1. 01 Oct, 2015 1 commit
    • Ming Lei's avatar
      blk-mq: fix buffer overflow when reading sysfs file of 'pending' · efa9b80e
      Ming Lei authored
      commit 596f5aad upstream.
      
      There may be lots of pending requests so that the buffer of PAGE_SIZE
      can't hold them at all.
      
      One typical example is scsi-mq, the queue depth(.can_queue) of
      scsi_host and blk-mq is quite big but scsi_device's queue_depth
      is a bit small(.cmd_per_lun), then it is quite easy to have lots
      of pending requests in hw queue.
      
      This patch fixes the following warning and the related memory
      destruction.
      
      [  359.025101] fill_read_buffer: blk_mq_hw_sysfs_show+0x0/0x7d returned bad count^M
      [  359.055595] irq event stamp: 15537^M
      [  359.055606] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC ^M
      [  359.055614] Dumping ftrace buffer:^M
      [  359.055660]    (ftrace buffer empty)^M
      [  359.055672] Modules linked in: nbd ipv6 kvm_intel kvm serio_raw^M
      [  359.055678] CPU: 4 PID: 21631 Comm: stress-ng-sysfs Not tainted 4.2.0-rc5-next-20150805 #434^M
      [  359.055679] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011^M
      [  359.055682] task: ffff8802161cc000 ti: ffff88021b4a8000 task.ti: ffff88021b4a8000^M
      [  359.055693] RIP: 0010:[<ffffffff811541c5>]  [<ffffffff811541c5>] __kmalloc+0xe8/0x152^M
      Signed-off-by: default avatarMing Lei <ming.lei@canonical.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      efa9b80e
  2. 21 Sep, 2015 31 commits
  3. 13 Sep, 2015 8 commits