History log of /arch/arm/kernel/process.c
Revision Date Author Comments
e5105fc84f84308f8aa0dac4ce969d40a1aaea2d 25-May-2012 Mike J. Chen <mjchen@google.com> ARM: disable preemption in machine_shutdown

Since the smp call to stop the other cpus are handled in those
cpus in interrupt context, there's a potential for those smp
handlers to interrupt threads holding spin locks (such as the
one a mutex holds). This prevents those threads from ever
releasing their spin lock, so if the cpu doing the shutdown
is allowed to switch to another thread that tries to grab the
same lock/mutex, we could get into a deadlock (the spin lock
call is called with preemption disabled in the mutex lock code).

To avoid that possibility, disable preemption before doing the
smp_send_stop().

Change-Id: I7976c5382d7173fcb3cd14da8cc5083d442b2544
Signed-off-by: Mike J. Chen <mjchen@google.com>
6b7343ff1f3fb25da5aff83053c573f16b36cf1c 16-Jun-2011 Todd Poynor <toddpoynor@google.com> ARM: Call idle notifiers

Change-Id: Id833e61c13baa1783705ac9e9046d1f0cc90c95e
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
2cc932a48acafb426d10671af734f68246a7bf9b 24-Aug-2011 Dima Zavin <dima@android.com> ARM: add option to flush console before reboot

If the console_lock was held while the system was rebooted, the messages
in the temporary logbuffer would not have propogated to all the console
drivers.

This force releases the console lock if it failed to be acquired.

Change-Id: I193dcf7b968be17966833e50b8b8bc70d5d9fe89
Signed-off-by: Dima Zavin <dima@android.com>
d4dcc857a55bb7d6ac57d7a2e9ecd31d8d68f41a 19-Oct-2011 Dima Zavin <dima@android.com> ARM: smp: implement arch_trigger_all_cpus_backtrace using IPI

Based on a rough patch by frank.rowand@am.sony.com

Since ARM doesn't have an NMI (fiq's are not always available),
send an IPI to all other CPUs (current cpu prints the stack directly)
to capture a backtrace.

Change-Id: I8b163c8cec05d521b433ae133795865e8a33d4e2
Signed-off-by: Dima Zavin <dima@android.com>
ac2054661f4ebd721642feb9227d2d84afe3b887 26-Aug-2009 San Mehat <san@google.com> [ARM] process: Add display of memory around registers when displaying regs.

This is extremely useful in diagnosing remote crashes, and is based heavily
on original work by <md@google.com>.

Signed-off-by: San Mehat <san@google.com>
Cc: Michael Davidson <md@google.com>

[ARM] process: Use uber-safe probe_kernel_address() to read mem when dumping.

This prevents the dump from taking pagefaults / external aborts.

Signed-off-by: San Mehat <san@google.com>
389522b0c0530658eb9f9a53410ec2494616d785 22-Sep-2014 Nathan Lynch <nathan_lynch@mentor.com> ARM: 8155/1: place sigpage at a random offset above stack

The sigpage is currently placed alongside shared libraries etc in the
address space. Similar to what x86_64 does for its VDSO, place the
sigpage at a randomized offset above the stack so that learning the
base address of the sigpage doesn't help expose where shared libraries
are loaded in the address space (and vice versa).

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
02e0409a65560da66a747d2ac6023715b04659ea 22-Sep-2014 Nathan Lynch <nathan_lynch@mentor.com> ARM: 8154/1: use _install_special_mapping for sigpage

_install_special_mapping allows the VMA to be identifed in
/proc/pid/maps without the use of arch_vma_name, providing a
slight net reduction in object size:

text data bss dec hex filename
2996 96 144 3236 ca4 arch/arm/kernel/process.o (before)
2956 104 144 3204 c84 arch/arm/kernel/process.o (after)

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
6cd6d94d96d9b1cd8a62da91aac44cf56e301e75 26-Sep-2014 Guenter Roeck <linux@roeck-us.net> arm/arm64: unexport restart handlers

Implementing a restart handler in a module don't make sense as there would
be no guarantee that the module is loaded when a restart is needed.
Unexport arm_pm_restart to ensure that no one gets the idea to do it
anyway.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonas Jensen <jonas.jensen@gmail.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
1a9607a3be14a43868c5e6a35962e7f6be9bcfe1 26-Sep-2014 Guenter Roeck <linux@roeck-us.net> arm: support restart through restart handler call chain

The kernel core now supports a restart handler call chain for system
restart functions.

With this change, the arm_pm_restart callback is now optional, so drop its
initialization and check if it is set before calling it. Only call the
kernel restart handler if arm_pm_restart is not set.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonas Jensen <jonas.jensen@gmail.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
7f038073c0a3e22e12344ab8b41d46547c072c82 04-Sep-2014 Russell King <rmk+kernel@arm.linux.org.uk> ARM: remove extraneous newline in show_regs()

Remove an unnecessary newline in show_regs().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
fbfb872f5f417cea48760c535e0ff027c88b507a 11-Sep-2014 Nathan Lynch <nathan_lynch@mentor.com> ARM: 8148/1: flush TLS and thumbee register state during exec

The TPIDRURO and TPIDRURW registers need to be flushed during exec;
otherwise TLS information is potentially leaked. TPIDRURO in
particular needs careful treatment. Since flush_thread basically
needs the same code used to set the TLS in arm_syscall, pull that into
a common set_tls helper in tls.h and use it in both places.

Similarly, TEEHBR needs to be cleared during exec as well. Clearing
its save slot in thread_info isn't right as there is no guarantee
that a thread switch will occur before the new program runs. Just
setting the register directly is sufficient.

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
779dd9590b00bd91b7811c24f0df34a9d91bfa0f 06-Apr-2014 Russell King <rmk+kernel@arm.linux.org.uk> ARM: add missing system_misc.h include to process.c

arm_pm_restart(), arm_pm_idle() and soft_restart() are all declared in
system_misc.h, but this file is not included in process.c. Add this
missing include. Found via sparse:

arch/arm/kernel/process.c:98:6: warning: symbol 'soft_restart' was not declared. Should it be static?
arch/arm/kernel/process.c:127:6: warning: symbol 'arm_pm_restart' was not declared. Should it be static?
arch/arm/kernel/process.c:134:6: warning: symbol 'arm_pm_idle' was not declared. Should it be static?

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
c7d442f46c1bb18e48204f41c3d838c475eb5130 25-Mar-2014 Sebastian Capella <sebastian.capella@linaro.org> ARM: 8010/1: avoid tracers in soft_restart

Use of tracers in local_irq_disable is causes abort loops when called
with irqs disabled using a temporary stack. Replace local_irq_disable
with raw_local_irq_disable instead to avoid tracers.

Signed-off-by: Sebastian Capella <sebastian.capella@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ad68cc7a777948b77f15a3dc3510918ff87ed0c0 29-Jan-2014 Nicolas Pitre <nicolas.pitre@linaro.org> sched/idle, ARM: Remove redundant cpuidle_idle_call()

The core idle loop now takes care of it.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-sh@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linaro-kernel@lists.linaro.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-y2nbw5j3ma5siy5584919z5i@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
e2e55fde3f2eaeb1d341508108a51a61dd0fb470 16-Dec-2013 Uwe Kleine-König <u.kleine-koenig@pengutronix.de> ARM: show_regs: on v7-M there are no FIQs, different processor modes, ...

no indication about irqs in PSR and only a single ISA. So skip the whole
decoding and just print the xPSR on v7-M.

Also mark two static variables as __maybe_unused to prevent the compiler
from emitting:

arch/arm/kernel/process.c:51:20: warning: 'processor_modes' defined but not used [-Wunused-variable]
arch/arm/kernel/process.c:58:20: warning: 'isa_modes' defined but not used [-Wunused-variable]

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
1b15ec7a7427d4188ba91b9bbac696250a059d22 05-Dec-2013 Konstantin Khlebnikov <k.khlebnikov@samsung.com> ARM: 7912/1: check stack pointer in get_wchan

get_wchan() is lockless. Task may wakeup at any time and change its own stack,
thus each next stack frame may be overwritten and filled with random stuff.

/proc/$pid/stack interface had been disabled for non-current tasks, see [1]
But 'wchan' still allows to trigger stack frame unwinding on volatile stack.

This patch fixes oops in unwind_frame() by adding stack pointer validation on
each step (as x86 code do), unwind_frame() already checks frame pointer.

Also I've found another report of this oops on stackoverflow (irony).

Link: http://www.spinics.net/lists/arm-kernel/msg110589.html [1]
Link: http://stackoverflow.com/questions/18479894/unwind-frame-cause-a-kernel-paging-error

Cc: <stable@vger.kernel.org>
Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
1d0bbf428924f94867542d49d436cf254b9dbd06 06-Aug-2013 Russell King <rmk+kernel@arm.linux.org.uk> ARM: Fix the world famous typo with is_gate_vma()

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
e0d407564b532d978b03ceccebd224a05d02f111 03-Aug-2013 Russell King <rmk+kernel@arm.linux.org.uk> ARM: fix a cockup in 48be69a02 (ARM: move signal handlers into a vdso-like page)

Unfortunately, I never committed the fix to a nasty oops which can
occur as a result of that commit:

------------[ cut here ]------------
kernel BUG at /home/olof/work/batch/include/linux/mm.h:414!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 490 Comm: killall5 Not tainted 3.11.0-rc3-00288-gabe0308 #53
task: e90acac0 ti: e9be8000 task.ti: e9be8000
PC is at special_mapping_fault+0xa4/0xc4
LR is at __do_fault+0x68/0x48c

This doesn't show up unless you do quite a bit of testing; a simple
boot test does not do this, so all my nightly tests were passing fine.

The reason for this is that install_special_mapping() expects the
page array to stick around, and as this was only inserting one page
which was stored on the kernel stack, that's why this was blowing up.

Reported-by: Olof Johansson <olof@lixom.net>
Tested-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
44424c34049f41123a3a8b4853822f47f4ff03a2 31-Jul-2013 Stephen Boyd <sboyd@codeaurora.org> ARM: 7803/1: Fix deadlock scenario with smp_send_stop()

If one process calls sys_reboot and that process then stops other
CPUs while those CPUs are within a spin_lock() region we can
potentially encounter a deadlock scenario like below.

CPU 0 CPU 1
----- -----
spin_lock(my_lock)
smp_send_stop()
<send IPI> handle_IPI()
disable_preemption/irqs
while(1);
<PREEMPT>
spin_lock(my_lock) <--- Waits forever

We shouldn't attempt to run any other tasks after we send a stop
IPI to a CPU so disable preemption so that this task runs to
completion. We use local_irq_disable() here for cross-arch
consistency with x86.

Reported-by: Sundarajan Srinivasan <sundaraj@codeaurora.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
a5463cd3435475386cbbe7b06e01292ac169d36f 31-Jul-2013 Russell King <rmk+kernel@arm.linux.org.uk> ARM: make vectors page inaccessible from userspace

If kuser helpers are not provided by the kernel, disable user access to
the vectors page. With the kuser helpers gone, there is no reason for
this page to be visible to userspace.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
48be69a026b2c17350a5ef18a1959a919f60be7d 24-Jul-2013 Russell King <rmk+kernel@arm.linux.org.uk> ARM: move signal handlers into a vdso-like page

Move the signal handlers into a VDSO page rather than keeping them in
the vectors page. This allows us to place them randomly within this
page, and also map the page at a random location within userspace
further protecting these code fragments from ROP attacks. The new
VDSO page is also poisoned in the same way as the vector page.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
1b3a5d02ee070c8f9943333b9b6370f486601e0f 09-Jul-2013 Robin Holt <holt@sgi.com> reboot: move arch/x86 reboot= handling to generic kernel

Merge together the unicore32, arm, and x86 reboot= command line
parameter handling.

Signed-off-by: Robin Holt <holt@sgi.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Russ Anderson <rja@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
7b6d864b48d95e6ea1df7df64475b9cb9616dcf9 09-Jul-2013 Robin Holt <holt@sgi.com> reboot: arm: change reboot_mode to use enum reboot_mode

Preparing to move the parsing of reboot= to generic kernel code forces
the change in reboot_mode handling to use the enum.

[akpm@linux-foundation.org: fix arch/arm/mach-socfpga/socfpga.c]
Signed-off-by: Robin Holt <holt@sgi.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Russ Anderson <rja@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
16d6d5b00ee75307bab7e4ede9452c97b28f30e2 09-Jul-2013 Robin Holt <holt@sgi.com> reboot: arm: prepare reboot_mode for moving to generic kernel code

Prepare for the moving the parsing of reboot= to the generic kernel code
by making reboot_mode into a more generic form.

Signed-off-by: Robin Holt <holt@sgi.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Russ Anderson <rja@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
a4780adeefd042482f624f5e0d577bf9cdcbb760 19-Jun-2013 André Hentschel <nerv@dawncrow.de> ARM: 7735/2: Preserve the user r/w register TPIDRURW on context switch and fork

Since commit 6a1c53124aa1 the user writeable TLS register was zeroed to
prevent it from being used as a covert channel between two tasks.

There are more and more applications coming to Windows RT,
Wine could support them, but mostly they expect to have
the thread environment block (TEB) in TPIDRURW.

This patch preserves that register per thread instead of clearing it.
Unlike the TPIDRURO, which is already switched, the TPIDRURW
can be updated from userspace so needs careful treatment in the case that we
modify TPIDRURW and call fork(). To avoid this we must always read
TPIDRURW in copy_thread.

Signed-off-by: André Hentschel <nerv@dawncrow.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
19ab428f4b7988ef3ac727c680efc193ef53ce14 14-Jun-2013 Stephen Warren <swarren@nvidia.com> ARM: 7759/1: decouple CPU offlining from reboot/shutdown

Add comments to machine_shutdown()/halt()/power_off()/restart() that
describe their purpose and/or requirements re: CPUs being active/not.

In machine_shutdown(), replace the call to smp_send_stop() with a call to
disable_nonboot_cpus(). This completely disables all but one CPU, thus
satisfying the requirement that only a single CPU be active for kexec.
Adjust Kconfig dependencies for this change.

In machine_halt()/power_off()/restart(), call smp_send_stop() directly,
rather than via machine_shutdown(); these functions don't need to
completely de-activate all CPUs using hotplug, but rather just quiesce
them.

Remove smp_kill_cpus(), and its call from smp_send_stop().
smp_kill_cpus() was indirectly calling smp_ops.cpu_kill() without calling
smp_ops.cpu_die() on the target CPUs first. At least some implementations
of smp_ops had issues with this; it caused cpu_kill() to hang on Tegra,
for example. Since smp_send_stop() is only used for shutdown, halt, and
power-off, there is no need to attempt any kind of CPU hotplug here.

Adjust Kconfig to reflect that machine_shutdown() (and hence kexec)
relies upon disable_nonboot_cpus(). However, this alone doesn't guarantee
that hotplug will work, or even that hotplug is implemented for a
particular piece of HW that a multi-platform zImage runs on. Hence, add
error-checking to machine_kexec() to determine whether it did work.

Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Zhangfei Gao <zhangfei.gao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
4ca46c5e1f38e32c90247686e9e17dae213ecbdb 16-May-2013 Steven Capper <steve.capper@linaro.org> ARM: 7727/1: remove the .vm_mm value from gate_vma

If one reads /proc/$PID/smaps, the mmap_sem belonging to the
address space of the task being examined is locked for reading.
All the pages of the vmas belonging to the task's address space
are then walked with this lock held.

If a gate_vma is present in the architecture, it too is examined
by the fs/proc/task_mmu.c code. As gate_vma doesn't belong to the
address space of the task though, its pages are not walked.

A recent cleanup (commit f6604efe) of the gate_vma initialisation
code set the vm_mm value to &init_mm. Unfortunately a non-NULL
vm_mm value in the gate_vma will cause the task_mmu code to attempt
to walk the pages of the gate_vma (with no mmap-sem lock held). If
one enables Transparent Huge Page support and vm debugging, this
will then cause OOPses as pmd_trans_huge_lock is called without
mmap_sem being locked.

This patch removes the .vm_mm value from gate_vma, restoring the
original behaviour of the task_mmu code.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
a43cb95d547a061ed5bf1acb28e0f5fd575e26c1 01-May-2013 Tejun Heo <tj@kernel.org> dump_stack: unify debug information printed by show_regs()

show_regs() is inherently arch-dependent but it does make sense to print
generic debug information and some archs already do albeit in slightly
different forms. This patch introduces a generic function to print debug
information from show_regs() so that different archs print out the same
information and it's much easier to modify what's printed.

show_regs_print_info() prints out the same debug info as dump_stack()
does plus task and thread_info pointers.

* Archs which didn't print debug info now do.

alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r,
metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc,
um, xtensa

* Already prints debug info. Replaced with show_regs_print_info().
The printed information is superset of what used to be there.

arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86

* s390 is special in that it used to print arch-specific information
along with generic debug info. Heiko and Martin think that the
arch-specific extra isn't worth keeping s390 specfic implementation.
Converted to use the generic version.

Note that now all archs print the debug info before actual register
dumps.

An example BUG() dump follows.

kernel BUG at /work/os/work/kernel/workqueue.c:4841!
invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7
Hardware name: empty empty/S3992, BIOS 080011 10/26/2007
task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000
RIP: 0010:[<ffffffff8234a07e>] [<ffffffff8234a07e>] init_workqueues+0x4/0x6
RSP: 0000:ffff88007c861ec8 EFLAGS: 00010246
RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001
RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a
RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650
0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d
ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760
Call Trace:
[<ffffffff81000312>] do_one_initcall+0x122/0x170
[<ffffffff82335e5d>] kernel_init_freeable+0x9b/0x1c8
[<ffffffff81c47760>] ? rest_init+0x140/0x140
[<ffffffff81c4776e>] kernel_init+0xe/0xf0
[<ffffffff81c6be9c>] ret_from_fork+0x7c/0xb0
[<ffffffff81c47760>] ? rest_init+0x140/0x140
...

v2: Typo fix in x86-32.

v3: CPU number dropped from show_regs_print_info() as
dump_stack_print_info() has been updated to print it. s390
specific implementation dropped as requested by s390 maintainers.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Chris Metcalf <cmetcalf@tilera.com> [tile bits]
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon bits]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
f7b861b7a6d9d1838cbbb5f4053e61578b86d134 21-Mar-2013 Thomas Gleixner <tglx@linutronix.de> arm: Use generic idle loop

Use the generic idle loop and replace enable/disable_hlt with the
respective core functions.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Tested-by: Kevin Hilman <khilman@linaro.org> # OMAP
Link: http://lkml.kernel.org/r/20130321215233.826238797@linutronix.de
6546327ad187238ac63d2429701b32becb096fd8 21-Mar-2013 Thomas Gleixner <tglx@linutronix.de> arch: Cleanup enable/disable_hlt

enable/disable_hlt() does not need to be exported and can be killed on
architectures which do not use it at all.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Link: http://lkml.kernel.org/r/20130321215233.377959540@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
80bbe9f273a38f83ecfc50fe384a57f8428887bd 06-Mar-2013 Thomas Gleixner <tglx@linutronix.de> arm: Use tick broadcast expired check

Avoid going back into deep idle if the tick broadcast IPI is about to
fire.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: LAK <linux-arm-kernel@lists.infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Arjan van de Veen <arjan@infradead.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Jason Liu <liu.h.jason@gmail.com>
Link: http://lkml.kernel.org/r/20130306111537.640722922@linutronix.de
f6604efe0bee759f4db34757f2872b611288ef0f 23-Feb-2013 Russell King <rmk+kernel@arm.linux.org.uk> ARM: cleanup gate_vma initialization

Three's no need to have code initializing this by hand; it's more
efficient to initialize the constant structure members directly.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
b0ea11497c8cbc5a66019814efa1733e47e47ab1 10-Feb-2013 Len Brown <len.brown@intel.com> ARM idle: delete pm_idle

pm_idle() on ARM was a synonym for default_idle(),
so simply invoke default_idle() directly.

Signed-off-by: Len Brown <len.brown@intel.com>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
afa86fc426ff7e7f5477f15da9c405d08d5cf790 23-Oct-2012 Al Viro <viro@zeniv.linux.org.uk> flagday: don't pass regs to copy_thread()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
38a61b6b4a45ec8c82c75403848e1c579113c3c5 21-Oct-2012 Al Viro <viro@zeniv.linux.org.uk> arm: switch to generic fork/vfork/clone

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
9ecb47de3490b8f2d4b818568935da9ca2c22398 08-Nov-2012 Nicolas Pitre <nicolas.pitre@linaro.org> ARM: 7574/1: kernel/process.c: include idmap.h instead of redeclaring setup_mm_for_reboot()

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
871df85a592396b36d4c40b3860e8d7373626552 29-Sep-2012 fwu <fwu@marvell.com> ARM: 7544/1: Add BUG_ON when hlt counter is wrongly used

1. On ARM platform, "nohlt" can be used to prevent core from idle
process, returning immediately.
2. There are two interfaces, exported for other modules, named
"disable_hlt" and "enable_hlt" are used to enable/disable the
cpuidle mechanism by increasing/decreasing "hlt_counter".
Disable_hlt and enable_hlt are paired operation,
when you first call disable_hlt and then enable_hlt, the
semantics are right.
3. There is no obvious constraint to prevent user(driver/module)
code to prevent the case that enable_hlt is ahead of disable_hlt,
which is a fatal operation on kernel state change from user,
and there is no any WARNING or notification if the case happens
in current kernel code.
This patch aims to report BUG when the case happens, just like
what the kernel do when enable_irq is ahead of disable_irq.

Link: https://patchwork.kernel.org/patch/1527881/

Signed-off-by: fwu <fwu@marvell.com>
Signed-off-by: YiLu Mao <ylmao@marvell.com>
Signed-off-by: Ning Jiang <ning.jiang@marvell.com>
Acked-by: Nicolas Pitre
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
9fff2fa0db911b0b75ec1f9bec72460c0a676ef5 11-Oct-2012 Al Viro <viro@zeniv.linux.org.uk> arm: switch to saner kernel_execve() semantics

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
9e14f828ee4a7a4a98703e380d180717a579fb35 10-Sep-2012 Al Viro <viro@zeniv.linux.org.uk> arm: split ret_from_fork, simplify kernel_thread() [based on patch by rmk]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
fa8bbb13ab49e77c00fa09e5504ec25b7176fb4b 13-Mar-2012 Bryan Wu <bryan.wu@canonical.com> ARM: use new LEDS CPU trigger stub to replace old one

Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
98bd8b96b26db3399a48202318dca4aaa2515355 13-Jul-2012 Shawn Guo <shawn.guo@linaro.org> ARM: 7466/1: disable interrupt before spinning endlessly

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>
448eca90932d97856b6a6097fc50eef96d77dec0 07-May-2012 Thomas Gleixner <tglx@linutronix.de> arm: Remove unused cpu_idle_wait()

cpuidle uses a generic function now. Remove the unused code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/20120507175652.260797846@linutronix.de
9f97da78bf018206fb623cd351d454af2f105fe0 28-Mar-2012 David Howells <dhowells@redhat.com> Disintegrate asm/system.h for ARM

Disintegrate asm/system.h for ARM.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Russell King <linux@arm.linux.org.uk>
cc: linux-arm-kernel@lists.infradead.org
f9d4861fc32b995b1616775614459b8f266c803c 20-Jan-2012 Will Deacon <will.deacon@arm.com> ARM: 7294/1: vectors: use gate_vma for vectors user mapping

The current user mapping for the vectors page is inserted as a `horrible
hack vma' into each task via arch_setup_additional_pages. This causes
problems with the MM subsystem and vm_normal_page, as described here:

https://lkml.org/lkml/2012/1/14/55

Following the suggestion from Hugh in the above thread, this patch uses
the gate_vma for the vectors user mapping, therefore consolidating
the horrible hack VMAs into one.

Acked-and-Tested-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>
909af768e88867016f427264ae39d27a57b6a8ed 23-Mar-2012 Jason Baron <jbaron@redhat.com> coredump: remove VM_ALWAYSDUMP flag

The motivation for this patchset was that I was looking at a way for a
qemu-kvm process, to exclude the guest memory from its core dump, which
can be quite large. There are already a number of filter flags in
/proc/<pid>/coredump_filter, however, these allow one to specify 'types'
of kernel memory, not specific address ranges (which is needed in this
case).

Since there are no more vma flags available, the first patch eliminates
the need for the 'VM_ALWAYSDUMP' flag. The flag is used internally by
the kernel to mark vdso and vsyscall pages. However, it is simple
enough to check if a vma covers a vdso or vsyscall page without the need
for this flag.

The second patch then replaces the 'VM_ALWAYSDUMP' flag with a new
'VM_NODUMP' flag, which can be set by userspace using new madvise flags:
'MADV_DONTDUMP', and unset via 'MADV_DODUMP'. The core dump filters
continue to work the same as before unless 'MADV_DONTDUMP' is set on the
region.

The qemu code which implements this features is at:

http://people.redhat.com/~jbaron/qemu-dump/qemu-dump.patch

In my testing the qemu core dump shrunk from 383MB -> 13MB with this
patch.

I also believe that the 'MADV_DONTDUMP' flag might be useful for
security sensitive apps, which might want to select which areas are
dumped.

This patch:

The VM_ALWAYSDUMP flag is currently used by the coredump code to
indicate that a vma is part of a vsyscall or vdso section. However, we
can determine if a vma is in one these sections by checking it against
the gate_vma and checking for a non-NULL return value from
arch_vma_name(). Thus, freeing a valuable vma bit.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Acked-by: Roland McGrath <roland@hack.frob.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
bd2f55361f18347e890d52ff9cfd8895455ec11b 21-Mar-2011 Thomas Gleixner <tglx@linutronix.de> sched/rt: Use schedule_preempt_disabled()

Coccinelle based conversion.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-24swm5zut3h9c4a6s46x8rws@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
ae940913030386884f259eb4d95ac4d93b57144f 19-Dec-2011 Nicolas Pitre <nicolas.pitre@linaro.org> ARM: substitute arch_idle()

Now that all implementations of arch_idle() are equivalent to cpu_do_idle()
we can just use the later directly and stop including mach/system.h.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-and-tested-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
4fa20439a80c008d33f2865b0db94dcb5da467e2 01-Aug-2011 Nicolas Pitre <nicolas.pitre@linaro.org> ARM: clean up idle handlers

Let's factor out the need_resched() check instead of having it duplicated
in every pm_idle implementations to avoid inconsistencies (omap2_pm_idle
is missing it already).

The forceful re-enablement of IRQs after pm_idle has returned can go.
The warning certainly doesn't trigger for existing users.

To get rid of the pm_idle calling convention oddity, let's introduce
arm_pm_idle() allowing for the local_irq_enable() to be factored out
from SOC specific implementations. The default pm_idle function becomes
a wrapper for arm_pm_idle and it takes care of enabling IRQs closer to
where they are initially disabled.

And finally move the comment explaining the reason for that turning off
of IRQs to a more proper location.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-and-tested-by: Jamie Iles <jamie@jamieiles.com>
f88b8979d26615ce68772cebc85c3b556571afca 05-Nov-2011 Russell King <rmk+kernel@arm.linux.org.uk> ARM: restart: remove the now empty arch_reset()

Remove the now empty arch_reset() from all the mach/system.h includes,
and remove its callsite. Remove arm_machine_restart() as this function
no longer does anything useful.

For samsung platforms, remove the include of mach/system-reset.h and
plat/system-reset.h from their respective mach/system.h headers as these
just define their arch_reset functions. As a result, the s3c2410 and
plat-samsung system-reset.h files are no longer referenced, so remove
these files entirely.

Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
290130a17718c1451bb8a77a5e2510e0279bd5f3 06-Jun-2011 Will Deacon <will.deacon@arm.com> ARM: reset: implement soft_restart for jumping to a physical address

Tools such as kexec and CPU hotplug require a way to reset the processor
and branch to some code in physical space. This requires various bits of
jiggery pokery with the caches and MMU which, when it goes wrong, tends
to lock up the system.

This patch fleshes out the soft_restart implementation so that it
branches to the reset code using the identity mapping. This requires us
to change to a temporary stack, held within the kernel image as a static
array, to avoid conflicting with the new view of memory.

Signed-off-by: Will Deacon <will.deacon@arm.com>
1268fbc746ea1cd279886a740dcbad4ba5232225 17-Nov-2011 Frederic Weisbecker <fweisbec@gmail.com> nohz: Remove tick_nohz_idle_enter_norcu() / tick_nohz_idle_exit_norcu()

Those two APIs were provided to optimize the calls of
tick_nohz_idle_enter() and rcu_idle_enter() into a single
irq disabled section. This way no interrupt happening in-between would
needlessly process any RCU job.

Now we are talking about an optimization for which benefits
have yet to be measured. Let's start simple and completely decouple
idle rcu and dyntick idle logics to simplify.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2bbb6817c0ac1b5f2a68d720f364f98eeb1ac4fd 08-Oct-2011 Frederic Weisbecker <fweisbec@gmail.com> nohz: Allow rcu extended quiescent state handling seperately from tick stop

It is assumed that rcu won't be used once we switch to tickless
mode and until we restart the tick. However this is not always
true, as in x86-64 where we dereference the idle notifiers after
the tick is stopped.

To prepare for fixing this, add two new APIs:
tick_nohz_idle_enter_norcu() and tick_nohz_idle_exit_norcu().

If no use of RCU is made in the idle loop between
tick_nohz_enter_idle() and tick_nohz_exit_idle() calls, the arch
must instead call the new *_norcu() version such that the arch doesn't
need to call rcu_idle_enter() and rcu_idle_exit().

Otherwise the arch must call tick_nohz_enter_idle() and
tick_nohz_exit_idle() and also call explicitly:

- rcu_idle_enter() after its last use of RCU before the CPU is put
to sleep.
- rcu_idle_exit() before the first use of RCU after the CPU is woken
up.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
280f06774afedf849f0b34248ed6aff57d0f6908 07-Oct-2011 Frederic Weisbecker <fweisbec@gmail.com> nohz: Separate out irq exit and idle loop dyntick logic

The tick_nohz_stop_sched_tick() function, which tries to delay
the next timer tick as long as possible, can be called from two
places:

- From the idle loop to start the dytick idle mode
- From interrupt exit if we have interrupted the dyntick
idle mode, so that we reprogram the next tick event in
case the irq changed some internal state that requires this
action.

There are only few minor differences between both that
are handled by that function, driven by the ts->inidle
cpu variable and the inidle parameter. The whole guarantees
that we only update the dyntick mode on irq exit if we actually
interrupted the dyntick idle mode, and that we enter in RCU extended
quiescent state from idle loop entry only.

Split this function into:

- tick_nohz_idle_enter(), which sets ts->inidle to 1, enters
dynticks idle mode unconditionally if it can, and enters into RCU
extended quiescent state.

- tick_nohz_irq_exit() which only updates the dynticks idle mode
when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called).

To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed
into tick_nohz_idle_exit().

This simplifies the code and micro-optimize the irq exit path (no need
for local_irq_save there). This also prepares for the split between
dynticks and rcu extended quiescent state logics. We'll need this split to
further fix illegal uses of RCU in extended quiescent states in the idle
loop.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
11ed0ba1754841316d4095478944300acf19acc3 14-Nov-2011 Will Deacon <will.deacon@arm.com> ARM: 7161/1: errata: no automatic store buffer drain

This patch implements a workaround for PL310 erratum 769419. On
revisions of the PL310 prior to r3p2, the Store Buffer does not
automatically drain. This can cause normal, non-cacheable writes to be
retained when the memory system is idle, leading to suboptimal I/O
performance for drivers using coherent DMA.

This patch adds an optional wmb() call to the cpu_idle loop. On systems
with an outer cache, this causes an explicit flush of the store buffer.

Cc: stable@vger.kernel.org
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
e879c862fb81b986095ae7a4676b2281c2f97957 01-Nov-2011 Russell King <rmk+kernel@arm.linux.org.uk> ARM: restart: only perform setup for restart when soft-restarting

We only need to set the system up for a soft-restart if we're going to
be doing a soft-restart. Provide a new function (soft_restart()) which
does the setup and final call for this, and make platforms use it.
Eliminate the call to setup_restart() from the default handler.

This means that platforms arch_reset() function is no longer called with
the page tables prepared for a soft-restart, and caches will still be
enabled.

Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Krzysztof Ha■asa <khc@pm.waw.pl>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Acked-by: Wan ZongShun <mcuos.com@gmail.com>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
5aafec15bdc54cf0722696c95091d7bd674bfcad 01-Nov-2011 Russell King <rmk+kernel@arm.linux.org.uk> ARM: restart: remove argument to setup_mm_for_reboot()

setup_mm_for_reboot() doesn't make use of its argument, so remove it.

Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ac15e00b1efe705b66a36d1a6a9db7f6ed524c43 31-Oct-2011 Russell King <rmk+kernel@arm.linux.org.uk> ARM: restart: move reboot failure handing into machine_restart()

Move the failure to reboot into machine_restart() to always catch
this condition, even if a platform decides to hook the restarting
via arm_pm_restart().

Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ecea4ab6d3d8bb4122522398200f1cd2a06af6d5 22-Jul-2011 Paul Gortmaker <paul.gortmaker@windriver.com> arm: convert core files from module.h to export.h

Many of the core ARM kernel files are not modules, but just
including module.h for exporting symbols. Now these files can
use the lighter footprint export.h for this role.

There are probably lots more, but ARM files of mach-* and plat-*
don't get coverage via a simple yesconfig build. They will have
to be cleaned up and tested via using their respective configs.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
b380ab4f85d641574d91b12b333848a0731a497c 31-Aug-2011 Laura Abbott <lauraa@codeaurora.org> ARM: 7068/1: process: change from __backtrace to dump_stack in show_regs

Currently, show_regs calls __backtrace which does
nothing if CONFIG_FRAME_POINTER is not set. Switch to
dump_stack which handles both CONFIG_FRAME_POINTER and
CONFIG_ARM_UNWIND correctly.

__backtrace is now superseded by dump_stack in general
and show_regs was the last caller so remove __backtrace
as well.

Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
cbc158d6bfa1990f7869717bb5270867c66068d1 04-Aug-2011 David Brown <davidb@codeaurora.org> cpuidle: Consistent spelling of cpuidle_idle_call()

Commit a0bfa1373859e9d11dc92561a8667588803e42d8 mispells
cpuidle_idle_call() on ARM and SH code. Fix this to be consistent.

Cc: Kevin Hilman <khilman@deeprootsystems.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: x86@kernel.org
Cc: Len Brown <len.brown@intel.com>
Signed-off-by: David Brown <davidb@codeaurora.org>
[ Also done by Mark Brown - th ebug has been around forever, and was
noticed in -next, but the idle tree never picked it up. Bad bad bad ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
a0bfa1373859e9d11dc92561a8667588803e42d8 02-Apr-2011 Len Brown <len.brown@intel.com> cpuidle: stop depending on pm_idle

cpuidle users should call cpuidle_call_idle() directly
rather than via (pm_idle)() function pointer.

Architecture may choose to continue using (pm_idle)(),
but cpuidle need not depend on it:

my_arch_cpu_idle()
...
if(cpuidle_call_idle())
pm_idle();

cc: Kevin Hilman <khilman@deeprootsystems.com>
cc: Paul Mundt <lethal@linux-sh.org>
cc: x86@kernel.org
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2e82669acf03e5bf2080f5d3ef005168e67d8a51 06-Apr-2011 Catalin Marinas <catalin.marinas@arm.com> ARM: 6867/1: Introduce THREAD_NOTIFY_COPY for copy_thread() hooks

This patch adds THREAD_NOTIFY_COPY for calling registered handlers
during the copy_thread() function call. It also changes the VFP handler
to use a switch statement rather than if..else and ignore this event.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
6cde6d4217ff01422c093d3f7ff550b7a324e96e 11-Jan-2011 Will Deacon <will.deacon@arm.com> ARM: 6619/1: nommu: avoid mapping vectors page when !CONFIG_MMU

When running without an MMU, we do not need to install a mapping for the
vectors page. Attempting to do so causes a compile-time error because
install_special_mapping is not defined.

This patch adds compile-time guards to the vector mapping functions
so that we can build nommu configurations once more.

Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
c7b0aff44a0740eedd31b759fd08d9e25672fa76 01-Oct-2010 Kevin Hilman <khilman@deeprootsystems.com> ARM: 6428/1: add cpu_idle_wait() to support CPUidle on SMP systems.

In order for CPUidle to work on SMP systems, an implementation of
cpu_idle_wait() is needed.

This patch duplicates the x86 implementation of cpu_idle_wait() for
ARM.

Tested-by: Colin Cross <ccross@android.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ec706dab290c486837d4a825870ab052bf200279 27-Aug-2010 Nicolas Pitre <nico@fluxnic.net> ARM: add a vma entry for the user accessible vector page

The kernel makes the high vector page visible to user space. This page
contains (amongst others) small code segments that can be executed in
user space. Make this page visible through ptrace and /proc/<pid>/mem
in order to let gdb perform code parsing needed for proper unwinding.

For example, the ERESTART_RESTARTBLOCK handler actually has a stack
frame -- it returns to a PC value stored on the user's stack. To
unwind after a "sleep" system call was interrupted twice, GDB would
have to recognize this situation and understand that stack frame
layout -- which it currently cannot do.

We could fix this by hard-coding addresses in the vector page range into
GDB, but that isn't really portable as not all of those addresses are
guaranteed to remain stable across kernel releases. And having the gdb
process make an exception for this page and get content from its own
address space for it looks strange, and it is not future proof either.

Being located above PAGE_OFFSET, this vma cannot be deleted by
user space code.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
864232fa1a2f8dfe003438ef0851a56722740f3e 03-Sep-2010 Will Deacon <will.deacon@arm.com> ARM: 6357/1: hw-breakpoint: add new ptrace requests for hw-breakpoint interaction

For debuggers to take advantage of the hw-breakpoint framework in the kernel,
it is necessary to expose the API calls via a ptrace interface.

This patch exposes the hardware breakpoints framework as a collection of
virtual registers, accesible using PTRACE_SETHBPREGS and PTRACE_GETHBPREGS
requests. The breakpoints are stored in the debug_info struct of the running
thread.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: S. Karthikeyan <informkarthik@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
3d3f78d752bfada5b6041f2f7bd0833d8bdf7a4a 26-Jul-2010 Russell King <rmk+kernel@arm.linux.org.uk> ARM: call machine_shutdown() from machine_halt(), etc

x86 calls machine_shutdown() from the various machine_*() calls which
take the machine down ready for halting, restarting, etc, and uses
this to bring the system safely to a point where those actions can be
performed. Such actions are stopping the secondary CPUs.

So, change the ARM implementation of these to reflect what x86 does.

This solves kexec problems on ARM SMP platforms, where the secondary
CPUs were left running across the kexec call.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
9ca03a21e320a6bf44559323527aba704bcc8772 26-Jul-2010 Russell King <rmk+kernel@arm.linux.org.uk> ARM: Factor out common code from cpu_proc_fin()

All implementations of cpu_proc_fin() start by disabling interrupts
and then flush caches. Rather than have every processors proc_fin()
implementation do this, move it out into generic code - and move the
cache flush past setup_mm_for_reboot() (so it can benefit from having
caches still enabled.)

This allows cpu_proc_fin() to become independent of the L1/L2 cache
types, and eventually move the L2 cache flushing into the L2 support
code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ac78884e6d89714d18b32b5b7d574116ecfb7c88 10-Jul-2010 Russell King <rmk+kernel@arm.linux.org.uk> ARM: lockdep: fix unannotated irqs-on

CPU: Testing write buffer coherency: ok
------------[ cut here ]------------
WARNING: at kernel/lockdep.c:3145 check_flags+0xcc/0x1dc()
Modules linked in:
[<c0035120>] (unwind_backtrace+0x0/0xf8) from [<c0355374>] (dump_stack+0x20/0x24)
[<c0355374>] (dump_stack+0x20/0x24) from [<c0060c04>] (warn_slowpath_common+0x58/0x70)
[<c0060c04>] (warn_slowpath_common+0x58/0x70) from [<c0060c3c>] (warn_slowpath_null+0x20/0x24)
[<c0060c3c>] (warn_slowpath_null+0x20/0x24) from [<c008f224>] (check_flags+0xcc/0x1dc)
[<c008f224>] (check_flags+0xcc/0x1dc) from [<c00945dc>] (lock_acquire+0x50/0x140)
[<c00945dc>] (lock_acquire+0x50/0x140) from [<c0358434>] (_raw_spin_lock+0x50/0x88)
[<c0358434>] (_raw_spin_lock+0x50/0x88) from [<c00fd114>] (set_task_comm+0x2c/0x60)
[<c00fd114>] (set_task_comm+0x2c/0x60) from [<c007e184>] (kthreadd+0x30/0x108)
[<c007e184>] (kthreadd+0x30/0x108) from [<c0030104>] (kernel_thread_exit+0x0/0x8)
---[ end trace 1b75b31a2719ed1c ]---
possible reason: unannotated irqs-on.
irq event stamp: 3
hardirqs last enabled at (2): [<c0059bb0>] finish_task_switch+0x48/0xb0
hardirqs last disabled at (3): [<c002f0b0>] ret_slow_syscall+0xc/0x1c
softirqs last enabled at (0): [<c005f3e0>] copy_process+0x394/0xe5c
softirqs last disabled at (0): [<(null)>] (null)

Fix this by ensuring that the lockdep interrupt state is manipulated in
the appropriate places. We essentially treat userspace as an entirely
separate environment which isn't relevant to lockdep (lockdep doesn't
monitor userspace.) We don't tell lockdep that IRQs will be enabled
in that environment.

Instead, when creating kernel threads (which is a rare event compared
to entering/leaving userspace) we have to update the lockdep state. Do
this by starting threads with IRQs disabled, and in the kthread helper,
tell lockdep that IRQs are enabled, and enable them.

This provides lockdep with a consistent view of the current IRQ state
in kernel space.

This also revert portions of 0d928b0b616d1c5c5fe76019a87cba171ca91633
which didn't fix the problem.

Tested-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
c743f38013aeff58ef6252601e397b5ba281c633 25-May-2010 Nicolas Pitre <nico@fluxnic.net> ARM: initial stack protector (-fstack-protector) support

This is the very basic stuff without the changing canary upon
task switch yet. Just the Kconfig option and a constant canary
value initialized at boot time.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
990cb8acf23cab19a2930f1ed5e7dc108f89079b 14-Jun-2010 Nicolas Pitre <nico@fluxnic.net> [ARM] implement arch_randomize_brk()

For this feature to take effect, CONFIG_COMPAT_BRK must be turned
off. This can safely be turned off for any EABI user space versions.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
4260415f6a3b92c5c986398d96c314df37a4ccbf 19-Apr-2010 Russell King <rmk+kernel@arm.linux.org.uk> ARM: fix build error in arch/arm/kernel/process.c

/tmp/ccJ3ssZW.s: Assembler messages:
/tmp/ccJ3ssZW.s:1952: Error: can't resolve `.text' {.text section} - `.LFB1077'

This is caused because:

.section .data
.section .text
.section .text
.previous

does not return us to the .text section, but the .data section; this
makes use of .previous dangerous if the ordering of previous sections
is not known.

Fix up the other users of .previous; .pushsection and .popsection are
a safer pairing to use than .section and .previous.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
5a0e3ad6af8660be21ca98a971cd00f331318c05 24-Mar-2010 Tejun Heo <tj@kernel.org> include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
22325525d8bb1478daddefec1b762e7882bcd515 08-Jan-2010 Rabin Vincent <rabin@rab.in> ARM: 5868/1: ARM: fix "BUG: using smp_processor_id() in preemptible code"

Fix the following warning, which appears when the register dump for a
faulting process is printed in a kernel with SMP, DEBUG_PREEMPT, and
DEBUG_USER (with user_debug=31) enabled:

BUG: using smp_processor_id() in preemptible [00000000] code: init/1
caller is __show_regs+0x18/0x234
Backtrace:
[<c0159e5c>] (dump_backtrace+0x0/0x114) from [<c01faf30>] (dump_stack+0x18/0x1c)
r6:c781a000 r5:c0157544 r4:00000001 r3:00000000
[<c01faf18>] (dump_stack+0x0/0x1c) from [<c01e5230>] (debug_smp_processor_id+0xc4/0xf8)
[<c01e516c>] (debug_smp_processor_id+0x0/0xf8) from [<c0157544>] (__show_regs+0x18/0x234)
r6:c781bfb0 r5:00000000 r4:c781bfb0 r3:00000000
[<c015752c>] (__show_regs+0x0/0x234) from [<c01577a0>] (show_regs+0x40/0x50)
[<c0157760>] (show_regs+0x0/0x50) from [<c015c968>] (__do_user_fault+0x5c/0xa4)
r4:c781c000 r3:00000000
[<c015c90c>] (__do_user_fault+0x0/0xa4) from [<c015cbe0>] (do_page_fault+0x1b4/0x1e4)
r7:00000000 r6:00010000 r5:c781bfb0 r4:c781c000
[<c015ca2c>] (do_page_fault+0x0/0x1e4) from [<c01554c8>] (do_DataAbort+0x3c/0xa0)
[<c015548c>] (do_DataAbort+0x0/0xa0) from [<c01560c4>] (ret_from_exception+0x0/0x10)

Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
797245f5da543074ee7db0e0516da744c89aa17f 18-Dec-2009 Russell King <rmk+kernel@arm.linux.org.uk> ARM: Convert VFP/Crunch/XscaleCP thread_release() to exit_thread()

This avoids races in the VFP code where the dead thread may have
state on another CPU. By moving this code to exit_thread(), we
will be running as the thread, and therefore be running on the
current CPU.

This means that we can ensure that the only local state is accessed
in the thread notifiers.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
cde3f8607350666c4dd120dbbdbd9c70ffb2ea61 13-Oct-2009 Artem Bityutskiy <dedekind1@gmail.com> ARM: 5759/1: Add register information of threads to coredump

Defines ELF_CORE_COPY_TASK_REGS so that CPU register information
of every thread is included in coredump. Without this, only the faulting
thread is coredumped.

Cc: Roger Quadros <ext-roger.quadros@nokia.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
b86040a59feb255a8193173caa4d5199464433d5 24-Jul-2009 Catalin Marinas <catalin.marinas@arm.com> Thumb-2: Implementation of the unified start-up and exceptions code

This patch implements the ARM/Thumb-2 unified kernel start-up and
exception handling code.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
9ccdac3662dbf3c75e8f8851a214bdf7d365a4bd 22-Jun-2009 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] idle: clean up pm_idle calling, obey hlt_counter

pm_idle is used by infrastructure (eg, cpuidle) which expects architectures
to call it in a certain way. Arrange for ARM to follow x86's lead on this
and call pm_idle() with interrupts already disabled. However, we expect
pm_idle() to enable interrupts before it returns.

Also, OMAP wants to be able to disable hlt-ing, so allow hlt_counter to
prevent all calls to pm_idle.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
feb97c3644a560ffdf9a17c65b1df807b5b4432f 19-Jun-2009 Catalin Marinas <catalin.marinas@arm.com> [ARM] 5559/1: Limit the stack unwinding caused by a kthread exit

When a kthread function returns, it branches to do_exit(). However, the
unwinding information isn't valid anymore and any stack trace caused by
do_exit() may be incorrect. This patch adds a kernel_thread_exit()
function and annotated with '.cantunwind' so that the unwinder stops
when reaching it.

Tested-by: Tony Lindgren <tony@atomide.com>

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
26584853a44c58f3d6ac7360d697a2ddcd1a3efa 30-May-2009 Catalin Marinas <catalin.marinas@arm.com> Add core support for ARMv6/v7 big-endian

Starting with ARMv6, the CPUs support the BE-8 variant of big-endian
(byte-invariant). This patch adds the core support:

- setting of the BE-8 mode via the CPSR.E register for both kernel and
user threads
- big-endian page table walking
- REV used to rotate instructions read from memory during fault
processing as they are still little-endian format
- Kconfig and Makefile support for BE-8. The --be8 option must be passed
to the final linking stage to convert the instructions to
little-endian

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
6f2c55b843836d26528c56a0968689accaedbc67 03-Apr-2009 Alexey Dobriyan <adobriyan@gmail.com> Simplify copy_thread()

First argument unused since 2.3.11.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
be093beb608edf821b45fe00a8a080fb5c6ed4af 19-Mar-2009 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] pass reboot command line to arch_reset()

OMAP wishes to pass state to the boot loader upon reboot in order to
instruct it whether to wait for USB-based reflashing or not. There is
already a facility to do this via the reboot() syscall, except we ignore
the string passed to machine_restart().

This patch fixes things to pass this string to arch_reset(). This means
that we keep the reboot mode limited to telling the kernel _how_ to
perform the reboot which should be independent of what we request the
boot loader to do.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2d7c11bfc91637e5f9bc5f8c9a82aaffcc0e97aa 11-Feb-2009 Catalin Marinas <catalin.marinas@arm.com> [ARM] 5382/1: unwind: Reorganise the stacktrace support

This patch changes the walk_stacktrace and its callers for easier
integration of stack unwinding. The arch/arm/kernel/stacktrace.h file is
also moved to arch/arm/include/asm/stacktrace.h.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
33fa9b13285e76fb95d940120964562e4c7081c2 06-Sep-2008 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] Convert asm/uaccess.h to linux/uaccess.h

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
1de765c1e940e23d83ec57035769e8af003f8796 06-Sep-2008 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] remove pc_pointer()

pc_pointer() was a function to mask the PC for 26-bit ARMs, which
we no longer support. Remove it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
09d9bae064724635df3920bcca47e077cfb23e76 05-Sep-2008 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] sparse: fix several warnings

arch/arm/kernel/process.c:270:6: warning: symbol 'show_fpregs' was not declared. Should it be static?

This function isn't used, so can be removed.

arch/arm/kernel/setup.c:532:9: warning: symbol 'len' shadows an earlier one
arch/arm/kernel/setup.c:524:6: originally declared here

A function containing two 'len's.

arch/arm/mm/fault-armv.c:188:13: warning: symbol 'check_writebuffer_bugs' was not declared. Should it be static?
arch/arm/mm/mmap.c:122:5: warning: symbol 'valid_phys_addr_range' was not declared. Should it be static?
arch/arm/mm/mmap.c:137:5: warning: symbol 'valid_mmap_phys_addr_range' was not declared. Should it be static?

Missing includes.

arch/arm/kernel/traps.c:71:77: warning: Using plain integer as NULL pointer
arch/arm/mm/ioremap.c:355:46: error: incompatible types in comparison expression (different address spaces)

Sillies.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
a09e64fbc0094e3073dbb09c3b4bfe4ab669244b 05-Aug-2008 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach

This just leaves include/asm-arm/plat-* to deal with.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
b8f8c3cf0a4ac0632ec3f0e15e9dc0c29de917af 18-Jul-2008 Thomas Gleixner <tglx@linutronix.de> nohz: prevent tick stop outside of the idle loop

Jack Ren and Eric Miao tracked down the following long standing
problem in the NOHZ code:

scheduler switch to idle task
enable interrupts

Window starts here

----> interrupt happens (does not set NEED_RESCHED)
irq_exit() stops the tick

----> interrupt happens (does set NEED_RESCHED)

return from schedule()

cpu_idle(): preempt_disable();

Window ends here

The interrupts can happen at any point inside the race window. The
first interrupt stops the tick, the second one causes the scheduler to
rerun and switch away from idle again and we end up with the tick
disabled.

The fact that it needs two interrupts where the first one does not set
NEED_RESCHED and the second one does made the bug obscure and extremly
hard to reproduce and analyse. Kudos to Jack and Eric.

Solution: Limit the NOHZ functionality to the idle loop to make sure
that we can not run into such a situation ever again.

cpu_idle()
{
preempt_disable();

while(1) {
tick_nohz_stop_sched_tick(1); <- tell NOHZ code that we
are in the idle loop

while (!need_resched())
halt();

tick_nohz_restart_sched_tick(); <- disables NOHZ mode
preempt_enable_no_resched();
schedule();
preempt_disable();
}
}

In hindsight we should have done this forever, but ...

/me grabs a large brown paperbag.

Debugged-by: Jack Ren <jack.ren@marvell.com>,
Debugged-by: eric miao <eric.y.miao@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
205bee6ad804d7034773b5978c74dde495df2301 20-Apr-2008 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] dyntick: Remove obsolete and unused ARM dyntick support

dyntick is superseded by the clocksource/clockevent infrastructure,
using the NO_HZ configuration option. No one implements dyntick on
ARM anymore, so it's pointless keeping it around. Remove dyntick
support.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
1eb114112381eb66ebacdace1b6e70d30d603f9c 08-Feb-2008 David Howells <dhowells@redhat.com> aout: remove unnecessary inclusions of {asm, linux}/a.out.h

Remove now unnecessary inclusions of {asm,linux}/a.out.h.

[akpm@linux-foundation.org: fix alpha build]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
7fa3031500ec9b0a7460c8c23751799006ffee74 08-Feb-2008 David Howells <dhowells@redhat.com> aout: suppress A.OUT library support if !CONFIG_ARCH_SUPPORTS_AOUT

Suppress A.OUT library support if CONFIG_ARCH_SUPPORTS_AOUT is not set.

Not all architectures support the A.OUT binfmt, so the ELF binfmt should not
be permitted to go looking for A.OUT libraries to load in such a case. Not
only that, but under such conditions A.OUT core dumps are not produced either.

To make this work, this patch also does the following:

(1) Makes the existence of the contents of linux/a.out.h contingent on
CONFIG_ARCH_SUPPORTS_AOUT.

(2) Renames dump_thread() to aout_dump_thread() as it's only called by A.OUT
core dumping code.

(3) Moves aout_dump_thread() into asm/a.out-core.h and makes it inline. This
is then included only where needed. This means that this bit of arch
code will be stored in the appropriate A.OUT binfmt module rather than
the core kernel.

(4) Drops A.OUT support for Blackfin (according to Mike Frysinger it's not
needed) and FRV.

This patch depends on the previous patch to move STACK_TOP[_MAX] out of
asm/a.out.h and into asm/processor.h as they're required whether or not A.OUT
format is available.

[jdike@addtoit.com: uml: re-remove accidentally restored code]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
19c5870c0eefd27c6d09d867465e0571262e05d0 19-Oct-2007 Alexey Dobriyan <adobriyan@openvz.org> Use helpers to obtain task pid in printks (arch code)

One of the easiest things to isolate is the pid printed in kernel log.
There was a patch, that made this for arch-independent code, this one makes
so for arch/xxx files.

It took some time to cross-compile it, but hopefully these are all the
printks in arch code.

Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
909d6c6c80311f800aee338e5fa528818b115951 26-Jun-2007 George G. Davis <gdavis@mvista.com> [ARM] 4453/1: Fully Decode ARM instruction set state in show_regs() tombstone

The ARM show_regs() tombstone only partially decodes which ARM ISA was
executing at the time a fault occurred displaying either "(T)" for the
Thumb case or nothing at all for other cases. This patch therefore
explicitly identifies which state the processor is in at the time of
a fault: ARM, Thumb, Jazelle or JazelleEE.

Signed-off-by: George G. Davis <gdavis@mvista.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
154c772ebfb12ef66855510e6be2b12c85110b0c 18-Jun-2007 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] Update show_regs/oops register format

Add the kernel release and version information to the output of
show_regs/oops. Add the CPU PSR register. Avoid using printk
to output partial lines; always output a complete line.

Re-combine the "Control" and "Table + DAC" lines after nommu
separated them; we don't want to waste vertical screen space
needlessly.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
9e4559ddffc012a73ea0b54ed3b6a219c1483ae9 14-Mar-2007 Kevin Hilman <khilman@mvista.com> [ARM] 4258/2: Support for dynticks in idle loop

And, wrap timer_tick() and sysdev suspend/resume in
!GENERIC_CLOCKEVENTS since clockevent layer takes care
of these.

Signed-off-by: Kevin Hilman <khilman@mvista.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
0f0a00beb80624a446ba7c0152cd171008eeab2e 03-Mar-2007 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] Remove needless linux/ptrace.h includes

Lots of places in arch/arm were needlessly including linux/ptrace.h,
resumably because we used to pass a struct pt_regs to interrupt
handlers. Now that we don't, all these ptrace.h includes are
redundant.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ae0a846e411dc0b568e8ccda584896310ee5f369 09-Jan-2007 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] Move processor_modes[] to .../process.c

bad_mode() currently prints the mode which caused the exception, and
then causes an oops dump to be printed which again displays this
information (since the CPSR in the struct pt_regs is correct.) This
leads to processor_modes[] being shared between traps.c and process.c
with a local declaration of it.

We can clean this up by moving processor_modes[] to process.c and
removing the duplication, resulting in processor_modes[] becoming
static.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
122214428a7bfab2c09b417f3acdb06222e81748 02-Nov-2006 Paul Gortmaker <paul.gortmaker@gmail.com> [ARM] 3911/2: Simplify alloc_thread_info on ARM

Remove ARM local cache of 4 struct thread_info.
Can cause oops under certain circumstances.

Russell indicated the original optimization was
required on older kernels to avoid thread starvation
on memory fragmentation, but may no longer be
required. I've updated the patch to 19rc4 and
ensured no <config.h> dain-bramage slipped in this
time (sorry about that).

Original description follows:

I was given some test results which pointed to an
Oops in alloc_thread_info (happened 2x), and after
looking at the code, I see that ARM has its own
local cache of 4 struct thread_info. There wasn't
any clear (to me) synchronization between the
alloc_thread_info and the free_thread_info.

I looked over the other arch, and they all simply
allocate them on an as needed basis, so I simplified
the ARM to do the same, based on the other arch
(e.g. PPC) and the folks doing the testing have
indicated that this fixed the oops.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
f12d0d7c7786af39435ef6ae9defe47fb58f6091 26-Sep-2006 Hyok S. Choi <hyok.choi@samsung.com> [ARM] nommu: manage the CP15 things

All the current CP15 access codes in ARM arch can be categorized and
conditioned by the defines as follows:

Related operation Safe condition
a. any CP15 access !CPU_CP15
b. alignment trap CPU_CP15_MMU
c. D-cache(C-bit) CPU_CP15
d. I-cache CPU_CP15 && !( CPU_ARM610 || CPU_ARM710 ||
CPU_ARM720 || CPU_ARM740 ||
CPU_XSCALE || CPU_XSC3 )
e. alternate vector CPU_CP15 && !CPU_ARM740
f. TTB CPU_CP15_MMU
g. Domain CPU_CP15_MMU
h. FSR/FAR CPU_CP15_MMU

For example, alternate vector is supported if and only if
"CPU_CP15 && !CPU_ARM740" is satisfied.

Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ae95bfbb2b67eba5d67a0478a8715682a87e2616 01-Jul-2006 Lennert Buytenhek <buytenh@wantstofly.org> [ARM] 3707/1: iwmmxt: use the generic thread notifier infrastructure

Patch from Lennert Buytenhek

This patch makes the iWMMXt context switch hook use the generic
thread notifier infrastructure that was recently merged in commit
d6551e884cf66de072b81f8b6d23259462c40baf.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
6ab3d5624e172c553004ecc862bfeac16d9d68b7 30-Jun-2006 Jörn Engel <joern@wohnheim.fh-wedel.de> Remove obsolete #include <linux/config.h>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
d6551e884cf66de072b81f8b6d23259462c40baf 21-Jun-2006 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] Add thread_notify infrastructure

Some machine classes need to allow VFP support to be built into the
kernel, but still allow the kernel to run even though VFP isn't
present. Unfortunately, the kernel hard-codes VFP instructions
into the thread switch, which prevents this being run-time selectable.

Solve this by introducing a notifier which things such as VFP can
hook into to be informed of events which affect the VFP subsystem
(eg, creation and destruction of threads, switches between threads.)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
74617fb6b825ea370ae72565f7543306bc08ef6e 19-Jun-2006 Richard Purdie <rpurdie@rpsys.net> [ARM] 3593/1: Add reboot and shutdown handlers for Zaurus handhelds

Patch from Richard Purdie

Add functionality to allow machine specific reboot handlers on ARM.
Add machine specific reboot and poweroff handlers for all PXA Zaurus
models.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
9d494ccb9ca297f80dc61a0d6357e88c86f44e92 16-May-2006 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] arch/arm/kernel/process.c: Fix warning

arch/arm/kernel/process.c:314: warning: assignment makes integer from pointer without a cast

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
1929ab8c6860a4a94109eed038b0fa9d12c81721 09-May-2006 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] Fix thread struct allocator for SMP case

The ARM thread struct allocator is racy on SMP systems. Fix it by
turning it into a per-cpu based allocator. This also allows keeps
the cache cache warm for thread structs and kernel stacks.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
0cb3463f04e771869f481e2dd44f66419e850586 31-Mar-2006 Adrian Bunk <bunk@stusta.de> [PATCH] unexport get_wchan

The only user of get_wchan is the proc fs - and proc can't be built modular.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
84dff1a73013dbdd7d770c332ab84cbfed24741b 16-Mar-2006 Ben Dooks <ben-linux@fluff.org> [ARM] 3363/1: [cleanup] process.c - fix warnings

Patch from Ben Dooks

Fix the following warnings from sparse:

arch/arm/kernel/process.c:86:6: warning: symbol 'default_idle' was not declared. Should it be static?
arch/arm/kernel/process.c:378:5: warning: symbol 'dump_fpu' was not declared. Should it be static?

Include <linux/elfcore.h> for dump_fpu() decleration, and
make default_idle() static as it is not used outside the file.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
32d39a9355780bc9aadcf76a2d2004bdbe0f4665 12-Jan-2006 Al Viro <viro@ftp.linux.org.uk> [PATCH] arm: task_stack_page()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
552058239238342dfd2fa8d33a299a162b1a4f05 12-Jan-2006 Al Viro <viro@ftp.linux.org.uk> [PATCH] arm: end_of_stack()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
815d5ec86eb8d5f57e5e4aa147bd1fb6338c58ac 12-Jan-2006 Al Viro <viro@ftp.linux.org.uk> [PATCH] arm: task_pt_regs()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
e7c1b32fd354c34c4dceb1736a485bc5d91f7c43 12-Jan-2006 Al Viro <viro@ftp.linux.org.uk> [PATCH] arm: task_thread_info()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
78ff18a412da24a4b79c6a97000ef5e467e813da 03-Jan-2006 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] Cleanup ARM includes

arch/arm/kernel/entry-armv.S has contained a comment suggesting
that asm/hardware.h and asm/arch/irqs.h should be moved into the
asm/arch/entry-macro.S include. So move the includes to these
two files as required.

Add missing includes (asm/hardware.h, asm/io.h) to asm/arch/system.h
includes which use those facilities, and remove asm/io.h from
kernel/process.c.

Remove other unnecessary includes from arch/arm/kernel, arch/arm/mm
and arch/arm/mach-footbridge.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
64c7c8f88559624abdbe12b5da6502e8879f8d28 09-Nov-2005 Nick Piggin <nickpiggin@yahoo.com.au> [PATCH] sched: resched and cpu_idle rework

Make some changes to the NEED_RESCHED and POLLING_NRFLAG to reduce
confusion, and make their semantics rigid. Improves efficiency of
resched_task and some cpu_idle routines.

* In resched_task:
- TIF_NEED_RESCHED is only cleared with the task's runqueue lock held,
and as we hold it during resched_task, then there is no need for an
atomic test and set there. The only other time this should be set is
when the task's quantum expires, in the timer interrupt - this is
protected against because the rq lock is irq-safe.

- If TIF_NEED_RESCHED is set, then we don't need to do anything. It
won't get unset until the task get's schedule()d off.

- If we are running on the same CPU as the task we resched, then set
TIF_NEED_RESCHED and no further action is required.

- If we are running on another CPU, and TIF_POLLING_NRFLAG is *not* set
after TIF_NEED_RESCHED has been set, then we need to send an IPI.

Using these rules, we are able to remove the test and set operation in
resched_task, and make clear the previously vague semantics of
POLLING_NRFLAG.

* In idle routines:
- Enter cpu_idle with preempt disabled. When the need_resched() condition
becomes true, explicitly call schedule(). This makes things a bit clearer
(IMO), but haven't updated all architectures yet.

- Many do a test and clear of TIF_NEED_RESCHED for some reason. According
to the resched_task rules, this isn't needed (and actually breaks the
assumption that TIF_NEED_RESCHED is only cleared with the runqueue lock
held). So remove that. Generally one less locked memory op when switching
to the idle thread.

- Many idle routines clear TIF_POLLING_NRFLAG, and only set it in the inner
most polling idle loops. The above resched_task semantics allow it to be
set until before the last time need_resched() is checked before going into
a halt requiring interrupt wakeup.

Many idle routines simply never enter such a halt, and so POLLING_NRFLAG
can be always left set, completely eliminating resched IPIs when rescheduling
the idle task.

POLLING_NRFLAG width can be increased, to reduce the chance of resched IPIs.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
5bfb5d690f36d316a5f3b4f7775fda996faa6b12 09-Nov-2005 Nick Piggin <nickpiggin@yahoo.com.au> [PATCH] sched: disable preempt in idle tasks

Run idle threads with preempt disabled.

Also corrected a bugs in arm26's cpu_idle (make it actually call schedule()).
How did it ever work before?

Might fix the CPU hotplugging hang which Nigel Cunningham noted.

We think the bug hits if the idle thread is preempted after checking
need_resched() and before going to sleep, then the CPU offlined.

After calling stop_machine_run, the CPU eventually returns from preemption and
into the idle thread and goes to sleep. The CPU will continue executing
previous idle and have no chance to call play_dead.

By disabling preemption until we are ready to explicitly schedule, this bug is
fixed and the idle threads generally become more robust.

From: alexs <ashepard@u.washington.edu>

PPC build fix

From: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>

MIPS build fix

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
c906107bb72b7bd5ecfc98cc807bdb8f34d17501 09-Nov-2005 Nicolas Pitre <nico@cam.org> [ARM] 3100/1: simplify a pointer computation

Patch from Nicolas Pitre

Looks clearer this way.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
a054a811597a17ffbe92bc4db04a4dc2f1b1ea55 02-Nov-2005 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM SMP] Add hotplug CPU infrastructure

This patch adds the infrastructure to support hotplug CPU on ARM
platforms.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
59586e5a262a29361c45c929ea3253d4aec830b0 26-Jul-2005 Eric W. Biederman <ebiederm@xmission.com> [PATCH] Don't export machine_restart, machine_halt, or machine_power_off.

machine_restart, machine_halt and machine_power_off are machine
specific hooks deep into the reboot logic, that modules
have no business messing with. Usually code should be calling
kernel_restart, kernel_halt, kernel_power_off, or
emergency_restart. So don't export machine_restart,
machine_halt, and machine_power_off so we can catch buggy users.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2ea83398b75309d8fdc999c4bb252e72d7e4fd9d 27-Jun-2005 Russell King <rmk@dyn-67.arm.linux.org.uk> [PATCH] ARM: Add VST idle loop call

This call allows the dynamic tick support to reprogram the timer
immediately before the CPU idles.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
4f7a18124c1a44858fb74a1c4234015009952959 05-May-2005 Russell King <rmk@dyn-67.arm.linux.org.uk> [PATCH] ARM: Fix kernel stack offset calculations

Various places in the ARM kernel implicitly assumed that kernel
stacks are always 8K due to hard coded constants. Replace these
constants with definitions.

Correct the allowable range of kernel stack pointer values within
the allocation. Arrange for the entire kernel stack to be zeroed,
not just the upper 4K if CONFIG_DEBUG_STACK_USAGE is set.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
652a12ef98d16ccd1ee5cdf2c832ce5411ed3262 17-Apr-2005 Russell King <rmk@dyn-67.arm.linux.org.uk> [PATCH] ARM: showregs

Fix show_regs() to provide a backtrace. Provide a new __show_regs()
function which implements the common subset of show_regs() and die().
Add prototypes to asm-arm/system.h

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 17-Apr-2005 Linus Torvalds <torvalds@ppc970.osdl.org> Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!