Commit Graph

157330 Commits

Author SHA1 Message Date
Christoph Hellwig
d0800703fe xfs: stop calling filemap_fdatawait inside ->fsync
Now that the VFS actually waits for the data I/O to complete before
calling into ->fsync we can stop doing it ourselves.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-10-08 12:02:48 -05:00
Eric Sandeen
8e69ce1471 fix readahead calculations in xfs_dir2_leaf_getdents()
This is for bug #850,
http://oss.sgi.com/bugzilla/show_bug.cgi?id=850
XFS file system segfaults , repeatedly and 100% reproducable in 2.6.30 , 2.6.31

The above only showed up on a CONFIG_XFS_DEBUG=y kernel, because
xfs_bmapi() ASSERTs that it has been asked for at least one map,

and it was getting 0.

The root cause is that our guesstimated "bufsize" from xfs_file_readdir
was fairly small, and the

		bufsize -= length;

in the loop was going negative - except bufsize is a size_t, so it
was wrapping to a very large number.

Then when we did
		ra_want = howmany(bufsize + mp->m_dirblksize,
				  mp->m_sb.sb_blocksize) - 1;

with that very large number, the (int) ra_want was coming out
negative, and a subsequent compare:

		if (1 + ra_want > map_blocks ...

was coming out -true- (negative int compare w/ uint) and we went
back to xfs_bmapi() for more, even though we did not need more,
and asked for 0 maps, and hit the ASSERT.

We have kind of a type mess here, but just keeping bufsize from
going negative is probably sufficient to avoid the problem.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-10-08 12:02:12 -05:00
Dave Chinner
dce5065a57 xfs: make sure xfs_sync_fsdata covers the log
We want to always cover the log after writing out the superblock, and
in case of a synchronous writeout make sure we actually wait for the
log to be covered.  That way a filesystem that has been sync()ed can
be considered clean by log recovery.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-10-08 12:01:49 -05:00
Dave Chinner
932640e8ad xfs: mark inodes dirty before issuing I/O
To make sure they get properly waited on in sync when I/O is in flight and
we latter need to update the inode size.  Requires a new helper to check if an
ioend structure is beyond the current EOF.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-10-08 12:01:26 -05:00
Christoph Hellwig
69961a26b8 xfs: cleanup ->sync_fs
Sort out ->sync_fs to not perform a superblock writeback for the wait = 0 case
as that is just an optional first pass and the superblock will be written back
properly in the next call with wait = 1.  Instead perform an opportunistic
quota writeback to have less work later.  Also remove the freeze special case
as we do a proper wait = 1 call in the freeze code anyway.

Also rename the function to xfs_fs_sync_fs to match the normal naming
convention, update comments and avoid calling into the laptop_mode logic on
an error.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-10-08 12:01:03 -05:00
Dave Chinner
c90b07e8dd xfs: fix xfs_quiesce_data
We need to do a synchronous xfs_sync_fsdata to make sure the superblock
actually is on disk when we return.

Also remove SYNC_BDFLUSH flag to xfs_sync_inodes because that particular
flag is never checked.

Move xfs_filestream_flush call later to only release inodes after they
have been written out.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-10-08 12:00:36 -05:00
Christoph Hellwig
f9581b1443 xfs: implement ->dirty_inode to fix timestamp handling
This is picking up on Felix's repost of Dave's patch to implement a
.dirty_inode method.  We really need this notification because
the VFS keeps writing directly into the inode structure instead
of going through methods to update this state.  In addition to
the long-known atime issue we now also have a caller in VM code
that updates c/mtime that way for shared writeable mmaps.  And
I found another one that no one has noticed in practice in the FIFO
code.

So implement ->dirty_inode to set i_update_core whenever the
inode gets externally dirtied, and switch the c/mtime handling to
the same scheme we already use for atime (always picking up
the value from the Linux inode).

Note that this patch also removes the xfs_synchronize_atime call
in xfs_reclaim it was superflous as we already synchronize the time
when writing the inode via the log (xfs_inode_item_format) or the
normal buffers (xfs_iflush_int).

In addition also remove the I_CLEAR check before copying the Linux
timestamps - now that we always have the Linux inode available
we can always use the timestamps in it.

Also switch to just using file_update_time for regular reads/writes -
that will get us all optimization done to it for free and make
sure we notice early when it breaks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-10-08 12:00:03 -05:00
Jaswinder Singh Rajput
9ef96da6ec xfs: includecheck fix for fs/xfs/xfs_iops.c
fix the following 'make includecheck' warning:

  fs/xfs/linux-2.6/xfs_iops.c: xfs_acl.h is included more than once.

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-09-15 12:30:30 -05:00
Alexey Dobriyan
361735fd8f xfs: switch to seq_file
create_proc_read_entry() is getting deprecated.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-09-15 12:29:24 -05:00
Alex Elder
f08a59f146 xfs: Record new maintainer information
Update the MAINTAINERS file entry for XFS.

Signed-off-by: Alex Elder <aelder@sgi.com>
Signed-off by: Felix Blyakher <felixb@sgi.com>
2009-09-11 09:51:25 -05:00
Alex Elder
a4872d5b6a Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2009-09-10 14:33:56 -05:00
Christoph Hellwig
4734d401d4 xfs: use correct log reservation when handling ENOSPC in xfs_create
We added the ENOSPC handling patch in xfs_create just after it got mered
with xfs_mkdir.  Change the log reservation to the variable for either
the create or mkdir value so it does the right thing if get here for creating
a directory.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-09-09 18:19:02 -05:00
Linus Torvalds
74fca6a428 Linux 2.6.31 2009-09-09 15:13:59 -07:00
Ed Cashin
7135a71b19 aoe: allocate unused request_queue for sysfs
Andy Whitcroft reported an oops in aoe triggered by use of an
incorrectly initialised request_queue object:

  [ 2645.959090] kobject '<NULL>' (ffff880059ca22c0): tried to add
		an uninitialized object, something is seriously wrong.
  [ 2645.959104] Pid: 6, comm: events/0 Not tainted 2.6.31-5-generic #24-Ubuntu
  [ 2645.959107] Call Trace:
  [ 2645.959139] [<ffffffff8126ca2f>] kobject_add+0x5f/0x70
  [ 2645.959151] [<ffffffff8125b4ab>] blk_register_queue+0x8b/0xf0
  [ 2645.959155] [<ffffffff8126043f>] add_disk+0x8f/0x160
  [ 2645.959161] [<ffffffffa01673c4>] aoeblk_gdalloc+0x164/0x1c0 [aoe]

The request queue of an aoe device is not used but can be allocated in
code that does not sleep.

Bruno bisected this regression down to

  cd43e26f07

  block: Expose stacked device queues in sysfs

"This seems to generate /sys/block/$device/queue and its contents for
 everyone who is using queues, not just for those queues that have a
 non-NULL queue->request_fn."

Addresses http://bugs.launchpad.net/bugs/410198
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13942

Note that embedding a queue inside another object has always been
an illegal construct, since the queues are reference counted and
must persist until the last reference is dropped. So aoe was
always buggy in this respect (Jens).

Signed-off-by: Ed Cashin <ecashin@coraid.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Bruno Premont <bonbons@linux-vserver.org>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-09 14:10:18 +02:00
Linus Torvalds
e6890f6f3d i915: disable interrupts before tearing down GEM state
Reinette Chatre reports a frozen system (with blinking keyboard LEDs)
when switching from graphics mode to the text console, or when
suspending (which does the same thing). With netconsole, the oops
turned out to be

	BUG: unable to handle kernel NULL pointer dereference at 0000000000000084
	IP: [<ffffffffa03ecaab>] i915_driver_irq_handler+0x26b/0xd20 [i915]

and it's due to the i915_gem.c code doing drm_irq_uninstall() after
having done i915_gem_idle(). And the i915_gem_idle() path will do

  i915_gem_idle() ->
    i915_gem_cleanup_ringbuffer() ->
      i915_gem_cleanup_hws() ->
        dev_priv->hw_status_page = NULL;

but if an i915 interrupt comes in after this stage, it may want to
access that hw_status_page, and gets the above NULL pointer dereference.

And since the NULL pointer dereference happens from within an interrupt,
and with the screen still in graphics mode, the common end result is
simply a silently hung machine.

Fix it by simply uninstalling the irq handler before idling rather than
after. Fixes

    http://bugzilla.kernel.org/show_bug.cgi?id=13819

Reported-and-tested-by: Reinette Chatre <reinette.chatre@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-08 17:09:24 -07:00
Zhenyu Wang
7c8460db30 drm/i915: fix mask bits setting
eDP is exclusive connector too, and add missing crtc_mask
setting for TV.

This fixes

	http://bugzilla.kernel.org/show_bug.cgi?id=14139

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Reported-and-tested-by: Carlos R. Mafra <crmafra2@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-08 10:16:20 -07:00
Linus Torvalds
3ff323f890 Merge branch 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6
* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/radeon/kms: add LTE/GTE discard + rv515 two sided stencil register.
2009-09-07 11:42:25 -07:00
Linus Torvalds
755ae761c5 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: update ima_counts_put
2009-09-07 11:41:15 -07:00
Linus Torvalds
4886b5b485 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:
  gianfar: Fix build.
2009-09-07 11:40:24 -07:00
Linus Torvalds
cbeb2864b1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide-2.6:
  pcmcia: add CNF-CDROM-ID for ide
2009-09-07 11:40:15 -07:00
Linus Torvalds
f69fb9c398 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:
  agp/intel: support for new chip variant of IGDNG mobile
  drm/i915: Unref old_obj on get_fence_reg() error path
  drm/i915: increase default latency constant (v2 w/comment)
2009-09-07 11:38:30 -07:00
Dave Airlie
a54775c875 drm/radeon/kms: add LTE/GTE discard + rv515 two sided stencil register.
This adds some rv350+ register for LTE/GTE discard,
and enables the rv515 two sided stencil register.
It also disables the DEPTHXY_OFFSET register which
can be used to workaround the CS checker.
Moves rs690 to proper place in rs600 and uses correct
table on rs600.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2009-09-07 15:26:19 +10:00
Mimi Zohar
acd0c93517 IMA: update ima_counts_put
- As ima_counts_put() may be called after the inode has been freed,
verify that the inode is not NULL, before dereferencing it.

- Maintain the IMA file counters in may_open() properly, decrementing
any counter increments on subsequent errors.

Reported-by: Ciprian Docan <docan@eden.rutgers.edu>
Reported-by: J.R. Okajima <hooanon05@yahoo.co.jp>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com
Signed-off-by: James Morris <jmorris@namei.org>
2009-09-07 11:54:58 +10:00
David S. Miller
d9d8e0418f gianfar: Fix build.
Reported by Michael Guntsche <mike@it-loops.com>

--------------------
Commit
38bddf04bc gianfar: gfar_remove needs to call unregister_netdev()

breaks the build of the gianfar driver because "dev" is undefined in
this function. To quickly test rc9 I changed this to priv->ndev but I do
not know if this is the correct one.
--------------------

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-06 01:41:24 -07:00
Linus Torvalds
e07cccf404 Linux 2.6.31-rc9 2009-09-05 16:38:12 -07:00
Linus Torvalds
f815c335d2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: sbp2: fix freeing of unallocated memory
  firewire: ohci: fix Ricoh R5C832, video reception
  firewire: ohci: fix Agere FW643 and multiple cameras
  firewire: core: fix crash in iso resource management
2009-09-05 14:59:00 -07:00
Roderick Colenbrander
74a01180db powerpc: Fix i8259 interrupt driver kernel crash on ML510
This patch fixes a null pointer exception caused by removal of
'ack()' for level interrupts in the Xilinx interrupt driver.  A recent
change to the xilinx interrupt controller removed the ack hook for
level irqs.

Signed-off-by: Roderick Colenbrander <thunderbird2k@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-05 14:58:07 -07:00
Linus Torvalds
5136a6c0fd Merge git://git.infradead.org/~dwmw2/mtd-2.6.31
* git://git.infradead.org/~dwmw2/mtd-2.6.31:
  JFFS2: add missing verify buffer allocation/deallocation
  mtd: nftl: fix offset alignments
  mtd: nftl: write support is broken
  mtd: m25p80: fix null pointer dereference bug
2009-09-05 14:57:04 -07:00
Linus Torvalds
e505a8d5f9 Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  block: Allow changing max_sectors_kb above the default 512
2009-09-05 14:56:13 -07:00
Linus Torvalds
b71b7dc09a Merge branch 'fix/oxygen' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'fix/oxygen' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
  sound: oxygen: handle cards with missing EEPROM
  sound: oxygen: fix MCLK rate for 192 kHz playback
2009-09-05 14:55:30 -07:00
Linus Torvalds
59430c2f43 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:
  tc: Fix unitialized kernel memory leak
  pkt_sched: Revert tasklet_hrtimer changes.
  net: sk_free() should be allowed right after sk_alloc()
  gianfar: gfar_remove needs to call unregister_netdev()
  ipw2200: firmware DMA loading rework
2009-09-05 14:52:41 -07:00
Linus Torvalds
e9ee3a54a1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: skcipher - Fix skcipher_dequeue_givcrypt NULL test
2009-09-05 14:51:45 -07:00
Linus Torvalds
3bb314f01c Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] Re-enable cpufreq suspend and resume code
2009-09-05 14:51:24 -07:00
Linus Torvalds
535e0c1726 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
  [IA64] fix csum_ipv6_magic()
  [IA64] Fix warning in dma-mapping.c
2009-09-05 14:50:53 -07:00
Linus Torvalds
0edfa2b1b5 Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs
* 'for-linus' of git://oss.sgi.com/xfs/xfs:
  xfs: actually enable the swapext compat handler
2009-09-05 14:25:14 -07:00
Linus Torvalds
5a09adf130 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
  nilfs2: fix preempt count underflow in nilfs_btnode_prepare_change_key
2009-09-05 14:24:33 -07:00
Linus Torvalds
931f70350e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: don't assume existence of cpu0
2009-09-05 14:22:00 -07:00
Linus Torvalds
e305fc5ecd Merge branch 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6
* 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
  slub: Fix kmem_cache_destroy() with SLAB_DESTROY_BY_RCU
2009-09-05 13:57:53 -07:00
Linus Torvalds
154f807e55 Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
  dm snapshot: fix on disk chunk size validation
  dm exception store: split set_chunk_size
  dm snapshot: fix header corruption race on invalidation
  dm snapshot: refactor zero_disk_area to use chunk_io
  dm log: userspace add luid to distinguish between concurrent log instances
  dm raid1: do not allow log_failure variable to unset after being set
  dm log: remove incorrect field from userspace table output
  dm log: fix userspace status output
  dm stripe: expose correct io hints
  dm table: add more context to terse warning messages
  dm table: fix queue_limit checking device iterator
  dm snapshot: implement iterate devices
  dm multipath: fix oops when request based io fails when no paths
2009-09-05 13:51:07 -07:00
Linus Torvalds
9b6a3df372 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI SR-IOV: correct broken resource alignment calculations
2009-09-05 13:50:46 -07:00
Linus Torvalds
d3acd16cda Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc64: Fix bootup with mcount in some configs.
  sparc64: Kill spurious NMI watchdog triggers by increasing limit to 30 seconds.
2009-09-05 13:49:06 -07:00
Linus Torvalds
93697a3cab Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf_counter/powerpc: Fix cache event codes for POWER7
  perf_counter: Fix /0 bug in swcounters
  perf_counters: Increase paranoia level
2009-09-05 13:48:37 -07:00
Linus Torvalds
6399534472 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: atkbd - add Compaq Presario R4000-series repeat quirk
  Input: i8042 - add Acer Aspire 5536 to the nomux list
2009-09-05 13:41:29 -07:00
Nicolas Pitre
9de6886ec6 ext2: fix unbalanced kmap()/kunmap()
In ext2_rename(), dir_page is acquired through ext2_dotdot().  It is
then released through ext2_set_link() but only if old_dir != new_dir.
Failing that, the pkmap reference count is never decremented and the
page remains pinned forever.  Repeat that a couple times with highmem
pages and all pkmap slots get exhausted, and every further kmap() calls
end up stalling on the pkmap_map_wait queue at which point the whole
system comes to a halt.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Acked-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-05 13:41:08 -07:00
Linus Torvalds
ac7ac9f2b9 Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2:
  ocfs2: ocfs2_write_begin_nolock() should handle len=0
  ocfs2: invalidate dentry if its dentry_lock isn't initialized.
2009-09-05 13:38:37 -07:00
Linus Torvalds
ac89a9174d pty: don't limit the writes to 'pty_space()' inside 'pty_write()'
The whole write-room thing is something that is up to the _caller_ to
worry about, not the pty layer itself.  The total buffer space will
still be limited by the buffering routines themselves, so there is no
advantage or need in having pty_write() artificially limit the size
somehow.

And what happened was that the caller (the n_tty line discipline, in
this case) may have verified that there is room for 2 bytes to be
written (for NL -> CRNL expansion), and it used to then do those writes
as two single-byte writes.  And if the first byte written (CR) then
caused a new tty buffer to be allocated, pty_space() may have returned
zero when trying to write the second byte (LF), and then incorrectly
failed the write - leading to a lost newline character.

This should finally fix

	http://bugzilla.kernel.org/show_bug.cgi?id=14015

Reported-by: Mikael Pettersson <mikpe@it.uu.se>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-05 13:27:10 -07:00
Linus Torvalds
37f81fa1f6 n_tty: do O_ONLCR translation as a single write
When translating CR to CRNL in the n_tty line discipline, we did it as
two tty_put_char() calls.  Which works, but is stupid, and has caused
problems before too with bad interactions with the write_room() logic.
The generic USB serial driver had that problem, for example.

Now the pty layer had similar issues after being moved to the generic
tty buffering code (in commit d945cb9cce:
"pty: Rework the pty layer to use the normal buffering logic").

So stop doing the silly separate two writes, and do it as a single write
instead.  That's what the n_tty layer already does for the space
expansion of tabs (XTABS), and it means that we'll now always have just
a single write for the CRNL to match the single 'tty_write_room()' test,
which hopefully means that the next time somebody screws up buffering,
it won't cause weeks of debugging.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-05 12:46:07 -07:00
Oleg Nesterov
a2a8474c3f exec: do not sleep in TASK_TRACED under ->cred_guard_mutex
Tom Horsley reports that his debugger hangs when it tries to read
/proc/pid_of_tracee/maps, this happens since

	"mm_for_maps: take ->cred_guard_mutex to fix the race with exec"
	04b836cbf19e885f8366bccb2e4b0474346c02d

commit in 2.6.31.

But the root of the problem lies in the fact that do_execve() path calls
tracehook_report_exec() which can stop if the tracer sets PT_TRACE_EXEC.

The tracee must not sleep in TASK_TRACED holding this mutex.  Even if we
remove ->cred_guard_mutex from mm_for_maps() and proc_pid_attr_write(),
another task doing PTRACE_ATTACH should not hang until it is killed or the
tracee resumes.

With this patch do_execve() does not use ->cred_guard_mutex directly and
we do not hold it throughout, instead:

	- introduce prepare_bprm_creds() helper, it locks the mutex
	  and calls prepare_exec_creds() to initialize bprm->cred.

	- install_exec_creds() drops the mutex after commit_creds(),
	  and thus before tracehook_report_exec()->ptrace_stop().

	  or, if exec fails,

	  free_bprm() drops this mutex when bprm->cred != NULL which
	  indicates install_exec_creds() was not called.

Reported-by: Tom Horsley <tom.horsley@att.net>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-05 11:30:42 -07:00
Mel Gorman
dd5d241ea9 page-allocator: always change pageblock ownership when anti-fragmentation is disabled
On low-memory systems, anti-fragmentation gets disabled as fragmentation
cannot be avoided on a sufficiently large boundary to be worthwhile.  Once
disabled, there is a period of time when all the pageblocks are marked
MOVABLE and the expectation is that they get marked UNMOVABLE at each call
to __rmqueue_fallback().

However, when MAX_ORDER is large the pageblocks do not change ownership
because the normal criteria are not met.  This has the effect of
prematurely breaking up too many large contiguous blocks.  This is most
serious on NOMMU systems which depend on high-order allocations to boot.
This patch causes pageblocks to change ownership on every fallback when
anti-fragmentation is disabled.  This prevents the large blocks being
prematurely broken up.

This is a fix to commit 49255c619f [page
allocator: move check for disabled anti-fragmentation out of fastpath] and
the problem affects 2.6.31-rc8.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Tested-by: Paul Mundt <lethal@linux-sh.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-05 11:30:42 -07:00
David Howells
a190887b58 nommu: fix error handling in do_mmap_pgoff()
Fix the error handling in do_mmap_pgoff().  If do_mmap_shared_file() or
do_mmap_private() fail, we jump to the error_put_region label at which
point we cann __put_nommu_region() on the region - but we haven't yet
added the region to the tree, and so __put_nommu_region() may BUG
because the region tree is empty or it may corrupt the region tree.

To get around this, we can afford to add the region to the region tree
before calling do_mmap_shared_file() or do_mmap_private() as we keep
nommu_region_sem write-locked, so no-one can race with us by seeing a
transient region.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-05 11:30:42 -07:00