1. 24 Oct, 2013 37 commits
  2. 23 Oct, 2013 3 commits
    • Aaron Lu's avatar
      [SCSI] sd: call blk_pm_runtime_init before add_disk · 10c580e4
      Aaron Lu authored
      Sujit has found a race condition that would make q->nr_pending
      unbalanced, it occurs as Sujit explained:
      
      "
      sd_probe_async() ->
      	add_disk() ->
      		disk_add_event() ->
      			schedule(disk_events_workfn)
      	sd_revalidate_disk()
      	blk_pm_runtime_init()
      return;
      
      Let's say the disk_events_workfn() calls sd_check_events() which tries
      to send test_unit_ready() and because of sd_revalidate_disk() trying to
      send another commands the test_unit_ready() might be re-queued as the
      tagged command queuing is disabled.
      
      So the race condition is -
      
      Thread 1 			  |		Thread 2
      sd_revalidate_disk()		  |	sd_check_events()
      ...nr_pending = 0 as q->dev = NULL|	scsi_queue_insert()
      blk_runtime_pm_init()		  | 	blk_pm_requeue_request() ->
      				  |	nr_pending = -1 since
      				  |	q->dev != NULL
      "
      
      The problem is, the test_unit_ready request doesn't get counted the
      first time it is queued, so the later decrement of q->nr_pending in
      blk_pm_requeue_request makes it unbalanced.
      
      Fix this by calling blk_pm_runtime_init before add_disk so that all
      requests initiated there will all be counted.
      Signed-off-by: default avatarAaron Lu <aaron.lu@intel.com>
      Reported-and-tested-by: default avatarSujit Reddy Thumma <sthumma@codeaurora.org>
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarJames Bottomley <JBottomley@Parallels.com>
      10c580e4
    • Chad Dupuis's avatar
      [SCSI] qla2xxx: Fix request queue null dereference. · 36008cf1
      Chad Dupuis authored
      If an invalid IOCB is returned on the response queue then the index into the
      request queue map could be invalid and could return to us a bogus value. This
      could cause us to try to deference an invalid pointer and cause an exception.
      
      If we encounter this condition, simply return as no context can be established
      for this response.
      Signed-off-by: default avatarChad Dupuis <chad.dupuis@qlogic.com>
      Signed-off-by: default avatarSaurav Kashyap <saurav.kashyap@qlogic.com>
      Signed-off-by: default avatarJames Bottomley <JBottomley@Parallels.com>
      36008cf1
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux · 320437af
      Linus Torvalds authored
      Pull s390 fixes from Martin Schwidefsky:
       "Several last minute bug fixes.
      
        Two of them are on the larger side for rc7, the dasd format patch for
        older storage devices and the store-clock-fast patch where we have
        been to optimistic with an optimization"
      
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
        s390/time: correct use of store clock fast
        s390/vmlogrdr: fix array access in vmlogrdr_open()
        s390/compat,signal: fix return value of copy_siginfo_(to|from)_user32()
        s390/dasd: check for availability of prefix command during format
        s390/mm,kvm: fix software dirty bits vs. kvm for old machines
      320437af