1. 17 1月, 2012 20 次提交
  2. 18 11月, 2011 1 次提交
    • K
      pstore: pass allocated memory region back to caller · f6f82851
      Kees Cook 提交于
      The buf_lock cannot be held while populating the inodes, so make the backend
      pass forward an allocated and filled buffer instead. This solves the following
      backtrace. The effect is that "buf" is only ever used to notify the backends
      that something was written to it, and shouldn't be used in the read path.
      
      To replace the buf_lock during the read path, isolate the open/read/close
      loop with a separate mutex to maintain serialized access to the backend.
      
      Note that is is up to the pstore backend to cope if the (*write)() path is
      called in the middle of the read path.
      
      [   59.691019] BUG: sleeping function called from invalid context at .../mm/slub.c:847
      [   59.691019] in_atomic(): 0, irqs_disabled(): 1, pid: 1819, name: mount
      [   59.691019] Pid: 1819, comm: mount Not tainted 3.0.8 #1
      [   59.691019] Call Trace:
      [   59.691019]  [<810252d5>] __might_sleep+0xc3/0xca
      [   59.691019]  [<810a26e6>] kmem_cache_alloc+0x32/0xf3
      [   59.691019]  [<810b53ac>] ? __d_lookup_rcu+0x6f/0xf4
      [   59.691019]  [<810b68b1>] alloc_inode+0x2a/0x64
      [   59.691019]  [<810b6903>] new_inode+0x18/0x43
      [   59.691019]  [<81142447>] pstore_get_inode.isra.1+0x11/0x98
      [   59.691019]  [<81142623>] pstore_mkfile+0xae/0x26f
      [   59.691019]  [<810a2a66>] ? kmem_cache_free+0x19/0xb1
      [   59.691019]  [<8116c821>] ? ida_get_new_above+0x140/0x158
      [   59.691019]  [<811708ea>] ? __init_rwsem+0x1e/0x2c
      [   59.691019]  [<810b67e8>] ? inode_init_always+0x111/0x1b0
      [   59.691019]  [<8102127e>] ? should_resched+0xd/0x27
      [   59.691019]  [<8137977f>] ? _cond_resched+0xd/0x21
      [   59.691019]  [<81142abf>] pstore_get_records+0x52/0xa7
      [   59.691019]  [<8114254b>] pstore_fill_super+0x7d/0x91
      [   59.691019]  [<810a7ff5>] mount_single+0x46/0x82
      [   59.691019]  [<8114231a>] pstore_mount+0x15/0x17
      [   59.691019]  [<811424ce>] ? pstore_get_inode.isra.1+0x98/0x98
      [   59.691019]  [<810a8199>] mount_fs+0x5a/0x12d
      [   59.691019]  [<810b9174>] ? alloc_vfsmnt+0xa4/0x14a
      [   59.691019]  [<810b9474>] vfs_kern_mount+0x4f/0x7d
      [   59.691019]  [<810b9d7e>] do_kern_mount+0x34/0xb2
      [   59.691019]  [<810bb15f>] do_mount+0x5fc/0x64a
      [   59.691019]  [<810912fb>] ? strndup_user+0x2e/0x3f
      [   59.691019]  [<810bb3cb>] sys_mount+0x66/0x99
      [   59.691019]  [<8137b537>] sysenter_do_call+0x12/0x26
      Signed-off-by: NKees Cook <keescook@chromium.org>
      Signed-off-by: NTony Luck <tony.luck@intel.com>
      f6f82851
  3. 13 11月, 2011 1 次提交
  4. 07 11月, 2011 8 次提交
  5. 05 11月, 2011 1 次提交
  6. 01 11月, 2011 4 次提交
  7. 22 10月, 2011 1 次提交
  8. 17 10月, 2011 2 次提交
  9. 15 10月, 2011 1 次提交
    • P
      PCI hotplug: acpiphp: Prevent deadlock on PCI-to-PCI bridge remove · 6af8bef1
      Prarit Bhargava 提交于
      I originally submitted a patch to workaround this by pushing all Ejection
      Requests and Device Checks onto the kacpi_hotplug queue.
      
      http://marc.info/?l=linux-acpi&m=131678270930105&w=2
      
      The patch is still insufficient in that Bus Checks also need to be added.
      
      Rather than add all events, including non-PCI-hotplug events, to the
      hotplug queue, mjg suggested that a better approach would be to modify
      the acpiphp driver so only acpiphp events would be added to the
      kacpi_hotplug queue.
      
      It's a longer patch, but at least we maintain the benefit of having separate
      queues in ACPI.  This, of course, is still only a workaround the problem.
      As Bjorn and mjg pointed out, we have to refactor a lot of this code to do
      the right thing but at this point it is a better to have this code working.
      
      The acpi core places all events on the kacpi_notify queue.  When the acpiphp
      driver is loaded and a PCI card with a PCI-to-PCI bridge is removed the
      following call sequence occurs:
      
      cleanup_p2p_bridge()
      	    -> cleanup_bridge()
      		    -> acpi_remove_notify_handler()
      			    -> acpi_os_wait_events_complete()
      				    -> flush_workqueue(kacpi_notify_wq)
      
      which is the queue we are currently executing on and the process will hang.
      
      Move all hotplug acpiphp events onto the kacpi_hotplug workqueue.  In
      handle_hotplug_event_bridge() and handle_hotplug_event_func() we can simply
      push the rest of the work onto the kacpi_hotplug queue and then avoid the
      deadlock.
      Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
      Cc: mjg@redhat.com
      Cc: bhelgaas@google.com
      Cc: linux-acpi@vger.kernel.org
      Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      6af8bef1
  10. 13 10月, 2011 1 次提交