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  1. 15 Feb, 2011 15 commits
  3. 14 Feb, 2011 13 commits
  5. 13 Feb, 2011 6 commits
  7. 12 Feb, 2011 6 commits
    • Grant Likely's avatar
      MAINTAINERS: Add entry for GPIO subsystem · a0dc00b4
      Grant Likely authored 
      I'll probably regret this....
Signed-off-by: default avatarGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      a0dc00b4
    • Linus Torvalds's avatar
      Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 · c8e0b00e
      Linus Torvalds authored 
      * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd2: call __jbd2_log_start_commit with j_state_lock write locked
  ext4: serialize unaligned asynchronous DIO
  ext4: make grpinfo slab cache names static
  ext4: Fix data corruption with multi-block writepages support
  ext4: fix up ext4 error handling
  ext4: unregister features interface on module unload
  ext4: fix panic on module unload when stopping lazyinit thread
      c8e0b00e
    • Theodore Ts'o's avatar
      jbd2: call __jbd2_log_start_commit with j_state_lock write locked · e4471831
      Theodore Ts'o authored 
      On an SMP ARM system running ext4, I've received a report that the
first J_ASSERT in jbd2_journal_commit_transaction has been triggering:

	J_ASSERT(journal->j_running_transaction != NULL);

While investigating possible causes for this problem, I noticed that
__jbd2_log_start_commit() is getting called with j_state_lock only
read-locked, in spite of the fact that it's possible for it might
j_commit_request.  Fix this by grabbing the necessary information so
we can test to see if we need to start a new transaction before
dropping the read lock, and then calling jbd2_log_start_commit() which
will grab the write lock.
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
      e4471831
    • Eric Sandeen's avatar
      ext4: serialize unaligned asynchronous DIO · e9e3bcec
      Eric Sandeen authored 
      ext4 has a data corruption case when doing non-block-aligned
asynchronous direct IO into a sparse file, as demonstrated
by xfstest 240.

The root cause is that while ext4 preallocates space in the
hole, mappings of that space still look "new" and 
dio_zero_block() will zero out the unwritten portions.  When
more than one AIO thread is going, they both find this "new"
block and race to zero out their portion; this is uncoordinated
and causes data corruption.

Dave Chinner fixed this for xfs by simply serializing all
unaligned asynchronous direct IO.  I've done the same here.
The difference is that we only wait on conversions, not all IO.
This is a very big hammer, and I'm not very pleased with
stuffing this into ext4_file_write().  But since ext4 is
DIO_LOCKING, we need to serialize it at this high level.

I tried to move this into ext4_ext_direct_IO, but by then
we have the i_mutex already, and we will wait on the
work queue to do conversions - which must also take the
i_mutex.  So that won't work.

This was originally exposed by qemu-kvm installing to
a raw disk image with a normal sector-63 alignment.  I've
tested a backport of this patch with qemu, and it does
avoid the corruption.  It is also quite a lot slower
(14 min for package installs, vs. 8 min for well-aligned)
but I'll take slow correctness over fast corruption any day.

Mingming suggested that we can track outstanding
conversions, and wait on those so that non-sparse
files won't be affected, and I've implemented that here;
unaligned AIO to nonsparse files won't take a perf hit.

[tytso@mit.edu: Keep the mutex as a hashed array instead
 of bloating the ext4 inode]

[tytso@mit.edu: Fix up namespace issues so that global
 variables are protected with an "ext4_" prefix.]
Signed-off-by: default avatarEric Sandeen <sandeen@redhat.com>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
      e9e3bcec
    • Eric Sandeen's avatar
      ext4: make grpinfo slab cache names static · 2892c15d
      Eric Sandeen authored 
      In 2.6.37 I was running into oopses with repeated module
loads & unloads.  I tracked this down to:

fb1813f4 ext4: use dedicated slab caches for group_info structures

(this was in addition to the features advert unload problem)

The kstrdup & subsequent kfree of the cache name was causing
a double free.  In slub, at least, if I read it right it allocates
& frees the name itself, slab seems to do something different...
so in slub I think we were leaking -our- cachep->name, and double
freeing the one allocated by slub.

After getting lost in slab/slub/slob a bit, I just looked at other
sized-caches that get allocated.  jbd2, biovec, sgpool all do it
more or less the way jbd2 does.  Below patch follows the jbd2
method of dynamically allocating a cache at mount time from
a list of static names.

(This might also possibly fix a race creating the caches with
parallel mounts running).

[Folded in a fix from Dan Carpenter which fixed an off-by-one error in
the original patch]

Cc: stable@kernel.org
Signed-off-by: default avatarEric Sandeen <sandeen@redhat.com>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
      2892c15d
    • Kees Cook's avatar
      timer debug: Hide kernel addresses via %pK in /proc/timer_list · f5903085
      Kees Cook authored 
      In the continuing effort to avoid kernel addresses leaking to
unprivileged users, this patch switches to %pK for
/proc/timer_list reporting.
Signed-off-by: default avatarKees Cook <kees.cook@canonical.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: Eugene Teo <eugeneteo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20110212032125.GA23571@outflux.net>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      f5903085
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