1. 10 Sep, 2009 33 commits
  2. 09 Sep, 2009 3 commits
    • Linus Torvalds's avatar
      Linux 2.6.31 · 74fca6a4
      Linus Torvalds authored
      74fca6a4
    • Ed Cashin's avatar
      aoe: allocate unused request_queue for sysfs · 7135a71b
      Ed Cashin authored
      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
      
        cd43e26f
      
        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: default avatarEd 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: default avatarJens Axboe <jens.axboe@oracle.com>
      7135a71b
    • Linus Torvalds's avatar
      i915: disable interrupts before tearing down GEM state · e6890f6f
      Linus Torvalds authored
      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=13819Reported-and-tested-by: default avatarReinette Chatre <reinette.chatre@intel.com>
      Acked-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      e6890f6f
  3. 08 Sep, 2009 1 commit
  4. 07 Sep, 2009 3 commits