Milan Broz [Mon, 23 Aug 2010 13:16:00 +0000 (15:16 +0200)]
loop: add some basic read-only sysfs attributes
Create /sys/block/loopX/loop directory and provide these attributes:
- backing_file
- autoclear
- offset
- sizelimit
This loop directory is present only if loop device is configured.
To be used in util-linux-ng (and possibly elsewhere like udev rules)
where code need to get loop attributes from kernel (and not store
duplicate info in userspace).
Moreover loop ioctls are not even able to provide full backing
file info because of buffer limits.
Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Linus Torvalds [Mon, 23 Aug 2010 02:55:14 +0000 (19:55 -0700)]
Merge branch 'radix-tree' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/xfsdev
* 'radix-tree' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/xfsdev:
radix-tree: radix_tree_range_tag_if_tagged() can set incorrect tags
radix-tree: clear all tags in radix_tree_node_rcu_free
Dave Chinner [Mon, 23 Aug 2010 00:33:53 +0000 (10:33 +1000)]
radix-tree: radix_tree_range_tag_if_tagged() can set incorrect tags
Commit ebf8aa44beed48cd17893a83d92a4403e5f9d9e2 ("radix-tree:
omplement function radix_tree_range_tag_if_tagged") does not safely
set tags on on intermediate tree nodes. The code walks down the tree
setting tags before it has fully resolved the path to the leaf under
the assumption there will be a leaf slot with the tag set in the
range it is searching.
Unfortunately, this is not a valid assumption - we can abort after
setting a tag on an intermediate node if we overrun the number of
tags we are allowed to set in a batch, or stop scanning because we
we have passed the last scan index before we reach a leaf slot with
the tag we are searching for set.
As a result, we can leave the function with tags set on intemediate
nodes which can be tripped over later by tag-based lookups. The
result of these stale tags is that lookup may end prematurely or
livelock because the lookup cannot make progress.
The fix for the problem involves reocrding the traversal path we
take to the leaf nodes, and only propagating the tags back up the
tree once the tag is set in the leaf node slot. We are already
recording the path for efficient traversal, so there is no
additional overhead to do the intermediately node tag setting in
this manner.
This fixes a radix tree lookup livelock triggered by the new
writeback sync livelock avoidance code introduced in commit f446daaea9d4a420d16c606f755f3689dcb2d0ce ("mm: implement writeback
livelock avoidance using page tagging").
Signed-off-by: Dave Chinner <dchinner@redhat.com> Acked-by: Jan Kara <jack@suse.cz>
Dave Chinner [Mon, 23 Aug 2010 00:33:19 +0000 (10:33 +1000)]
radix-tree: clear all tags in radix_tree_node_rcu_free
Commit f446daaea9d4a420d16c606f755f3689dcb2d0ce ("mm: implement
writeback livelock avoidance using page tagging") introduced a new
radix tree tag, increasing the number of tags in each node from 2 to
3. It did not, however, fix up the code in
radix_tree_node_rcu_free() that cleans up after radix_tree_shrink()
and hence could leave stray tags set in the new tag array.
The result is that the livelock avoidance code added in the the
above commit would hit stale tags when doing tag based lookups,
resulting in livelocks when trying to traverse the tree.
Fix this problem in radix_tree_node_rcu_free() so it doesn't happen
again in the future by using a loop to walk all the tags up to
RADIX_TREE_MAX_TAGS to clear the stray tags radix_tree_shrink()
leaves behind.
Signed-off-by: Dave Chinner <dchinner@redhat.com> Acked-by: Nick Piggin <npiggin@kernel.dk> Acked-by: Jan Kara <jack@suse.cz>
Linus Torvalds [Sun, 22 Aug 2010 18:27:36 +0000 (11:27 -0700)]
Merge branch 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: PIT: free irq source id in handling error path
KVM: destroy workqueue on kvm_create_pit() failures
KVM: fix poison overwritten caused by using wrong xstate size
Linus Torvalds [Sun, 22 Aug 2010 18:03:27 +0000 (11:03 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel: (58 commits)
drm/i915,intel_agp: Add support for Sandybridge D0
drm/i915: fix render pipe control notify on sandybridge
agp/intel: set 40-bit dma mask on Sandybridge
drm/i915: Remove the conflicting BUG_ON()
drm/i915/suspend: s/IS_IRONLAKE/HAS_PCH_SPLIT/
drm/i915/suspend: Flush register writes before busy-waiting.
i915: disable DAC on Ironlake also when doing CRT load detection.
drm/i915: wait for actual vblank, not just 20ms
drm/i915: make sure eDP PLL is enabled at the right time
drm/i915: fix VGA plane disable for Ironlake+
drm/i915: eDP mode set sequence corrections
drm/i915: add panel reset workaround
drm/i915: Enable RC6 on Ironlake.
drm/i915/sdvo: Only set is_lvds if we have a valid fixed mode.
drm/i915: Set up a render context on Ironlake
drm/i915 invalidate indirect state pointers at end of ring exec
drm/i915: Wake-up wait_request() from elapsed hang-check (v2)
drm/i915: Apply i830 errata for cursor alignment
drm/i915: Only update i845/i865 CURBASE when disabled (v2)
drm/i915: FBC is updated within set_base() so remove second call in mode_set()
...
Chris Wilson [Sun, 15 Aug 2010 09:52:34 +0000 (10:52 +0100)]
drm/i915: Remove the conflicting BUG_ON()
We now attempt to free "active" objects following a GPU hang as either
the GPU will be reset or the hang is permenant. In either case, the GPU
writes will not be flushed to main memory and it should be safe to
return that memory back to the system.
The BUG_ON(active) is thus overkill and can erroneously fire after a
EIO.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Eric Anholt <eric@anholt.net>
Jesse Barnes [Wed, 18 Aug 2010 20:20:54 +0000 (13:20 -0700)]
drm/i915: wait for actual vblank, not just 20ms
Waiting for a hard coded 20ms isn't always enough to make sure a vblank
period has actually occurred, so add code to make sure we really have
passed through a vblank period (or that the pipe is off when disabling).
This prevents problems with mode setting and link training, and seems to
fix a bug like https://bugs.freedesktop.org/show_bug.cgi?id=29278, but
on an HP 8440p instead. Hopefully also fixes
https://bugs.freedesktop.org/show_bug.cgi?id=29141.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Eric Anholt <eric@anholt.net>
Arjan van de Ven [Sat, 21 Aug 2010 20:07:26 +0000 (13:07 -0700)]
workqueue: Add basic tracepoints to track workqueue execution
With the introduction of the new unified work queue thread pools,
we lost one feature: It's no longer possible to know which worker
is causing the CPU to wake out of idle. The result is that PowerTOP
now reports a lot of "kworker/a:b" instead of more readable results.
This patch adds a pair of tracepoints to the new workqueue code,
similar in style to the timer/hrtimer tracepoints.
With this pair of tracepoints, the next PowerTOP can correctly
report which work item caused the wakeup (and how long it took):
Interrupt (43) i915 time 3.51ms wakeups 141
Work ieee80211_iface_work time 0.81ms wakeups 29
Work do_dbs_timer time 0.55ms wakeups 24
Process Xorg time 21.36ms wakeups 4
Timer sched_rt_period_timer time 0.01ms wakeups 1
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Samuel Thibault [Sat, 21 Aug 2010 19:32:41 +0000 (21:32 +0200)]
Replace Configure with Enable in description of MAXSMP
The "Configure" word tends to make user believe they have to say 'yes'
to be able to choose the number of procs/nodes. "Enable" should be
unambiguous enough.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 20 Aug 2010 23:49:40 +0000 (16:49 -0700)]
mm: make stack guard page logic use vm_prev pointer
Like the mlock() change previously, this makes the stack guard check
code use vma->vm_prev to see what the mapping below the current stack
is, rather than have to look it up with find_vma().
Also, accept an abutting stack segment, since that happens naturally if
you split the stack with mlock or mprotect.
Tested-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 20 Aug 2010 23:24:55 +0000 (16:24 -0700)]
mm: make the vma list be doubly linked
It's a really simple list, and several of the users want to go backwards
in it to find the previous vma. So rather than have to look up the
previous entry with 'find_vma_prev()' or something similar, just make it
doubly linked instead.
Tested-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tilman Sauerbeck [Fri, 20 Aug 2010 21:01:47 +0000 (14:01 -0700)]
mtd: nand: Fix probe of Samsung NAND chips
Apparently, the check for a 6-byte ID string introduced by commit 426c457a3216fac74e3d44dd39729b0689f4c7ab ("mtd: nand: extend NAND flash
detection to new MLC chips") is NOT sufficient to determine whether or
not a Samsung chip uses their new MLC detection scheme or the old,
standard scheme. This adds a condition to check cell type.
Signed-off-by: Tilman Sauerbeck <tilman@code-monkey.de> Signed-off-by: Brian Norris <norris@broadcom.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Cc: stable@kernel.org
Stefan Richter [Thu, 19 Aug 2010 21:13:43 +0000 (14:13 -0700)]
Documentation: kernel-locking: mutex_trylock cannot be used in interrupt context
Chapter 6 is right about mutex_trylock, but chapter 10 wasn't. This error
was introduced during semaphore-to-mutex conversion of the Unreliable
guide. :-)
If user context which performs mutex_lock() or mutex_trylock() is
preempted by interrupt context which performs mutex_trylock() on the same
mutex instance, a deadlock occurs. This is because these functions do not
disable local IRQs when they operate on mutex->wait_lock.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Matthew Wilcox <matthew@wil.cx> Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Thu, 19 Aug 2010 21:13:42 +0000 (14:13 -0700)]
drivers/scsi/qla4xxx: fix build
gcc-4.0.2:
drivers/scsi/qla4xxx/ql4_os.c: In function 'qla4_8xxx_error_recovery':
drivers/scsi/qla4xxx/ql4_glbl.h:135: sorry, unimplemented: inlining failed in call to 'qla4_8xxx_set_drv_active': function body not available
drivers/scsi/qla4xxx/ql4_os.c:2377: sorry, unimplemented: called from here
drivers/scsi/qla4xxx/ql4_glbl.h:135: sorry, unimplemented: inlining failed in call to 'qla4_8xxx_set_drv_active': function body not available
drivers/scsi/qla4xxx/ql4_os.c:2393: sorry, unimplemented: called from here
Cc: Ravi Anand <ravi.anand@qlogic.com> Cc: Vikas Chaudhary <vikas.chaudhary@qlogic.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miklos Szeredi [Thu, 19 Aug 2010 21:13:40 +0000 (14:13 -0700)]
uml: fix compile error in dma_get_cache_alignment()
Fix uml compile error:
include/linux/dma-mapping.h:145: error: redefinition of 'dma_get_cache_alignment'
arch/um/include/asm/dma-mapping.h:99: note: previous definition of 'dma_get_cache_alignment' was here
Introduced by commit 4565f0170dfc ("dma-mapping: unify
dma_get_cache_alignment implementations")
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Jeff Dike <jdike@addtoit.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
KOSAKI Motohiro [Thu, 19 Aug 2010 21:13:39 +0000 (14:13 -0700)]
oom: __task_cred() need rcu_read_lock()
dump_tasks() needs to hold the RCU read lock around its access of the
target task's UID. To this end it should use task_uid() as it only needs
that one thing from the creds.
The fact that dump_tasks() holds tasklist_lock is insufficient to prevent the
target process replacing its credentials on another CPU.
Then, this patch change to call rcu_read_lock() explicitly.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
KOSAKI Motohiro [Thu, 19 Aug 2010 21:13:39 +0000 (14:13 -0700)]
oom: fix tasklist_lock leak
Commit 0aad4b3124 ("oom: fold __out_of_memory into out_of_memory")
introduced a tasklist_lock leak. Then it caused following obvious
danger warnings and panic.
================================================
[ BUG: lock held when returning to user space! ]
------------------------------------------------
rsyslogd/1422 is leaving the kernel with locks still held!
1 lock held by rsyslogd/1422:
#0: (tasklist_lock){.+.+.+}, at: [<ffffffff810faf64>] out_of_memory+0x164/0x3f0
BUG: scheduling while atomic: rsyslogd/1422/0x00000002
INFO: lockdep is turned off.
This patch fixes it.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kyungmin Park [Thu, 19 Aug 2010 21:13:37 +0000 (14:13 -0700)]
drivers/mmc/host/sdhci-s3c.c: use the correct mutex and card detect function
There's some merge problem between sdhic core and sdhci-s3c host. After
mutex is changed to spinlock. It needs to use use spin lock functions and
use the correct card detection function.
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Cc: <linux-mmc@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Thu, 19 Aug 2010 21:13:33 +0000 (14:13 -0700)]
lib/radix-tree.c: fix overflow in radix_tree_range_tag_if_tagged()
When radix_tree_maxindex() is ~0UL, it can happen that scanning overflows
index and tree traversal code goes astray reading memory until it hits
unreadable memory. Check for overflow and exit in that case.
Signed-off-by: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@lst.de> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
: A second review after I've received a data sheet for this device from
: Fintek has turned up a few bugs.
:
: Unfortunately Giel (nor I) have time to fix this in time for the 2.6.36
: cycle. Therefor I would like to see this patch reverted as not having any
: support for the hwmon function of this superio chip is better then having
: unreliable support.
Cc: Giel van Schijndel <me@mortis.eu> Cc: Jean Delvare <khali@linux-fr.org> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ondrej Zary [Thu, 19 Aug 2010 21:13:25 +0000 (14:13 -0700)]
matroxfb: fix incorrect use of memcpy_toio()
Screen is completely corrupted since 2.6.34. Bisection revealed that it's
caused by commit 6175ddf06b61720 ("x86: Clean up mem*io functions.").
H. Peter Anvin explained that memcpy_toio() does not copy data in 32bit
chunks anymore on x86.
Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Petr Vandrovec <vandrove@vc.cvut.cz> Cc: Jean Delvare <khali@linux-fr.org> Cc: <stable@kernel.org> [2.6.34.x, 2.6.35.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Borislav Petkov [Thu, 19 Aug 2010 18:10:29 +0000 (20:10 +0200)]
x86, hotplug: Serialize CPU hotplug to avoid bringup concurrency issues
When testing cpu hotplug code on 32-bit we kept hitting the "CPU%d:
Stuck ??" message due to multiple cores concurrently accessing the
cpu_callin_mask, among others.
Since these codepaths are not protected from concurrent access due to
the fact that there's no sane reason for making an already complex
code unnecessarily more complex - we hit the issue only when insanely
switching cores off- and online - serialize hotplugging cores on the
sysfs level and be done with it.
[ v2.1: fix !HOTPLUG_CPU build ]
Cc: <stable@kernel.org> Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <20100819181029.GC17171@aftab> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Brian Norris [Wed, 18 Aug 2010 18:25:04 +0000 (11:25 -0700)]
mtd: nand: Fix regression in BBM detection
Commit c7b28e25cb9beb943aead770ff14551b55fa8c79 ("mtd: nand: refactor BB
marker detection") caused a regression in detection of factory-set bad
block markers, especially for certain small-page NAND. This fix removes
some unneeded constraints on using NAND_SMALL_BADBLOCK_POS, making the
detection code more correct.
This regression can be seen, for example, in Hynix HY27US081G1M and
similar.
Signed-off-by: Brian Norris <norris@broadcom.com> Tested-by: Michael Guntsche <mike@it-loops.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Linus Torvalds [Wed, 18 Aug 2010 22:45:23 +0000 (15:45 -0700)]
Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
NFS: Fix an Oops in the NFSv4 atomic open code
NFS: Fix the selection of security flavours in Kconfig
NFS: fix the return value of nfs_file_fsync()
rpcrdma: Fix SQ size calculation when memreg is FRMR
xprtrdma: Do not truncate iova_start values in frmr registrations.
nfs: Remove redundant NULL check upon kfree()
nfs: Add "lookupcache" to displayed mount options
NFS: allow close-to-open cache semantics to apply to root of NFS filesystem
SUNRPC: fix NFS client over TCP hangs due to packet loss (Bug 16494)
Linus Torvalds [Wed, 18 Aug 2010 22:29:38 +0000 (15:29 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
USB HID: Add ID for eGalax Multitouch used in JooJoo tablet
HID: hiddev: fix memory corruption due to invalid intfdata
HID: hiddev: protect against disconnect/NULL-dereference race
HID: picolcd: correct ordering of framebuffer freeing
HID: picolcd: testing the wrong variable
Jesse Barnes [Fri, 13 Aug 2010 22:11:26 +0000 (15:11 -0700)]
drm/i915: fix VGA plane disable for Ironlake+
We need to use I/O port instructions to access VGA registers on
Ironlake+, and it doesn't hurt on other platforms, so switch the VGA
plane disable function over to using them. Move it to init time as well
while we're at it, no need to repeatedly disable the VGA plane with
every mode set and DPMS event.
Jesse Barnes [Wed, 11 Aug 2010 17:06:44 +0000 (10:06 -0700)]
drm/i915: eDP mode set sequence corrections
We should disable the panel first when shutting down an eDP link. And
when turning one on, the panel needs to be enabled before link training
or eDP I/O won't be enabled.
Jesse Barnes [Wed, 11 Aug 2010 17:04:43 +0000 (10:04 -0700)]
drm/i915: add panel reset workaround
Ironlake requires that we clear the reset panel bit during power
sequences and restore it afterwards. Uncondtionally add code to do that
since it should be harmless on SNB+.
Missed the declaration of sys_execve in the ia64 asm/unistd.h (perhaps
because there is no reason for it to be there ... it might be a left over
from the COMPAT code?). Just delete the conflicting version.
Linus Torvalds [Wed, 18 Aug 2010 16:35:08 +0000 (09:35 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
fs: brlock vfsmount_lock
fs: scale files_lock
lglock: introduce special lglock and brlock spin locks
tty: fix fu_list abuse
fs: cleanup files_lock locking
fs: remove extra lookup in __lookup_hash
fs: fs_struct rwlock to spinlock
apparmor: use task path helpers
fs: dentry allocation consolidation
fs: fix do_lookup false negative
mbcache: Limit the maximum number of cache entries
hostfs ->follow_link() braino
hostfs: dumb (and usually harmless) tpyo - strncpy instead of strlcpy
remove SWRITE* I/O types
kill BH_Ordered flag
vfs: update ctime when changing the file's permission by setfacl
cramfs: only unlock new inodes
fix reiserfs_evict_inode end_writeback second call
Kusanagi Kouichi [Wed, 18 Aug 2010 16:32:37 +0000 (13:32 -0300)]
perf tools: Fix build error on read only source.
Parts of the build process were generating files outside the specified
O= directory, causing the build to fail on systems where the sources are
in a read only file system.
Fix it by using $(OUTPUT) on these locations.
Also check that $(OUTPUT) actually exists, just like the top level
kernel Makefile does. Otherwise the failure message emitted is
completely misleading.
Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20100817140841.0859362C03A@msa106.auone-net.jp> Signed-off-by: Kusanagi Kouichi <slash@ac.auone-net.jp> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linus Torvalds [Wed, 18 Aug 2010 16:32:13 +0000 (09:32 -0700)]
Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf tools: Fix build on POSIX shells
latencytop: Fix kconfig dependency warnings
perf annotate tui: Fix exit and RIGHT keys handling
tracing: Sanitize value returned from write(trace_marker, "...", len)
tracing/events: Convert format output to seq_file
tracing: Extend recordmcount to better support Blackfin mcount
tracing: Fix ring_buffer_read_page reading out of page boundary
tracing: Fix an unallocated memory access in function_graph
Linus Torvalds [Wed, 18 Aug 2010 16:27:10 +0000 (09:27 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68knommu: include sched.h in ColdFire/SPI driver
m68knommu: formatting of pointers in printk()
m68knommu: arch/m68k/include/asm/ide.h fix for nommu
Linus Torvalds [Wed, 18 Aug 2010 16:26:42 +0000 (09:26 -0700)]
Merge branch 'for-linus' of git://neil.brown.name/md
* 'for-linus' of git://neil.brown.name/md:
md raid-1/10 Fix bio_rw bit manipulations again
md: provide appropriate return value for spare_active functions.
md: Notify sysfs when RAID1/5/10 disk is In_sync.
Update recovery_offset even when external metadata is used.
Linus Torvalds [Wed, 18 Aug 2010 16:26:17 +0000 (09:26 -0700)]
Merge branch 'merge-devicetree' of git://git.secretlab.ca/git/linux-2.6
* 'merge-devicetree' of git://git.secretlab.ca/git/linux-2.6:
spi.h: missing kernel-doc notation, please fix
of: fix missing headers for of_address_to_resource() in MTD and SysACE drivers
of: Fix missing includes
ata: update for of_device to platform_device replacement
microblaze: Fix of: eliminate of_device->node and dev_archdata->{of,prom}_node
microblaze: Fix of/address: Merge all of the bus translation code
booting-without-of: Remove nonexistent chapters from TOC, fix numbering
Joerg Roedel [Mon, 16 Aug 2010 12:38:33 +0000 (14:38 +0200)]
x86-32: Separate 1:1 pagetables from swapper_pg_dir
This patch fixes machine crashes which occur when heavily exercising the
CPU hotplug codepaths on a 32-bit kernel. These crashes are caused by
AMD Erratum 383 and result in a fatal machine check exception. Here's
the scenario:
1. On 32-bit, the swapper_pg_dir page table is used as the initial page
table for booting a secondary CPU.
2. To make this work, swapper_pg_dir needs a direct mapping of physical
memory in it (the low mappings). By adding those low, large page (2M)
mappings (PAE kernel), we create the necessary conditions for Erratum
383 to occur.
3. Other CPUs which do not participate in the off- and onlining game may
use swapper_pg_dir while the low mappings are present (when leave_mm is
called). For all steps below, the CPU referred to is a CPU that is using
swapper_pg_dir, and not the CPU which is being onlined.
4. The presence of the low mappings in swapper_pg_dir can result
in TLB entries for addresses below __PAGE_OFFSET to be established
speculatively. These TLB entries are marked global and large.
5. When the CPU with such TLB entry switches to another page table, this
TLB entry remains because it is global.
6. The process then generates an access to an address covered by the
above TLB entry but there is a permission mismatch - the TLB entry
covers a large global page not accessible to userspace.
7. Due to this permission mismatch a new 4kb, user TLB entry gets
established. Further, Erratum 383 provides for a small window of time
where both TLB entries are present. This results in an uncorrectable
machine check exception signalling a TLB multimatch which panics the
machine.
There are two ways to fix this issue:
1. Always do a global TLB flush when a new cr3 is loaded and the
old page table was swapper_pg_dir. I consider this a hack hard
to understand and with performance implications
2. Do not use swapper_pg_dir to boot secondary CPUs like 64-bit
does.
This patch implements solution 2. It introduces a trampoline_pg_dir
which has the same layout as swapper_pg_dir with low_mappings. This page
table is used as the initial page table of the booting CPU. Later in the
bringup process, it switches to swapper_pg_dir and does a global TLB
flush. This fixes the crashes in our test cases.
-v2: switch to swapper_pg_dir right after entering start_secondary() so
that we are able to access percpu data which might not be mapped in the
trampoline page table.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
LKML-Reference: <20100816123833.GB28147@aftab> Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Hans Rosenfeld [Wed, 18 Aug 2010 14:19:50 +0000 (16:19 +0200)]
x86, cpu: Fix regression in AMD errata checking code
A bug in the family-model-stepping matching code caused the presence of
errata to go undetected when OSVW was not used. This causes hangs on
some K8 systems because the E400 workaround is not enabled.
Signed-off-by: Hans Rosenfeld <hans.rosenfeld@amd.com>
LKML-Reference: <1282141190-930137-1-git-send-email-hans.rosenfeld@amd.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Ryusuke Konishi [Wed, 18 Aug 2010 12:11:11 +0000 (21:11 +0900)]
nilfs2: wait for discard to finish
nilfs_discard_segment() doesn't wait for completion of discard
requests. This specifies BLKDEV_IFL_WAIT flag when calling
blkdev_issue_discard() in order to fix the sync failure.
Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Christoph Hellwig <hch@lst.de>
Jaroslav Kysela [Wed, 18 Aug 2010 12:08:17 +0000 (14:08 +0200)]
ALSA: emu10k1 - delay the PCM interrupts (add pcm_irq_delay parameter)
With some hardware combinations, the PCM interrupts are acknowledged
before the period boundary from the emu10k1 chip. The midlevel PCM code
gets confused and the playback stream is interrupted.
It seems that the interrupt processing shift by 2 samples is enough
to fix this issue. This default value does not harm other,
non-affected hardware.
More information: Kernel bugzilla bug#16300
[A copmile warning fixed by tiwai]
Signed-off-by: Jaroslav Kysela <perex@perex.cz> Cc: <stable@kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Nick Piggin [Tue, 17 Aug 2010 18:37:39 +0000 (04:37 +1000)]
fs: brlock vfsmount_lock
fs: brlock vfsmount_lock
Use a brlock for the vfsmount lock. It must be taken for write whenever
modifying the mount hash or associated fields, and may be taken for read when
performing mount hash lookups.
A new lock is added for the mnt-id allocator, so it doesn't need to take
the heavy vfsmount write-lock.
The number of atomics should remain the same for fastpath rlock cases, though
code would be slightly slower due to per-cpu access. Scalability is not not be
much improved in common cases yet, due to other locks (ie. dcache_lock) getting
in the way. However path lookups crossing mountpoints should be one case where
scalability is improved (currently requiring the global lock).
The slowpath is slower due to use of brlock. On a 64 core, 64 socket, 32 node
Altix system (high latency to remote nodes), a simple umount microbenchmark
(mount --bind mnt mnt2 ; umount mnt2 loop 1000 times), before this patch it
took 6.8s, afterwards took 7.1s, about 5% slower.
Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Nick Piggin [Tue, 17 Aug 2010 18:37:38 +0000 (04:37 +1000)]
fs: scale files_lock
fs: scale files_lock
Improve scalability of files_lock by adding per-cpu, per-sb files lists,
protected with an lglock. The lglock provides fast access to the per-cpu lists
to add and remove files. It also provides a snapshot of all the per-cpu lists
(although this is very slow).
One difficulty with this approach is that a file can be removed from the list
by another CPU. We must track which per-cpu list the file is on with a new
variale in the file struct (packed into a hole on 64-bit archs). Scalability
could suffer if files are frequently removed from different cpu's list.
However loads with frequent removal of files imply short interval between
adding and removing the files, and the scheduler attempts to avoid moving
processes too far away. Also, even in the case of cross-CPU removal, the
hardware has much more opportunity to parallelise cacheline transfers with N
cachelines than with 1.
A worst-case test of 1 CPU allocating files subsequently being freed by N CPUs
degenerates to contending on a single lock, which is no worse than before. When
more than one CPU are allocating files, even if they are always freed by
different CPUs, there will be more parallelism than the single-lock case.
Testing results:
On a 2 socket, 8 core opteron, I measure the number of times the lock is taken
to remove the file, the number of times it is removed by the same CPU that
added it, and the number of times it is removed by the same node that added it.
So a file is removed from the same CPU it was added by over 90% of the time.
It remains within the same node 95% of the time.
Tim Chen ran some numbers for a 64 thread Nehalem system performing a compile.
throughput
2.6.34-rc2 24.5
+patch 24.9
us sys idle IO wait (in %)
2.6.34-rc2 51.25 28.25 17.25 3.25
+patch 53.75 18.5 19 8.75
So significantly less CPU time spent in kernel code, higher idle time and
slightly higher throughput.
Single threaded performance difference was within the noise of microbenchmarks.
That is not to say penalty does not exist, the code is larger and more memory
accesses required so it will be slightly slower.
Cc: linux-kernel@vger.kernel.org Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Nick Piggin [Tue, 17 Aug 2010 18:37:37 +0000 (04:37 +1000)]
lglock: introduce special lglock and brlock spin locks
lglock: introduce special lglock and brlock spin locks
This patch introduces "local-global" locks (lglocks). These can be used to:
- Provide fast exclusive access to per-CPU data, with exclusive access to
another CPU's data allowed but possibly subject to contention, and to provide
very slow exclusive access to all per-CPU data.
- Or to provide very fast and scalable read serialisation, and to provide
very slow exclusive serialisation of data (not necessarily per-CPU data).
Brlocks are also implemented as a short-hand notation for the latter use
case.
Thanks to Paul for local/global naming convention.
Cc: linux-kernel@vger.kernel.org Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Nick Piggin [Tue, 17 Aug 2010 18:37:36 +0000 (04:37 +1000)]
tty: fix fu_list abuse
tty: fix fu_list abuse
tty code abuses fu_list, which causes a bug in remount,ro handling.
If a tty device node is opened on a filesystem, then the last link to the inode
removed, the filesystem will be allowed to be remounted readonly. This is
because fs_may_remount_ro does not find the 0 link tty inode on the file sb
list (because the tty code incorrectly removed it to use for its own purpose).
This can result in a filesystem with errors after it is marked "clean".
Taking idea from Christoph's initial patch, allocate a tty private struct
at file->private_data and put our required list fields in there, linking
file and tty. This makes tty nodes behave the same way as other device nodes
and avoid meddling with the vfs, and avoids this bug.
The error handling is not trivial in the tty code, so for this bugfix, I take
the simple approach of using __GFP_NOFAIL and don't worry about memory errors.
This is not a problem because our allocator doesn't fail small allocs as a rule
anyway. So proper error handling is left as an exercise for tty hackers.
[ Arguably filesystem's device inode would ideally be divorced from the
driver's pseudo inode when it is opened, but in practice it's not clear whether
that will ever be worth implementing. ]
Cc: linux-kernel@vger.kernel.org Cc: Christoph Hellwig <hch@infradead.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Nick Piggin [Tue, 17 Aug 2010 18:37:34 +0000 (04:37 +1000)]
fs: remove extra lookup in __lookup_hash
fs: remove extra lookup in __lookup_hash
Optimize lookup for create operations, where no dentry should often be
common-case. In cases where it is not, such as unlink, the added overhead
is much smaller than the removed.
Also, move comments about __d_lookup racyness to the __d_lookup call site.
d_lookup is intuitive; __d_lookup is what needs commenting. So in that same
vein, add kerneldoc comments to __d_lookup and clean up some of the comments:
- We are interested in how the RCU lookup works here, particularly with
renames. Make that explicit, and point to the document where it is explained
in more detail.
- RCU is pretty standard now, and macros make implementations pretty mindless.
If we want to know about RCU barrier details, we look in RCU code.
- Delete some boring legacy comments because we don't care much about how the
code used to work, more about the interesting parts of how it works now. So
comments about lazy LRU may be interesting, but would better be done in the
LRU or refcount management code.
Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Nick Piggin [Tue, 17 Aug 2010 18:37:33 +0000 (04:37 +1000)]
fs: fs_struct rwlock to spinlock
fs: fs_struct rwlock to spinlock
struct fs_struct.lock is an rwlock with the read-side used to protect root and
pwd members while taking references to them. Taking a reference to a path
typically requires just 2 atomic ops, so the critical section is very small.
Parallel read-side operations would have cacheline contention on the lock, the
dentry, and the vfsmount cachelines, so the rwlock is unlikely to ever give a
real parallelism increase.
Replace it with a spinlock to avoid one or two atomic operations in typical
path lookup fastpath.
Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Nick Piggin [Tue, 17 Aug 2010 18:37:30 +0000 (04:37 +1000)]
fs: fix do_lookup false negative
fs: fix do_lookup false negative
In do_lookup, if we initially find no dentry, we take the directory i_mutex and
re-check the lookup. If we find a dentry there, then we revalidate it if
needed. However if that revalidate asks for the dentry to be invalidated, we
return -ENOENT from do_lookup. What should happen instead is an attempt to
allocate and lookup a new dentry.
This is probably not noticed because it is rare. It is only reached if a
concurrent create races in first (in which case, the dentry probably won't be
invalidated anyway), or if the racy __d_lookup has failed due to a
false-negative (which is very rare).
Fix this by removing code and have it use the normal reval path.
Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Axel Lin [Mon, 16 Aug 2010 08:09:09 +0000 (16:09 +0800)]
pxa3xx: fix ns2cycle equation
Test on a PXA310 platform with Samsung K9F2G08X0B NAND flash,
with tCH=5 and clk is 156MHz, ns2cycle(5, 156000000) returns -1.
ns2cycle returns negtive value will break NDTR0_tXX macros.
After checking the commit log, I found the problem is introduced by
commit 5b0d4d7c8a67c5ba3d35e6ceb0c5530cc6846db7
"[MTD] [NAND] pxa3xx: convert from ns to clock ticks more accurately"
To get num of clock cycles, we use below equation:
num of clock cycles = time (ns) / one clock cycle (ns) + 1
We need to add 1 cycle here because integer division will truncate the result.
It is possible the developers set the Min values in SPEC for timing settings.
Thus the truncate may cause problem, and it is safe to add an extra cycle here.
The various fields in NDTR{01} are in units of clock ticks minus one,
thus we should subtract 1 cycle then.
Thus the correct equation should be:
num of clock cycles = time (ns) / one clock cycle (ns) + 1 - 1
= time (ns) / one clock cycle (ns)
Signed-off-by: Axel Lin <axel.lin@gmail.com> Signed-off-by: Lei Wen <leiwen@marvell.com> Acked-by: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Cc: stable@kernel.org
mbcache: Limit the maximum number of cache entries
Limit the maximum number of mb_cache entries depending on the number of
hash buckets: if the only limit to the number of cache entries is the
available memory the hash chains can grow very long, taking a long time
to search.
At least partially solves https://bugzilla.lustre.org/show_bug.cgi?id=22771.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
projects / linux-beck.git / log