Commit Graph

157181 Commits

Author SHA1 Message Date
Thomas Gleixner
47926214d8 x86: Replace the now identical time_32/64.c by time.c
Remove the redundant copy.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
ef4512882d x86: time_32/64.c unify profile_pc
The code is identical except for the formatting and a useless
#ifdef. Make it the same.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
08047c4f17 x86: Move calibrate_cpu to tsc.c
Move the code where it's only user is. Also we need to look whether
this hardwired hackery might interfere with perfcounters.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
454ede7eeb x86: Make timer setup and global variables the same in time_32/64.c
The timer and timer irq setup code is identical in 32 and 64 bit. Make
it the same formatting as well. Also add the global variables under
the necessary ifdefs to both files.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
0be6939422 x86: Remove mca bus ifdef from timer interrupt
MCA_bus is constant 0 when CONFIG_MCA=n. So the compiler removes that
code w/o needing an extra #ifdef

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
64fcbac1f3 x86: Simplify timer_ack magic in time_32.c
Let the compiler optimize the timer_ack magic away in the 32bit timer
interrupt and put the same code into time_64.c. It's optimized out for
CONFIG_X86_IO_APIC on 32bit and for 64bit because timer_ack is const 0
in both cases.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
dd3e6e8c6e x86: Prepare unification of time_32/64.c
Unify the top comment and the includes.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
ecce85089e x86: Remove do_timer hook
This is a left over of the old x86 sub arch support. Remove it and
open code it like we do in time_64.c

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
845b3944bb x86: Add timer_init to x86_init_ops
The timer init code is convoluted with several quirks and the paravirt
timer chooser. Figuring out which code path is actually taken is not
for the faint hearted.

Move the numaq TSC quirk to tsc_pre_init x86_init_ops function and
replace the paravirt time chooser and the remaining x86 quirk with a
simple x86_init_ops function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
736decac64 x86: Move percpu clockevents setup to x86_init_ops
paravirt overrides the setup of the default apic timers as per cpu
timers. Moorestown needs to override that as well.

Move it to x86_init_ops setup and create a separate x86_cpuinit struct
which holds the function for the secondary evtl. hotplugabble CPUs.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner
f1d7062a23 x86: Move xen_post_allocator_init into xen_pagetable_setup_done
We really do not need two paravirt/x86_init_ops functions which are
called in two consecutive source lines. Move the only user of
post_allocator_init into the already existing pagetable_setup_done
function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
030cb6c00d x86: Move paravirt pagetable_setup to x86_init_ops
Replace more paravirt hackery by proper x86_init_ops.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
6f30c1ac3f x86: Move paravirt banner printout to x86_init_ops
Replace another obscure paravirt magic and move it to
x86_init_ops. Such a hook is also useful for embedded and special
hardware.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
42bbdb43b1 x86: Replace ARCH_SETUP by a proper x86_init_ops
ARCH_SETUP is a horrible leftover from the old arch/i386 mach support
code. It still has a lonely user in xen. Move it to x86_init_ops.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
428cf9025b x86: Move traps_init to x86_init_ops
Replace the quirks by a simple x86_init_ops function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
66bcaf0bde x86: Move irq_init to x86_init_ops
irq_init is overridden by x86_quirks and by paravirts. Unify the whole
mess and make it an unconditional x86_init_ops function which defaults
to the standard function and can be overridden by the early platform
code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
d9112f4302 x86: Move pre_intr_init to x86_init_ops
Replace the quirk machinery by a x86_init_ops function which
defaults to the standard implementation. This is also a preparatory
patch for Moorestown support which needs to replace the default
init_ISA_irqs as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
b3f1b617f4 x86: Move get/find_smp_config to x86_init_ops
Replace the quirk machinery by a x86_init_ops function which defaults
to the standard implementation.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner
90e1c6969d x86: Move oem_bus_info to x86_init_ops
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:53 +02:00
Thomas Gleixner
52fdb56846 x86: Move mpc_oem_pci_bus to x86_init_ops
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
Thomas Gleixner
72302142e1 x86: Move smp_read_mpc_oem to x86_init_ops.
Move smp_read_mpc_oem from quirks to x86_init.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
Thomas Gleixner
fd6c666149 x86: Move mpc_apic_id to x86_init_ops
The mpc_apic_id setup is handled by a x86_quirk. Make it a
x86_init_ops function with a default implementation.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
Thomas Gleixner
de93410310 x86: Move ioapic_ids_setup to x86_init_ops
32bit and also the numaq code have special requirements on the
ioapic_id setup. Convert it to a x86_init_ops function and get rid
of the quirks and #ifdefs

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
Thomas Gleixner
f4848472cd x86: Sanitize smp_record and move it to x86_init_ops
The x86 quirkification introduced an extra ugly hackery with a
variable pointer in the mpparse code. If the pointer is initialized
then it is dereferenced and the variable set to 0 or incremented.

Create a x86_init_ops function and let the affected numaq code
hold the function. Default init is a setup noop.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
Thomas Gleixner
6b18ae3e2f x86: Move memory_setup to x86_init_ops
memory_setup is overridden by x86_quirks and by paravirts with weak
functions and quirks. Unify the whole mess and make it an
unconditional x86_init_ops function which defaults to the standard
function and can be overridden by the early platform code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
Thomas Gleixner
816c25e7d4 x86: Add reserve_ebda_region to x86_init_ops
reserve_ebda_region needs to be called befor start_kernel. Moorestown
needs to override it. Make it a x86_init_ops function and initialize
it with the default reserve_ebda_region.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
Thomas Gleixner
8fee697d99 x86: Add request_standard_resources to x86_init
The 32bit and the 64bit code are slighty different in the reservation
of standard resources. Also the upcoming Moorestown support needs its
own version of that.

Add it to x86_init_ops and initialize it with the 64bit default. 32bit
overrides it in early boot. Now moorestown can add it's own override
w/o sprinkling the code with more #ifdefs

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
Thomas Gleixner
f7cf5a5b8c x86: Add probe_roms to x86_init
probe_roms is only used on 32bit. Add it to the x86_init ops and
remove the #ifdefs.

Default initializer is x86_init_noop() which is overridden in
the 32bit boot code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
Thomas Gleixner
57844a8f8e x86: Add x86_init infrastructure
The upcoming Moorestown support brings the embedded world to x86. The
setup code of x86 has already a couple of hooks which are either
x86_quirks or paravirt ops. Some of those setup hooks are pretty
convoluted like the timer setup and the tsc calibration code. But
there are other places which could do with a cleanup.

Instead of having inline functions/macros which are modified at
compile time I decided to introduce x86_init ops which are
unconditional in the code and make it clear that they can be changed
either during compile time or in the early boot process. The function
pointers are initialized by default functions which can be noops so
that the pointer can be called unconditionally in the most cases. This
also allows us to remove 32bit/64bit, paravirt and other #ifdeffery.

paravirt guests are just a hardware platform in the setup code, so we
should treat them as such and not hide all behind multiple layers of
indirection and compile time dependencies.

It's more obvious that x86_init.timers.timer_init() is a function
pointer than the late_time_init = choose_time_init() obscurity. It's
also way simpler to grep for x86_init.timers.timer_init and find all
the places which modify that function pointer instead of analyzing
weak functions, macros and paravirt indirections.

Note. This is not a general paravirt_ops replacement. It just will
move setup related hooks which are potentially useful for other
platform setup purposes as well out of the paravirt domain.

Add the base infrastructure without any functionality.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
Thomas Gleixner
4152f93508 Merge branch 'sched/clock' into x86/cleanups
Reason: The tsc init cleanup depends on sched_clock_init moving past
late_time_init.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:06:24 +02:00
Thomas Gleixner
6effcd9245 Merge branch 'x86/paravirt' into x86/cleanups
Reason: The setup cleanups conflict with the paravirt cleanups. Avoid
a rather large merge conflict

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 16:42:32 +02:00
Thomas Gleixner
fa84e9eecf init: Move sched_clock_init after late_time_init
Some architectures initialize clocks and timers in late_time_init and
x86 wants to do the same to avoid FIXMAP hackery for calibrating the
TSC. That would result in undefined sched_clock readout and wreckaged
printk timestamps again. We probably have those already on archs which
do all their time/clock setup in late_time_init.

There is no harm to move that after late_time_init except that a few
more boot timestamps are stale. The scheduler is not active at that
point so no real wreckage is expected.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Cc: linux-arch@vger.kernel.org
2009-08-27 16:38:18 +02:00
Linus Torvalds
1e23502cc5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  virtio: net refill on out-of-memory
  smc91x: fix compilation on SMP
2009-08-26 20:54:48 -07:00
Linus Torvalds
e99b1f22f9 Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/ps3: Update ps3_defconfig
  powerpc/ps3: Add missing check for PS3 to rtc-ps3 platform device registration
2009-08-26 20:39:31 -07:00
Geoff Levand
b080f187ad powerpc/ps3: Update ps3_defconfig
Update ps3_defconfig.

 o Refresh for 2.6.31.
 o Remove MTD support.
 o Add more HID drivers.

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-27 13:27:59 +10:00
Geert Uytterhoeven
7b6a09f3d6 powerpc/ps3: Add missing check for PS3 to rtc-ps3 platform device registration
On non-PS3, we get:

| kernel BUG at drivers/rtc/rtc-ps3.c:36!

because the rtc-ps3 platform device is registered unconditionally in a kernel
with builtin support for PS3.

Reported-by: Sachin Sant <sachinp@in.ibm.com>
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Acked-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-27 13:25:46 +10:00
Linus Torvalds
5311034ddd Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  IMA: iint put in ima_counts_get and put
2009-08-26 20:17:07 -07:00
Linus Torvalds
533995ed85 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  m68k,m68knommu: Wire up rt_tgsigqueueinfo and perf_counter_open
  m68k: Fix redefinition of pgprot_noncached
  arch/m68k/include/asm/motorola_pgalloc.h: fix kunmap arg
  m68k: cnt reaches -1, not 0
  m68k: count can reach 51, not 50
2009-08-26 20:16:38 -07:00
Thadeu Lima de Souza Cascardo
cc674c81f0 leds: after setting inverted attribute, we must update the LED
If we change the inverted attribute to another value, the LED will not be
inverted until we change the GPIO state.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Cc: Samuel R. C. Vale <srcvale@holoscopio.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:53 -07:00
Thadeu Lima de Souza Cascardo
48cccd26f3 leds: fix multiple requests and releases of IRQ for GPIO LED Trigger
When setting the same GPIO number, multiple IRQ shared requests will be
done without freing the previous request.  It will also try to free a
failed request or an already freed IRQ if 0 was written to the gpio file.

All these oops and leaks were fixed with the following solution: keep the
previous allocated GPIO (if any) still allocated in case the new request
fails.  The alternative solution would desallocate the previous allocated
GPIO and set gpio as 0.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Samuel R. C. Vale <srcvale@holoscopio.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:53 -07:00
Frans Pop
bdf57de4e6 acpi processor: remove superfluous warning message
This failure is very common on many platforms.  Handling it in the ACPI
processor driver is enough, and we don't need a warning message unless
CONFIG_ACPI_DEBUG is set.

Based on a patch from Zhang Rui.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13389

Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:53 -07:00
Frans Pop
2a908002c7 ACPI processor: force throttling state when BIOS returns incorrect value
If the BIOS reports an invalid throttling state (which seems to be
fairly common after system boot), a reset is done to state T0.
Because of a check in acpi_processor_get_throttling_ptc(), the reset
never actually gets executed, which results in the error reoccurring
on every access of for example /proc/acpi/processor/CPU0/throttling.

Add a 'force' option to acpi_processor_set_throttling() to ensure
the reset really takes effect.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13389

This patch, together with the next one, fixes a regression introduced in
2.6.30, listed on the regression list. They have been available for 2.5
months now in bugzilla, but have not been picked up, despite various
reminders and without any reason given.

Google shows that numerous people are hitting this issue. The issue is in
itself relatively minor, but the bug in the code is clear.

The patches have been in all my kernels and today testing has shown that
throttling works correctly with the patches applied when the system
overheats (http://bugzilla.kernel.org/show_bug.cgi?id=13918#c14).

Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:53 -07:00
Costantino Leandro
f3d83e2415 wmi: fix kernel panic when stack protection enabled.
Summary:
Kernel panic arise when stack protection is enabled, since strncat will
add a null terminating byte '\0'; So in functions
like this one (wmi_query_block):
        char wc[4]="WC";
	....
	strncat(method, block->object_id, 2);
        ...
the length of wc should be n+1 (wc[5]) or stack protection
fault will arise. This is not noticeable when stack protection is
disabled,but , isn't good either.
Config used: [CONFIG_CC_STACKPROTECTOR_ALL=y,
	      CONFIG_CC_STACKPROTECTOR=y]

Panic Trace
------------
       .... stack-protector: kernel stack corrupted in : fa7b182c
       2.6.30-rc8-obelisco-generic
       call_trace:
           [<c04a6c40>] ? panic+0x45/0xd9
	   [<c012925d>] ? __stack_chk_fail+0x1c/0x40
	   [<fa7b182c>] ? wmi_query_block+0x15a/0x162 [wmi]
	   [<fa7b182c>] ? wmi_query_block+0x15a/0x162 [wmi]
	   [<fa7e7000>] ? acer_wmi_init+0x00/0x61a [acer_wmi]
	   [<fa7e7135>] ? acer_wmi_init+0x135/0x61a [acer_wmi]
	   [<c0101159>] ? do_one_initcall+0x50+0x126

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13514

Signed-off-by: Costantino Leandro <lcostantino@gmail.com>
Signed-off-by: Carlos Corbacho <carlos@strangeworlds.co.uk>
Cc: Len Brown <len.brown@intel.com>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:53 -07:00
Yinghai Lu
ce8442b551 acpi: don't call acpi_processor_init if acpi is disabled
Jens reported early_ioremap messages with old ASUS board...

> [    1.507461] pci 0000:00:09.0: Firmware left e100 interrupts enabled; disabling
> [    1.532778] early_ioremap(3fffd080, 0000005c) [0] => Pid: 1, comm: swapper Not tainted 2.6.31-rc4 #36
> [    1.561007] Call Trace:
> [    1.568638]  [<c136e48b>] ? printk+0x18/0x1d
> [    1.581734]  [<c15513ff>] __early_ioremap+0x74/0x1e9
> [    1.596898]  [<c15515aa>] early_ioremap+0x1a/0x1c
> [    1.611270]  [<c154a187>] __acpi_map_table+0x18/0x1a
> [    1.626451]  [<c135a7f8>] acpi_os_map_memory+0x1d/0x25
> [    1.642129]  [<c119459c>] acpi_tb_verify_table+0x20/0x49
> [    1.658321]  [<c1193e50>] acpi_get_table_with_size+0x53/0xa1
> [    1.675553]  [<c1193eae>] acpi_get_table+0x10/0x15
> [    1.690192]  [<c155cc19>] acpi_processor_init+0x23/0xab
> [    1.706126]  [<c1001043>] do_one_initcall+0x33/0x180
> [    1.721279]  [<c155cbf6>] ? acpi_processor_init+0x0/0xab
> [    1.737479]  [<c106893a>] ? register_irq_proc+0xaa/0xc0
> [    1.753411]  [<c10689b7>] ? init_irq_proc+0x67/0x80
> [    1.768316]  [<c15405e7>] kernel_init+0x120/0x176
> [    1.782678]  [<c15404c7>] ? kernel_init+0x0/0x176
> [    1.797062]  [<c10038b7>] kernel_thread_helper+0x7/0x10
> [    1.812984] 00000080 + ffe00000

that is rather later.
acpi_gbl_permanent_mmap should be set in acpi_early_init()
if acpi is not disabled

and we have
> [    0.000000] ASUS P2B-DS detected: force use of acpi=ht

just don't load acpi_processor_init...

Reported-and-tested-by: Jens Rosenboom <jens@leia.mcbone.net>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:52 -07:00
Michael Brunner
0d288162f2 thermal_sys: check get_temp return value
The return value of the get_temp function is not checked when doing a
thermal zone update.  This may lead to a critical shutdown if get_temp
fails and the content of the temp variable is incorrectly set higher than
the critical trip point.

This has been observed on a system with incorrect ACPI implementation
where the corresponding methods were not serialized and therefore
sometimes triggered ACPI errors (AE_ALREADY_EXISTS).  The following
critical shutdowns indicated a temperature of 2097 C, which was obviously
wrong.

The patch adds a return value check that jumps over all trip point
evaluations printing a warning if get_temp fails.  The trip points are
evaluated again on the next polling interval with successful get_temp
execution.

Signed-off-by: Michael Brunner <mibru@gmx.de>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:52 -07:00
Oleg Nesterov
4ab6c08336 clone(): fix race between copy_process() and de_thread()
Spotted by Hiroshi Shimamoto who also provided the test-case below.

copy_process() uses signal->count as a reference counter, but it is not.
This test case

	#include <sys/types.h>
	#include <sys/wait.h>
	#include <unistd.h>
	#include <stdio.h>
	#include <errno.h>
	#include <pthread.h>

	void *null_thread(void *p)
	{
		for (;;)
			sleep(1);

		return NULL;
	}

	void *exec_thread(void *p)
	{
		execl("/bin/true", "/bin/true", NULL);

		return null_thread(p);
	}

	int main(int argc, char **argv)
	{
		for (;;) {
			pid_t pid;
			int ret, status;

			pid = fork();
			if (pid < 0)
				break;

			if (!pid) {
				pthread_t tid;

				pthread_create(&tid, NULL, exec_thread, NULL);
				for (;;)
					pthread_create(&tid, NULL, null_thread, NULL);
			}

			do {
				ret = waitpid(pid, &status, 0);
			} while (ret == -1 && errno == EINTR);
		}

		return 0;
	}

quickly creates an unkillable task.

If copy_process(CLONE_THREAD) races with de_thread()
copy_signal()->atomic(signal->count) breaks the signal->notify_count
logic, and the execing thread can hang forever in kernel space.

Change copy_process() to increment count/live only when we know for sure
we can't fail.  In this case the forked thread will take care of its
reference to signal correctly.

If copy_process() fails, check CLONE_THREAD flag.  If it it set - do
nothing, the counters were not changed and current belongs to the same
thread group.  If it is not set, ->signal must be released in any case
(and ->count must be == 1), the forked child is the only thread in the
thread group.

We need more cleanups here, in particular signal->count should not be used
by de_thread/__exit_signal at all.  This patch only fixes the bug.

Reported-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Tested-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:52 -07:00
Minchan Kim
03ef83af52 mm: fix for infinite churning of mlocked pages
An mlocked page might lose the isolatation race.  This causes the page to
clear PG_mlocked while it remains in a VM_LOCKED vma.  This means it can
be put onto the [in]active list.  We can rescue it by using try_to_unmap()
in shrink_page_list().

But now, As Wu Fengguang pointed out, vmscan has a bug.  If the page has
PG_referenced, it can't reach try_to_unmap() in shrink_page_list() but is
put into the active list.  If the page is referenced repeatedly, it can
remain on the [in]active list without being moving to the unevictable
list.

This patch fixes it.

Reported-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KOSAKI Motohiro <<kosaki.motohiro@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:52 -07:00
David Rientjes
b62e408c05 flex_array: convert element_nr formals to unsigned
It's problematic to allow signed element_nr's or total's to be passed as
part of the flex array API.

flex_array_alloc() allows total_nr_elements to be set to a negative
quantity, which is obviously erroneous.

flex_array_get() and flex_array_put() allows negative array indices in
dereferencing an array part, which could address memory mapped before
struct flex_array.

The fix is to convert all existing element_nr formals to be qualified as
unsigned.  Existing checks to compare it to total_nr_elements or the max
array size based on element_size need not be changed.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:52 -07:00
David Rientjes
8e7ee27095 flex_array: declare parts member to have incomplete type
The `parts' member of struct flex_array should evaluate to an incomplete
type so that sizeof() cannot be used and C99 does not require the
zero-length specification.

Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:52 -07:00
David Rientjes
105b6e8a74 flex_array: fix flex_array_free_parts comment
flex_array_free_parts() does not take `src' or `element_nr' formals, so
remove their respective comments.

Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:52 -07:00