Miles Lane reported the following error:
2 locks held by cat/4179:
  #0:  (&p->lock){+.+.+.}, at: [<c10a3884>] seq_read+0x25/0x315
  #1:  (&dev_priv->mm.active_list_lock){+.+...}, at: [<c119a854>]
i915_batchbuffer_info+0x2b/0x124
Pid: 4179, comm: cat Not tainted 2.6.32-rc5-git1 #2
Call Trace:
  [<c104874f>] ? __debug_show_held_locks+0x1e/0x20
  [<c1023fb0>] __might_sleep+0xf0/0xf7
  [<c101c393>] kmap+0x17/0x58
  [<c119a8d6>] i915_batchbuffer_info+0xad/0x124
  [<c10a39bf>] seq_read+0x160/0x315
  [<c108fb8c>] ? rw_verify_area+0x98/0xbb
  [<c10a385f>] ? seq_read+0x0/0x315
  [<c1090331>] vfs_read+0x75/0xa9
  [<c10903f9>] sys_read+0x3b/0x5d
  [<c1002a8f>] sysenter_do_call+0x12/0x36

The fix is relatively simple, use the atomic variants of kmap() that
avoid the potential sleep.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Miles Lane <miles.lane@gmail.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

* 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xen: mask extended topology info in cpuid
  xen/hvc: make sure console output is always emitted, with explicit polling

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:
  sysfs: Don't leak secdata when a sysfs_dirent is freed.

Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix kthread_bind() by moving the body of kthread_bind() to sched.c
  sched: Disable SD_PREFER_LOCAL at node level
  sched: Fix boot crash by zalloc()ing most of the cpu masks
  sched: Strengthen buddies and mitigate buddy induced latencies

Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  ftrace: Fix unmatched locking in ftrace_regex_write()
  ring-buffer: Synchronize resizing buffer with reader lock

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, fs: Fix x86 procfs stack information for threads on 64-bit
  x86: Add reboot quirk for 3 series Mac mini
  x86: Fix printk message typo in mtrr cleanup code
  dma-debug: Fix compile warning with PAE enabled
  x86/amd-iommu: Un__init function required on shutdown
  x86/amd-iommu: Workaround for erratum 63

* 'for-linus' of git://www.linux-m32r.org/git/takata/linux-2.6_dev:
  m32r: Should index be positive?
  m32r: bzip2/lzma kernel compression support
  m32r: add NOTES to vmlinux.lds.S to remove .note.gnu.build-id section
  arch/m32r: Use DIV_ROUND_CLOSEST

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp:
  amd64_edac: fix CECCs reporting
  amd64_edac: fix a wrong goto clause in amd64_edac.c

Not a single line of actual code in the function was really
fundamentally correct.

Problems ranged from lack of proper range checking, to removing the last
character written (which admittedly is usually '\n'), to not accepting
hex numbers even though the 'show' routine would show the data in that
format.

This tries to do better.
Acked-by: Michael Buesch <mb@bu3sch.de>
Tested-and-acked-by: Jack Steiner <steiner@sgi.com>
Cc: stable@kernel.org
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Michael Gilbert <michael.s.gilbert@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

While refreshing my sysfs patches I noticed a leak in the secdata
implementation.  We don't free the secdata when we free the
sysfs dirent.

This is a bug in 2.6.32-rc5 that we really should close.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel:
  drm/i915: Ironlake suspend/resume support
  drm/i915: kill warning in intel_find_pll_g4x_dp
  drm/i915: update watermarks before enabling PLLs
  drm/i915: add FIFO watermark support for G4x
  drm/i915: quiet DP i2c init
  drm/i915: fix panel fitting filter coefficient select for Ironlake
  drm/i915: fix to setup display reference clock control on Ironlake
  drm/i915: Install a fence register for fbc on g4x
  drm/i915: save/restore BLC histogram control reg across suspend/resume
  drm/i915: Fix FDI M/N setting according with correct color depth
  drm/i915: disable powersave feature for Ironlake currently
  drm/i915: Fix render reclock availability detection.
  drm/i915: Save and restore the GM45 FBC regs on suspend and resume.
  drm/i915: Set the LVDS_BORDER when using LVDS scaling mode
  drm/i915: disable FBC for Pineview, fixing a boot hang.

Shift error type bits properly.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>

In amd64_edac_init(void) in amd64_edac.c, cache_k8_northbridges() is
called before pci_register_driver. If it fails, should exit with err
directly.
Signed-off-by: Li Hong <lihong.hi@gmail.com>
Acked-by: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>

This patch fixes two issues in the procfs stack information on
x86-64 linux.

The 32 bit loader compat_do_execve did not store stack
start. (this was figured out by Alexey Dobriyan).

The stack information on a x64_64 kernel always shows 0 kbyte
stack usage, because of a missing implementation of the KSTK_ESP
macro which always returned -1.

The new implementation now returns the right value.
Signed-off-by: Stefani Seibold <stefani@seibold.net>
Cc: Americo Wang <xiyou.wangcong@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <1257240160.4889.24.camel@wall-e>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

When a command is passed to the set_ftrace_filter, then
the ftrace_regex_lock is still held going back to user space.

 # echo 'do_open : foo' > set_ftrace_filter
 (still holding ftrace_regex_lock when returning to user space!)
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AEF7F8A.3080300@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

We got a sudden panic when we reduced the size of the
ringbuffer.

We can reproduce the panic by the following steps:

echo 1 > events/sched/enable
cat trace_pipe > /dev/null &

while ((1))
do
echo 12000 > buffer_size_kb
echo 512 > buffer_size_kb
done

(not more than 5 seconds, panic ...)
Reported-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
LKML-Reference: <4AF01735.9060409@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  cfq-iosched: limit coop preemption
  cfq-iosched: fix bad return value cfq_should_preempt()
  backing-dev: bdi sb prune should be in the unregister path, not destroy
  Fix bio_alloc() and bio_kmalloc() documentation
  bio_put(): add bio_clone() to the list of functions in the comment

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  sata_via: Remove redundant device ID for VIA VT8261
  drivers/ata/libata: Move dereference after NULL test
  ahci: Enable SB600 64bit DMA on MSI K9A2 Platinum v2

Index `ipi_num' is signed, test whether it is negative to
make sure we don't get a negative array element.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>

- Support bzip2 and lzma kernel compression for m32r.
- Clean up arch/m32r/boot/compressed/misc.c.
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>

Building with --build-id option, .note.gnu.build-id section is added
to vmlinux.bin.  But some old buggy binutils creates a huge vmlinux.bin,
and a bootloader fails to boot its zImage as well.

This patch adds a NOTES macro to a linker script vmlinux.ld.S to put
.note.gnu.build-id section into .note section.
Then, the .note section will be removed, because "-R .note" option is
specified in OBJCOPYFLAGS to make a vmlinux.bin binary.
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>

The kernel.h macro DIV_ROUND_CLOSEST performs the computation (x + d/2)/d
but is perhaps more readable.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@haskernel@
@@

@depends on haskernel@
expression x,__divisor;
@@

- (((x) + ((__divisor) / 2)) / (__divisor))
+ DIV_ROUND_CLOSEST(x,__divisor)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>

Just remove redundant device ID for VIA VT8261.
The device ID 0x9000 and 0x9040 are redundant (for VT8261).
The 0x9040 is reserved for other usage.
Signed-off-by: Joseph Chan <josephchan@via.com.tw>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

In each case, if the NULL test on qc is needed, then the derefernce
should be after the NULL test.

A simplified version of the semantic match that detects this problem is as
follows (http://coccinelle.lip6.fr/):

// <smpl>
@match exists@
expression x, E;
identifier fld;
@@

* x->fld
  ... when != \(x = E\|&x\)
* x == NULL
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

Like the Asus M2A-VM, MSI's K9A2 Platinum (MS-7376) can also support 64bit
DMA. It is a new enough board that all the BIOS releases work correctly with
64bit DMA enabled.
Signed-off-by: Mark Nelson <mdnelson8@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

CFQ has an optimization for cooperated applications. if several
io-context have close requests, they will get boost. But the
optimization get abused. Considering thread a, b, which work on one
file. a reads sectors s, s+2, s+4, ...; b reads sectors s+1, s+3, s
+5, ... Both a and b are sequential read, so they can open idle window.
a reads a sector s and goes to idle window and wakeup b. b reads sector
s+1, since in current implementation, cfq_should_preempt() thinks a and
b are cooperators, b will preempt a. b then reads sector s+1 and goes to
idle window and wakeup a. for the same reason, a will preempt b and
reads s+2. a and b will continue the circle. The circle will be very
long, and a and b will occupy whole disk queue. Other applications will
nearly have no chance to run.

Fix this limiting coop preempt until a queue is scheduled normally
again.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

Commit a6151c3a inadvertently reversed
a preempt condition check, potentially causing a performance regression.
Make the meta check correct again.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

Commit 592b09a4 was different from
the tested path, in that it moved the bdi super_block prune from
unregister to destroy context. This doesn't fully fix the sync hang
bug on unexpected device removal, as need to prune the bdi cache
pointer before killing flusher thread.
Tested-by: Artur Skawina <art.08.09@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

* 'for-linus' of git://github.com/at91linux/linux-2.6-at91:
  at91: at91sam9g45 family: identify several chip versions
  avr32: add two new at91 to cpu.h definition

A Xen guest never needs to know about extended topology, and knowing
would just confuse it.

This patch just zeros ebx in leaf 0xb which indicates no topology info,
preventing a crash under Xen on cpus which support this leaf.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>

We never want to rely on the hvc workqueue to emit output, because the
most interesting output is when the kernel is broken.  This will
improve oops/crash/console message for better debugging.

Instead, we force-poll until all output is emitted.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>

cpu_is_xxx() macros are identifying generic at91sam9g45 chip. This patch adds
the capacity to differentiate Engineering Samples and final lots through the
inclusion of  at91_cpu_fully_identify() and the related chip IDs with chip
version field preserved.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>

Somme common drivers will need those at91 cpu_is_xxx() definitions. As
at91sam9g10 and at91sam9g45 are on the way to linus' tree, here is the patch
that adds those chips to cpu.h in AVR32 architecture.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>

* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (38 commits)
  MIPS: O32: Fix ppoll
  MIPS: Oprofile: Rename cpu_type from godson2 to loongson2
  MIPS: Alchemy: Fix hang with high-frequency edge interrupts
  MIPS: TXx9: Fix spi-baseclk value
  MIPS: bcm63xx: Set the correct BCM3302 CPU name
  MIPS: Loongson 2: Set cpu_has_dc_aliases and cpu_icache_snoops_remote_store
  MIPS: Avoid potential hazard on Context register
  MIPS: Octeon: Use lockless interrupt controller operations when possible.
  MIPS: Octeon: Use write_{un,}lock_irq{restore,save} to set irq affinity
  MIPS: Set S-cache linesize to 64-bytes for MTI's S-cache
  MIPS: SMTC: Avoid queing multiple reschedule IPIs
  MIPS: GCMP: Avoid accessing registers when they are not present
  MIPS: GIC: Random fixes and enhancements.
  MIPS: CMP: Fix memory barriers for correct operation of amon_cpu_start
  MIPS: Fix abs.[sd] and neg.[sd] emulation for NaN operands
  MIPS: SPRAM: Clean up support code a little
  MIPS: 1004K: Enable SPRAM support.
  MIPS: Malta: Enable PCI 2.1 compatibility in PIIX4
  MIPS: Kconfig: Fix duplicate default value for MIPS_L1_CACHE_SHIFT.
  MIPS: MTI: Fix accesses to device registers on MIPS boards
  ...

Merge branch 'iommu/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/linux-2.6-iommu into x86/urgent

* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  PM: Remove some debug messages producing too much noise
  PM: Fix warning on suspend errors
  PM / Hibernate: Add newline to load_image() fail path
  PM / Hibernate: Fix error handling in save_image()
  PM / Hibernate: Fix blkdev refleaks
  PM / yenta: Split resume into early and late parts (rev. 4)

nr_processes() returns the sum of the per cpu counter process_counts for
all online CPUs. This counter is incremented for the current CPU on
fork() and decremented for the current CPU on exit(). Since a process
does not necessarily fork and exit on the same CPU the process_count for
an individual CPU can be either positive or negative and effectively has
no meaning in isolation.

Therefore calculating the sum of process_counts over only the online
CPUs omits the processes which were started or stopped on any CPU which
has since been unplugged. Only the sum of process_counts across all
possible CPUs has meaning.

The only caller of nr_processes() is proc_root_getattr() which
calculates the number of links to /proc as
        stat->nlink = proc_root.nlink + nr_processes();

You don't have to be all that unlucky for the nr_processes() to return a
negative value leading to a negative number of links (or rather, an
apparently enormous number of links). If this happens then you can get
failures where things like "ls /proc" start to fail because they got an
-EOVERFLOW from some stat() call.

Example with some debugging inserted to show what goes on:
        # ps haux|wc -l
        nr_processes: CPU0:     90
        nr_processes: CPU1:     1030
        nr_processes: CPU2:     -900
        nr_processes: CPU3:     -136
        nr_processes: TOTAL:    84
        proc_root_getattr. nlink 12 + nr_processes() 84 = 96
        84
        # echo 0 >/sys/devices/system/cpu/cpu1/online
        # ps haux|wc -l
        nr_processes: CPU0:     85
        nr_processes: CPU2:     -901
        nr_processes: CPU3:     -137
        nr_processes: TOTAL:    -953
        proc_root_getattr. nlink 12 + nr_processes() -953 = -941
        75
        # stat /proc/
        nr_processes: CPU0:     84
        nr_processes: CPU2:     -901
        nr_processes: CPU3:     -137
        nr_processes: TOTAL:    -954
        proc_root_getattr. nlink 12 + nr_processes() -954 = -942
          File: `/proc/'
          Size: 0               Blocks: 0          IO Block: 1024   directory
        Device: 3h/3d   Inode: 1           Links: 4294966354
        Access: (0555/dr-xr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
        Access: 2009-11-03 09:06:55.000000000 +0000
        Modify: 2009-11-03 09:06:55.000000000 +0000
        Change: 2009-11-03 09:06:55.000000000 +0000

I'm not 100% convinced that the per_cpu regions remain valid for offline
CPUs, although my testing suggests that they do. If not then I think the
correct solution would be to aggregate the process_count for a given CPU
into a global base value in cpu_down().

This bug appears to pre-date the transition to git and it looks like it
may even have been present in linux-2.6.0-test7-bk3 since it looks like
the code Rusty patched in http://lwn.net/Articles/64773/ was already
wrong.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: gpio-keys - use IRQF_SHARED
  Input: winbond-cir - select LEDS_TRIGGERS
  Input: i8042 - try to get stable CTR value when initializing
  Input: atkbd - add a quirk for OQO 01+ multimedia keys

* 'fixes-s3c-2632-rc5' of git://git.fluff.org/bjdooks/linux:
  ARM: S3C2410: Fix sparse warnings in arch/arm/mach-s3c2410/gpio.c
  ARM: S3C2440: mini2440: Fix spare warnings
  ARM: S3C24XX: Fix warnings in arch/arm/plat-s3c24xx/gpio.c
  ARM: S3C2440: mini2440: Fix missing CONFIG_S3C_DEV_USB_HOST
  ARM: S3C24XX: arch/arm/plat-s3c24xx: Move dereference after NULL test
  ARM: S3C: Fix adc function exports
  ARM: S3C2410: Fix link if CONFIG_S3C2410_IOTIMING is not set
  ARM: S3C24XX: Introduce S3C2442B CPU
  ARM: S3C24XX: Define a macro to avoid compilation error
  ARM: S3C: Add info for supporting circular DMA buffers
  ARM: S3C64XX: Set rate of crystal mux
  ARM: S3C64XX: Fix S3C64XX_CLKDIV0_ARM_MASK value