Some subsystems (KVM for example) need access to a cycle counter.
In the KVM case, this is used to measure the time delta between
host and guest in order to accurately generate timer events for
the guest.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
At the moment, the arch_timer driver only uses the physical timer,
which can cause problem if PL2 hasn't enabled PL1 access in CNTHCTL,
which is likely in a virtualized environment. Instead, the virtual
timer is always available.
This patch enables the use of the virtual timer, unless no
interrupt is provided in the DT for it, in which case it falls
back to the physical timer.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Many clocks that are used to provide sched_clock will reset during
suspend. If read_sched_clock returns 0 after suspend, sched_clock will
appear to jump forward. This patch resets cd.epoch_cyc to the current
value of read_sched_clock during resume, which causes sched_clock() just
after suspend to return the same value as sched_clock() just before
suspend.
In addition, during the window where epoch_ns has been updated before
suspend, but epoch_cyc has not been updated after suspend, it is unknown
whether the clock has reset or not, and sched_clock() could return a
bogus value. Add a suspended flag, and return the pre-suspend epoch_ns
value during this period.
The new behavior is triggered by calling setup_sched_clock_needs_suspend
instead of setup_sched_clock.
Signed-off-by: Colin Cross <ccross@android.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Get rid of this warning..
arch/arm/kernel/built-in.o(.text+0xac78): Section mismatch in reference
from the function init_cpu_topology() to the function
.init.text:parse_dt_topology()
The function init_cpu_topology() references
the function __init parse_dt_topology().
This is often because init_cpu_topology lacks a __init
annotation or the annotation of parse_dt_topology is wrong.
Signed-off-by: Venkatraman S <svenkatr@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM audit/signal updates from Russell King:
"ARM audit/signal handling updates from Al and Will. This improves on
the work Viro did last merge window, and sorts out some of the issues
found with that work."
* 'audit' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7475/1: sys_trace: allow all syscall arguments to be updated via ptrace
ARM: 7474/1: get rid of TIF_SYSCALL_RESTARTSYS
ARM: 7473/1: deal with handlerless restarts without leaving the kernel
ARM: 7472/1: pull all work_pending logics into C function
ARM: 7471/1: Revert "7442/1: Revert "remove unused restart trampoline""
ARM: 7470/1: Revert "7443/1: Revert "new way of handling ERESTART_RESTARTBLOCK""
Pull ARM fixes from Russell King:
"This fixes various issues found during July"
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7479/1: mm: avoid NULL dereference when flushing gate_vma with VIVT caches
ARM: Fix undefined instruction exception handling
ARM: 7480/1: only call smp_send_stop() on SMP
ARM: 7478/1: errata: extend workaround for erratum #720789
ARM: 7477/1: vfp: Always save VFP state in vfp_pm_suspend on UP
ARM: 7476/1: vfp: only clear vfp state for current cpu in vfp_pm_suspend
ARM: 7468/1: ftrace: Trace function entry before updating index
ARM: 7467/1: mutex: use generic xchg-based implementation for ARMv6+
ARM: 7466/1: disable interrupt before spinning endlessly
ARM: 7465/1: Handle >4GB memory sizes in device tree and mem=size@start option
While trying to get a v3.5 kernel booted on the cubox, I noticed that
VFP does not work correctly with VFP bounce handling. This is because
of the confusion over 16-bit vs 32-bit instructions, and where PC is
supposed to point to.
The rule is that FP handlers are entered with regs->ARM_pc pointing at
the _next_ instruction to be executed. However, if the exception is
not handled, regs->ARM_pc points at the faulting instruction.
This is easy for ARM mode, because we know that the next instruction and
previous instructions are separated by four bytes. This is not true of
Thumb2 though.
Since all FP instructions are 32-bit in Thumb2, it makes things easy.
We just need to select the appropriate adjustment. Do this by moving
the adjustment out of do_undefinstr() into the assembly code, as only
the assembly code knows whether it's dealing with a 32-bit or 16-bit
instruction.
Cc: <stable@vger.kernel.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 722b3c7469 modified x86 ftrace to
avoid tracing all functions called from irqs when function graph was
used with a filter. Port the same fix to ARM.
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The CPU will endlessly spin at the end of machine_halt and
machine_restart calls. However, this will lead to a soft lockup
warning after about 20 seconds, if CONFIG_LOCKUP_DETECTOR is enabled,
as system timer is still alive.
Disable interrupt before going to spin endlessly, so that the lockup
warning will never be seen.
Cc: <stable@vger.kernel.org>
Reported-by: Marek Vasut <marex@denx.de>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The memory regions which are passed to arm_add_memory() from
device tree blobs via early_init_dt_add_memory_arch() can
have sizes which are larger than will fit in a 32 bit integer,
so switch to using a phys_addr_t to hold them, to avoid
silently dropping the top 32 bits of the size. Similarly, use
phys_addr_t in early_mem() so that mem=size@start command line
options specifying more than 4GB behave sensibly.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Prior to syscall invocation, __sys_trace only reloads r0-r3 from the
kernel stack, preventing the debugger from updating arguments 5-7 when
signalled via ptrace.
This patch updates the code to reload r0-r6, updating arguments 5 and 6
on the stack (argument 7 is only used by OABI indirect syscalls and
can remain in a register).
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
just let do_work_pending() return 1 on normal local restarts and
-1 on those that had been caused by ERESTART_RESTARTBLOCK (and 0
is still "all done, sod off to userland now"). And let the asm
glue flip scno to restart_syscall(2) one if it got negative from
us...
[will: resolved conflicts with audit fixes]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit 3b0c062267.
We no longer require the restart trampoline for syscall restarting.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit 433e2f307b.
Conflicts:
arch/arm/kernel/ptrace.c
Reintroduce the new syscall restart handling in preparation for further
patches from Al Viro.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM updates from Russell King:
"First ARM push of this merge window, post me coming back from holiday.
This is what has been in linux-next for the last few weeks. Not much
to say which isn't described by the commit summaries."
* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (32 commits)
ARM: 7463/1: topology: Update cpu_power according to DT information
ARM: 7462/1: topology: factorize the update of sibling masks
ARM: 7461/1: topology: Add arch_scale_freq_power function
ARM: 7456/1: ptrace: provide separate functions for tracing syscall {entry,exit}
ARM: 7455/1: audit: move syscall auditing until after ptrace SIGTRAP handling
ARM: 7454/1: entry: don't bother with syscall tracing on ret_from_fork path
ARM: 7453/1: audit: only allow syscall auditing for pure EABI userspace
ARM: 7452/1: delay: allow timer-based delay implementation to be selected
ARM: 7451/1: arch timer: implement read_current_timer and get_cycles
ARM: 7450/1: dcache: select DCACHE_WORD_ACCESS for little-endian ARMv6+ CPUs
ARM: 7449/1: use generic strnlen_user and strncpy_from_user functions
ARM: 7448/1: perf: remove arm_perf_pmu_ids global enumeration
ARM: 7447/1: rwlocks: remove unused branch labels from trylock routines
ARM: 7446/1: spinlock: use ticket algorithm for ARMv6+ locking implementation
ARM: 7445/1: mm: update CONTEXTIDR register to contain PID of current process
ARM: 7444/1: kernel: add arch-timer C3STOP feature
ARM: 7460/1: remove asm/locks.h
ARM: 7439/1: head.S: simplify initial page table mapping
ARM: 7437/1: zImage: Allow DTB command line concatenation with ATAG_CMDLINE
ARM: 7436/1: Do not map the vectors page as write-through on UP systems
...
Host bridge hotplug
- Add MMCONFIG support for hot-added host bridges (Jiang Liu)
Device hotplug
- Move fixups from __init to __devinit (Sebastian Andrzej Siewior)
- Call FINAL fixups for hot-added devices, too (Myron Stowe)
- Factor out generic code for P2P bridge hot-add (Yinghai Lu)
- Remove all functions in a slot, not just those with _EJx (Amos Kong)
Dynamic resource management
- Track bus number allocation (struct resource tree per domain) (Yinghai Lu)
- Make P2P bridge 1K I/O windows work with resource reassignment (Bjorn Helgaas, Yinghai Lu)
- Disable decoding while updating 64-bit BARs (Bjorn Helgaas)
Power management
- Add PCIe runtime D3cold support (Huang Ying)
Virtualization
- Add VFIO infrastructure (ACS, DMA source ID quirks) (Alex Williamson)
- Add quirks for devices with broken INTx masking (Jan Kiszka)
Miscellaneous
- Fix some PCI Express capability version issues (Myron Stowe)
- Factor out some arch code with a weak, generic, pcibios_setup() (Myron Stowe)
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Merge tag 'for-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI changes from Bjorn Helgaas:
"Host bridge hotplug:
- Add MMCONFIG support for hot-added host bridges (Jiang Liu)
Device hotplug:
- Move fixups from __init to __devinit (Sebastian Andrzej Siewior)
- Call FINAL fixups for hot-added devices, too (Myron Stowe)
- Factor out generic code for P2P bridge hot-add (Yinghai Lu)
- Remove all functions in a slot, not just those with _EJx (Amos
Kong)
Dynamic resource management:
- Track bus number allocation (struct resource tree per domain)
(Yinghai Lu)
- Make P2P bridge 1K I/O windows work with resource reassignment
(Bjorn Helgaas, Yinghai Lu)
- Disable decoding while updating 64-bit BARs (Bjorn Helgaas)
Power management:
- Add PCIe runtime D3cold support (Huang Ying)
Virtualization:
- Add VFIO infrastructure (ACS, DMA source ID quirks) (Alex
Williamson)
- Add quirks for devices with broken INTx masking (Jan Kiszka)
Miscellaneous:
- Fix some PCI Express capability version issues (Myron Stowe)
- Factor out some arch code with a weak, generic, pcibios_setup()
(Myron Stowe)"
* tag 'for-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (122 commits)
PCI: hotplug: ensure a consistent return value in error case
PCI: fix undefined reference to 'pci_fixup_final_inited'
PCI: build resource code for M68K architecture
PCI: pciehp: remove unused pciehp_get_max_lnk_width(), pciehp_get_cur_lnk_width()
PCI: reorder __pci_assign_resource() (no change)
PCI: fix truncation of resource size to 32 bits
PCI: acpiphp: merge acpiphp_debug and debug
PCI: acpiphp: remove unused res_lock
sparc/PCI: replace pci_cfg_fake_ranges() with pci_read_bridge_bases()
PCI: call final fixups hot-added devices
PCI: move final fixups from __init to __devinit
x86/PCI: move final fixups from __init to __devinit
MIPS/PCI: move final fixups from __init to __devinit
PCI: support sizing P2P bridge I/O windows with 1K granularity
PCI: reimplement P2P bridge 1K I/O windows (Intel P64H2)
PCI: disable MEM decoding while updating 64-bit MEM BARs
PCI: leave MEM and IO decoding disabled during 64-bit BAR sizing, too
PCI: never discard enable/suspend/resume_early/resume fixups
PCI: release temporary reference in __nv_msi_ht_cap_quirk()
PCI: restructure 'pci_do_fixups()'
...
The I.MX platform is getting converted to use sparse IRQs. We are doing
this for all platforms over time, because this is one of the
requirements for building a multiplatform kernel, and generally a good
idea.
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Merge tag 'irq' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull arm-soc sparse IRQ conversion from Arnd Bergmann:
"The I.MX platform is getting converted to use sparse IRQs. We are
doing this for all platforms over time, because this is one of the
requirements for building a multiplatform kernel, and generally a good
idea."
* tag 'irq' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: imx: select USE_OF
ARM: imx: Fix build error due to missing irqs.h include
ARM: imx: enable SPARSE_IRQ for imx platform
ARM: fiq: change FIQ_START to a variable
tty: serial: imx: remove the use of MXC_INTERNAL_IRQS
ARM: imx: remove unneeded mach/irq.h inclusion
i2c: imx: remove unneeded mach/irqs.h inclusion
ARM: imx: add a legacy irqdomain for mx31ads
ARM: imx: add a legacy irqdomain for 3ds_debugboard
ARM: imx: pass gpio than irq number into mxc_expio_init
ARM: imx: leave irq_base of wm8350_platform_data uninitialized
dma: ipu: remove the use of ipu_platform_data
ARM: imx: move irq_domain_add_legacy call into avic driver
ARM: imx: move irq_domain_add_legacy call into tzic driver
gpio/mxc: move irq_domain_add_legacy call into gpio driver
ARM: imx: eliminate macro IRQ_GPIOx()
ARM: imx: eliminate macro IOMUX_TO_IRQ()
ARM: imx: eliminate macro IMX_GPIO_TO_IRQ()
Patches from Alexander Shiyan <shc_work@mail.ru>:
* clps711x/cleanup:
ARM: clps711x: Remove the setting of the time
ARM: clps711x: Removed superfluous transform virt_to_bus and related functions
ARM: clps711x/p720t: Replace __initcall by .init_early call
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Use cpu compatibility field and clock-frequency field of DT to
estimate the capacity of each core of the system and to update
the cpu_power field accordingly.
This patch enables to put more running tasks on big cores than
on LITTLE ones. But this patch doesn't ensure that long running
tasks will run on big cores and short ones on LITTLE cores.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This factorization has also been proposed in another patch that has not been
merged yet:
http://lists.infradead.org/pipermail/linux-arm-kernel/2012-January/080873.html
So, this patch could be dropped depending of the state of the other one.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add infrastructure to be able to modify the cpu_power of each core
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The syscall_trace on ARM takes a `why' parameter to indicate whether or
not we are entering or exiting a system call. This can be confusing for
people looking at the code since (a) it conflicts with the why register
alias in the entry assembly code and (b) it is not immediately clear
what it represents.
This patch splits up the syscall_trace function into separate wrappers
for syscall entry and exit, allowing the low-level syscall handling
code to branch to the appropriate function.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When auditing system calls on ARM, the audit code is called before
notifying the parent process in the case that the current task is being
ptraced. At this point, the parent (debugger) may choose to change the
system call being issued via the SET_SYSCALL ptrace request, causing
the wrong system call to be reported to the audit tools.
This patch moves the audit calls after the ptrace SIGTRAP handling code
in the syscall tracing implementation.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ret_from_fork is setup for a freshly spawned child task via copy_thread,
called from copy_process. The latter function clears TIF_SYSCALL_TRACE
and also resets the child task's audit_context to NULL, meaning that
there is little point invoking the system call tracing routines.
Furthermore, getting hold of the syscall number is a complete pain and
it looks like the current code doesn't even bother.
This patch removes the syscall tracing checks from ret_from_fork.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch allows a timer-based delay implementation to be selected by
switching the delay routines over to use get_cycles, which is
implemented in terms of read_current_timer. This further allows us to
skip the loop calibration and have a consistent delay function in the
face of core frequency scaling.
To avoid the pain of dealing with memory-mapped counters, this
implementation uses the co-processor interface to the architected timers
when they are available. The previous loop-based implementation is
kept around for CPUs without the architected timers and we retain both
the maximum delay (2ms) and the corresponding conversion factors for
determining the number of loops required for a given interval. Since the
indirection of the timer routines will only work when called from C,
the sa1100 sleep routines are modified to branch to the loop-based delay
functions directly.
Tested-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch implements read_current_timer using the architected timers
when they are selected via CONFIG_ARM_ARCH_TIMER. If they are detected
not to be usable at runtime, we return -ENXIO to the caller.
Furthermore, if read_current_timer is exported then we can implement
get_cycles in terms of it for use as both an entropy source and for
implementing __udelay and friends.
Tested-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch implements the word-at-a-time interface for ARM using the
same algorithm as x86. We use the fls macro from ARMv5 onwards, where
we have a clz instruction available which saves us a mov instruction
when targetting Thumb-2. For older CPUs, we use the magic 0x0ff0001
constant. Big-endian configurations make use of the implementation from
asm-generic.
With this implemented, we can replace our byte-at-a-time strnlen_user
and strncpy_from_user functions with the optimised generic versions.
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In order to provide PMU name strings compatible with the OProfile
user ABI, an enumeration of all PMUs is currently used by perf to
identify each PMU uniquely. Unfortunately, this does not scale well
in the presence of multiple PMUs and creates a single, global namespace
across all PMUs in the system.
This patch removes the enumeration and instead uses the name string
for the PMU to map onto the OProfile variant. perf_pmu_name is
implemented for CPU PMUs, which is all that OProfile cares about anyway.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When a CPU is shutdown its architected timer comparators registers are
lost. Within CPU idle, before processors enter shutdown they enter
clock events broadcast mode through the
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, cpuid);
function where the local timers are emulated by a global always-on timer.
On CPU resume, the per-CPU tick device normal mode is restored by exiting
broadcast mode through
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, cpuid);
In order for this mechanism to function, architected timers should add to
their feature C3STOP, which means that they are not able to function when the
CPU is in off-mode.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Let's map the initial RAM up to the end of the kernel .bss instead of
the strict kernel image area. This simplifies the code as the kernel
image only needs to be handled specially in the XIP case. That covers
the legacy ATAG location as well.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Robustify ARM's die() handling with improvements from x86:
- Fix for a deadlock (before panic in the case of panic_on_oops) if we
oops under a spinlock which is also used from interrupt handler,
since the old code was unconditionally enabling interrupts.
- Usage of arch spinlock so lockdep etc doesn't get involved while
we're trying to dump out oopses.
- Deadlock prevention in the unlikely event that die() recurses.
The changes all touch the same few lines of code, so they're done
together in one patch.
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
While running hotplug tests I ran into this RCU splat
===============================
[ INFO: suspicious RCU usage. ]
3.4.0 #3275 Tainted: G W
-------------------------------
include/linux/rcupdate.h:729 rcu_read_lock() used illegally while idle!
other info that might help us debug this:
RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 0
RCU used illegally from extended quiescent state!
4 locks held by swapper/2/0:
#0: ((cpu_died).wait.lock){......}, at: [<c00ab128>] complete+0x1c/0x5c
#1: (&p->pi_lock){-.-.-.}, at: [<c00b275c>] try_to_wake_up+0x2c/0x388
#2: (&rq->lock){-.-.-.}, at: [<c00b2860>] try_to_wake_up+0x130/0x388
#3: (rcu_read_lock){.+.+..}, at: [<c00abe5c>] cpuacct_charge+0x28/0x1f4
stack backtrace:
[<c001521c>] (unwind_backtrace+0x0/0x12c) from [<c00abec8>] (cpuacct_charge+0x94/0x1f4)
[<c00abec8>] (cpuacct_charge+0x94/0x1f4) from [<c00b395c>] (update_curr+0x24c/0x2c8)
[<c00b395c>] (update_curr+0x24c/0x2c8) from [<c00b59c4>] (enqueue_task_fair+0x50/0x194)
[<c00b59c4>] (enqueue_task_fair+0x50/0x194) from [<c00afea4>] (enqueue_task+0x30/0x34)
[<c00afea4>] (enqueue_task+0x30/0x34) from [<c00b0908>] (ttwu_activate+0x14/0x38)
[<c00b0908>] (ttwu_activate+0x14/0x38) from [<c00b28a8>] (try_to_wake_up+0x178/0x388)
[<c00b28a8>] (try_to_wake_up+0x178/0x388) from [<c00a82a0>] (__wake_up_common+0x34/0x78)
[<c00a82a0>] (__wake_up_common+0x34/0x78) from [<c00ab154>] (complete+0x48/0x5c)
[<c00ab154>] (complete+0x48/0x5c) from [<c07db7cc>] (cpu_die+0x2c/0x58)
[<c07db7cc>] (cpu_die+0x2c/0x58) from [<c000f954>] (cpu_idle+0x64/0xfc)
[<c000f954>] (cpu_idle+0x64/0xfc) from [<80208160>] (0x80208160)
When a cpu is marked offline during its idle thread it calls
cpu_die() during an RCU idle period. cpu_die() calls complete()
to notify the killing process that the cpu has died. complete()
calls into the scheduler code and eventually grabs an RCU read
lock in cpuacct_charge().
Mark complete() as RCU_NONIDLE so that RCU pays attention to this
CPU for the duration of the complete() function even though it's
in idle.
Suggested-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
'sub pc, pc, #1b-2b+8-2' results in address<1:0> == '10'.
sub pc, pc, #const (== ADR pc, #const) performs an interworking branch
(BXWritePC()) on ARMv7+ and a simple branch (BranchWritePC()) on earlier
versions.
In ARM state, BXWritePC() is UNPREDICTABLE when address<1:0> == '10'.
In ARM state on ARMv6+, BranchWritePC() ignores address<1:0>. Before
ARMv6, BranchWritePC() is UNPREDICTABLE if address<1:0> != '00'
So the instruction is UNPREDICTABLE both before and after v6.
Acked-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We currently return -EPERM if the user requests mode exclusion that is
not supported by the CPU. This looks pretty confusing from userspace
and is inconsistent with other architectures (ppc, x86).
This patch returns -EOPNOTSUPP instead.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit 6b5c8045ec.
Conflicts:
arch/arm/kernel/ptrace.c
The new syscall restarting code can lead to problems if we take an
interrupt in userspace just before restarting the svc instruction. If
a signal is delivered when returning from the interrupt, the
TIF_SYSCALL_RESTARTSYS will remain set and cause any syscalls executed
from the signal handler to be treated as a restart of the previously
interrupted system call. This includes the final sigreturn call, meaning
that we may fail to exit from the signal context. Furthermore, if a
system call made from the signal handler requires a restart via the
restart_block, it is possible to clear the thread flag and fail to
restart the originally interrupted system call.
The right solution to this problem is to perform the restarting in the
kernel, avoiding the possibility of handling a further signal before the
restart is complete. Since we're almost at -rc6, let's revert the new
method for now and aim for in-kernel restarting at a later date.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit fa18484d09.
We need the restart trampoline back so that we can revert a related
problematic patch 6b5c8045ec ("arm: new
way of handling ERESTART_RESTARTBLOCK").
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
From Shawn Guo <shawn.guo@linaro.org>, this makes it possible to use
sparse irqs with mach-imx.
* 'imx/sparse-irq' of git://git.linaro.org/people/shawnguo/linux-2.6:
ARM: imx: enable SPARSE_IRQ for imx platform
ARM: fiq: change FIQ_START to a variable
tty: serial: imx: remove the use of MXC_INTERNAL_IRQS
ARM: imx: remove unneeded mach/irq.h inclusion
i2c: imx: remove unneeded mach/irqs.h inclusion
ARM: imx: add a legacy irqdomain for mx31ads
ARM: imx: add a legacy irqdomain for 3ds_debugboard
ARM: imx: pass gpio than irq number into mxc_expio_init
ARM: imx: leave irq_base of wm8350_platform_data uninitialized
dma: ipu: remove the use of ipu_platform_data
ARM: imx: move irq_domain_add_legacy call into avic driver
ARM: imx: move irq_domain_add_legacy call into tzic driver
gpio/mxc: move irq_domain_add_legacy call into gpio driver
ARM: imx: eliminate macro IRQ_GPIOx()
ARM: imx: eliminate macro IOMUX_TO_IRQ()
ARM: imx: eliminate macro IMX_GPIO_TO_IRQ()
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The Advanced Interrupt Controller allows us to use the fast EOI handler type.
It lets us remove the Atmel specific workaround into arch/arm/kernel/irq.c
used to indicate to the AIC the end of the interrupt treatment.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The commit a2be01b (ARM: only include mach/irqs.h for !SPARSE_IRQ)
makes mach/irqs.h only be included for !SPARSE_IRQ build. There are
a nubmer of platforms have FIQ_START defined in mach/irqs.h for FIQ
support.
arch/arm/mach-rpc/include/mach/irqs.h:#define FIQ_START 64
arch/arm/mach-s3c24xx/include/mach/irqs.h:#define FIQ_START IRQ_EINT0
arch/arm/plat-mxc/include/mach/irqs.h:#define FIQ_START 0
If SPARSE_IRQ is enabled for any of these platforms, the following
compile error will be seen.
arch/arm/kernel/fiq.c: In function ‘enable_fiq’:
arch/arm/kernel/fiq.c:127:19: error: ‘FIQ_START’ undeclared (first use in this function)
arch/arm/kernel/fiq.c:127:19: note: each undeclared identifier is reported only once for each function it appears in
arch/arm/kernel/fiq.c: In function ‘disable_fiq’:
arch/arm/kernel/fiq.c:132:20: error: ‘FIQ_START’ undeclared (first use in this function)
The patch changes fiq code to have init_FIQ take FIQ_START from
platforms as a parameter and assign it to variable fiq_start which
is to replace FIQ_START uses in enable_fiq/disable_fiq.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM builds seem to be plagued by an occasional build error:
Inconsistent kallsyms data
This is a bug - please report about it
Try "make KALLSYMS_EXTRA_PASS=1" as a workaround
The problem has to do with alignment of some sections by the linker.
The kallsyms data is built in two passes by first linking the kernel
without it, and then linking the kernel again with the symbols
included. Normally, this just shifts the symbols, without changing
their order, and the compression used by the kallsyms gives the same
result.
On non SMP, the per CPU data is empty. Depending on the where the
alignment ends up, it can come out as either:
+-------------------+
| last text segment |
+-------------------+
/* padding */
+-------------------+ <- L1_CACHE_BYTES alignemnt
| per cpu (empty) |
+-------------------+
__per_cpu_end:
/* padding */
__data_loc:
+-------------------+ <- THREAD_SIZE alignment
| data |
+-------------------+
or
+-------------------+
| last text segment |
+-------------------+
/* padding */
+-------------------+ <- L1_CACHE_BYTES alignemnt
| per cpu (empty) |
+-------------------+
__per_cpu_end:
/* no padding */
__data_loc:
+-------------------+ <- THREAD_SIZE alignment
| data |
+-------------------+
if the alignment satisfies both. Because symbols that have the same
address are sorted by 'nm -n', the second case will be in a different
order than the first case. This changes the compression, changing the
size of the kallsym data, causing the build failure.
The KALLSYMS_EXTRA_PASS=1 workaround usually works, but it is still
possible to have the alignment change between the second and third
pass. It's probably even possible for it to never reach a fixedpoint.
The problem only occurs on non-SMP, when the per-cpu data is empty,
and when the data segment has alignment (and immediately follows the
text segments). Fix this by only including the per_cpu section on
SMP, when it is not empty.
Signed-off-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* topic/sebastian-devinit-fixups:
scripts/modpost: check for bad references in .pci.fixups area
sh/PCI: move fixup hooks from __init to __devinit
powerpc/PCI: move fixup hooks from __init to __devinit
frv/PCI: move fixup hooks from __init to __devinit
arm/PCI: move fixup hooks from __init to __devinit
alpha/PCI: move fixup hooks from __init to __devinit
PCI: move fixup hooks from __init to __devinit
x86/PCI: move fixup hooks from __init to __devinit
Fixup entries in the kernel exception tables should be 4-byte aligned
since we return directly to them when handling a faulting instruction in
the kernel.
This patch adds the missing align directives to the fixup entries.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
t32_simulate_ldr_literal() can be run without an instruction slot, so it
should be using DECODE_SIMULATEX instead of DECODE_EMULATEX.
Acked-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Replace the struct pci_bus secondary/subordinate members with the
struct resource busn_res. Later we'll build a resource tree of these
bus numbers.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The fixups are executed once the pci-device is found which is during
boot process so __init seems fine as long as the platform does not
support hotplug.
However it is possible to remove the PCI bus at run time and have it
rediscovered again via "echo 1 > /sys/bus/pci/rescan" and this will call
the fixups again.
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Does block_sigmask() + tracehook_signal_handler(); called when
sigframe has been successfully built. All architectures converted
to it; block_sigmask() itself is gone now (merged into this one).
I'm still not too happy with the signature, but that's a separate
story (IMO we need a structure that would contain signal number +
siginfo + k_sigaction, so that get_signal_to_deliver() would fill one,
signal_delivered(), handle_signal() and probably setup...frame() -
take one).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Marc Zyngier