linux-stable.git/arch/arm/kernel/process.c, branch linux-2.6.36.y

Merge branch 'devel-stable' into devel

2010-07-31T13:20:16+00:00

Conflicts:
	arch/arm/kernel/entry-armv.S
	arch/arm/kernel/setup.c
	arch/arm/mm/init.c

ARM: call machine_shutdown() from machine_halt(), etc

2010-07-27T09:48:43+00:00

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

ARM: Factor out common code from cpu_proc_fin()

2010-07-27T09:48:42+00:00

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

Merge git://git.kernel.org/pub/scm/linux/kernel/git/nico/orion into devel-stable

2010-07-21T08:22:45+00:00

ARM: lockdep: fix unannotated irqs-on

2010-07-10T09:53:13+00:00

CPU: Testing write buffer coherency: ok
------------[ cut here ]------------
WARNING: at kernel/lockdep.c:3145 check_flags+0xcc/0x1dc()
Modules linked in:
[] (unwind_backtrace+0x0/0xf8) from [] (dump_stack+0x20/0x24)
[] (dump_stack+0x20/0x24) from [] (warn_slowpath_common+0x58/0x70)
[] (warn_slowpath_common+0x58/0x70) from [] (warn_slowpath_null+0x20/0x24)
[] (warn_slowpath_null+0x20/0x24) from [] (check_flags+0xcc/0x1dc)
[] (check_flags+0xcc/0x1dc) from [] (lock_acquire+0x50/0x140)
[] (lock_acquire+0x50/0x140) from [] (_raw_spin_lock+0x50/0x88)
[] (_raw_spin_lock+0x50/0x88) from [] (set_task_comm+0x2c/0x60)
[] (set_task_comm+0x2c/0x60) from [] (kthreadd+0x30/0x108)
[] (kthreadd+0x30/0x108) from [] (kernel_thread_exit+0x0/0x8)
---[ end trace 1b75b31a2719ed1c ]---
possible reason: unannotated irqs-on.
irq event stamp: 3
hardirqs last  enabled at (2): [] finish_task_switch+0x48/0xb0
hardirqs last disabled at (3): [] ret_slow_syscall+0xc/0x1c
softirqs last  enabled at (0): [] 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 
Signed-off-by: Russell King

ARM: initial stack protector (-fstack-protector) support

2010-06-15T01:31:00+00:00

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

[ARM] implement arch_randomize_brk()

2010-06-15T01:22:11+00:00

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

ARM: fix build error in arch/arm/kernel/process.c

2010-04-21T07:45:21+00:00

/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

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

2010-03-30T13:02:32+00:00

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 
Guess-its-ok-by: Christoph Lameter 
Cc: Ingo Molnar 
Cc: Lee Schermerhorn

ARM: 5868/1: ARM: fix "BUG: using smp_processor_id() in preemptible code"

2010-01-08T16:14:29+00:00

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:
[] (dump_backtrace+0x0/0x114) from [] (dump_stack+0x18/0x1c)
 r6:c781a000 r5:c0157544 r4:00000001 r3:00000000
[] (dump_stack+0x0/0x1c) from [] (debug_smp_processor_id+0xc4/0xf8)
[] (debug_smp_processor_id+0x0/0xf8) from [] (__show_regs+0x18/0x234)
 r6:c781bfb0 r5:00000000 r4:c781bfb0 r3:00000000
[] (__show_regs+0x0/0x234) from [] (show_regs+0x40/0x50)
[] (show_regs+0x0/0x50) from [] (__do_user_fault+0x5c/0xa4)
 r4:c781c000 r3:00000000
[] (__do_user_fault+0x0/0xa4) from [] (do_page_fault+0x1b4/0x1e4)
 r7:00000000 r6:00010000 r5:c781bfb0 r4:c781c000
[] (do_page_fault+0x0/0x1e4) from [] (do_DataAbort+0x3c/0xa0)
[] (do_DataAbort+0x0/0xa0) from [] (ret_from_exception+0x0/0x10)

Signed-off-by: Rabin Vincent 
Signed-off-by: Russell King