything
silly between accessing CR2 and VM-Enter/VM-Exit.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, host_rsp is cached on a per-vCPU basis, i.e. it's stored in
struct vcpu_vmx. In non-nested usage the caching is for all intents
and purposes 100% effective, e.g. only the first VMLAUNCH needs to
synchronize VMCS.HOST_RSP since the call stack to vmx_vcpu_run() is
identical each and every time. But when running a nested guest, KVM
must invalidate the cache when switching the current VMCS as it can't
guarantee the new VMCS has the same HOST_RSP as the previous VMCS. In
other words, the cache loses almost all of its efficacy when running a
nested VM.
Move host_rsp to struct vmcs_host_state, which is per-VMCS, so that it
is cached on a per-VMCS basis and restores its 100% hit rate when
nested VMs are in play.
Note that the host_rsp cache for vmcs02 essentially "breaks" when
nested early checks are enabled as nested_vmx_check_vmentry_hw() will
see a different RSP at the time of its VM-Enter. While it's possible
to avoid even that VMCS.HOST_RSP synchronization, e.g. by employing a
dedicated VM-Exit stack, there is little motivation for doing so as
the overhead of two VMWRITEs (~55 cycles) is dwarfed by the overhead
of the extra VMX transition (600+ cycles) and is a proverbial drop in
the ocean relative to the total cost of a nested transtion (10s of
thousands of cycles).
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Qian Cai