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  1. Oct 03, 2012
  3. Oct 01, 2012
  5. Sep 30, 2012
    • Miklos Szeredi's avatar
      vfs: dcache: fix deadlock in tree traversal · 8110e16d
      Miklos Szeredi authored 
      

IBM reported a deadlock in select_parent().  This was found to be caused
by taking rename_lock when already locked when restarting the tree
traversal.

There are two cases when the traversal needs to be restarted:

 1) concurrent d_move(); this can only happen when not already locked,
    since taking rename_lock protects against concurrent d_move().

 2) racing with final d_put() on child just at the moment of ascending
    to parent; rename_lock doesn't protect against this rare race, so it
    can happen when already locked.

Because of case 2, we need to be able to handle restarting the traversal
when rename_lock is already held.  This patch fixes all three callers of
try_to_ascend().

IBM reported that the deadlock is gone with this patch.

[ I rewrote the patch to be smaller and just do the "goto again" if the
  lock was already held, but credit goes to Miklos for the real work.
   - Linus ]

Signed-off-by: default avatarMiklos Szeredi <mszeredi@suse.cz>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      8110e16d
    • Linus Torvalds's avatar
      Merge tag 'iommu-fixes-v3.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu · 6a3e3dbe
      Linus Torvalds authored 
      Pull IOMMU fixes from Joerg Roedel:
 "Two small patches:

	* One patch to fix the function declarations for
	  !CONFIG_IOMMU_API. This is causing build errors
	  in linux-next and should be fixed for v3.6.

	* Another patch to fix an IOMMU group related NULL pointer
	  dereference."

* tag 'iommu-fixes-v3.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/amd: Fix wrong assumption in iommu-group specific code
  iommu: static inline iommu group stub functions
      6a3e3dbe
    • Linus Torvalds's avatar
      Merge git://git.infradead.org/users/willy/linux-nvme · 21e98932
      Linus Torvalds authored 
      Pull NVMe driver fixes from Matthew Wilcox:
 "Now that actual hardware has been released (don't have any yet
  myself), people are starting to want some of these fixes merged."

Willy doesn't have hardware? Guys...

* git://git.infradead.org/users/willy/linux-nvme:
  NVMe: Cancel outstanding IOs on queue deletion
  NVMe: Free admin queue memory on initialisation failure
  NVMe: Use ida for nvme device instance
  NVMe: Fix whitespace damage in nvme_init
  NVMe: handle allocation failure in nvme_map_user_pages()
  NVMe: Fix uninitialized iod compiler warning
  NVMe: Do not set IO queue depth beyond device max
  NVMe: Set block queue max sectors
  NVMe: use namespace id for nvme_get_features
  NVMe: replace nvme_ns with nvme_dev for user admin
  NVMe: Fix nvme module init when nvme_major is set
  NVMe: Set request queue logical block size
      21e98932
  7. Sep 29, 2012
    • Linus Torvalds's avatar
      mtdchar: fix offset overflow detection · 9c603e53
      Linus Torvalds authored 
      

Sasha Levin has been running trinity in a KVM tools guest, and was able
to trigger the BUG_ON() at arch/x86/mm/pat.c:279 (verifying the range of
the memory type).  The call trace showed that it was mtdchar_mmap() that
created an invalid remap_pfn_range().

The problem is that mtdchar_mmap() does various really odd and subtle
things with the vma page offset etc, and uses the wrong types (and the
wrong overflow) detection for it.

For example, the page offset may well be 32-bit on a 32-bit
architecture, but after shifting it up by PAGE_SHIFT, we need to use a
potentially 64-bit resource_size_t to correctly hold the full value.

Also, we need to check that the vma length plus offset doesn't overflow
before we check that it is smaller than the length of the mtdmap region.

This fixes things up and tries to make the code a bit easier to read.

Reported-and-tested-by: default avatarSasha Levin <levinsasha928@gmail.com>
Acked-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
Acked-by: default avatarArtem Bityutskiy <dedekind1@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      9c603e53