1. 15 Mar, 2014 37 commits
  2. 12 Mar, 2014 1 commit
  3. 10 Mar, 2014 2 commits
    • Giridhar Malavali's avatar
    • Lukasz Dorau's avatar
      [SCSI] isci: correct erroneous for_each_isci_host macro · c59053a2
      Lukasz Dorau authored
      In the first place, the loop 'for' in the macro 'for_each_isci_host'
      (drivers/scsi/isci/host.h:314) is incorrect, because it accesses
      the 3rd element of 2 element array. After the 2nd iteration it executes
      the instruction:
              ihost = to_pci_info(pdev)->hosts[2]
      (while the size of the 'hosts' array equals 2) and reads an
      out of range element.
      
      In the second place, this loop is incorrectly optimized by GCC v4.8
      (see http://marc.info/?l=linux-kernel&m=138998871911336&w=2).
      As a result, on platforms with two SCU controllers,
      the loop is executed more times than it can be (for i=0,1 and 2).
      It causes kernel panic during entering the S3 state
      and the following oops after 'rmmod isci':
      
      BUG: unable to handle kernel NULL pointer dereference at (null)
      IP: [<ffffffff8131360b>] __list_add+0x1b/0xc0
      Oops: 0000 [#1] SMP
      RIP: 0010:[<ffffffff8131360b>]  [<ffffffff8131360b>] __list_add+0x1b/0xc0
      Call Trace:
        [<ffffffff81661b84>] __mutex_lock_slowpath+0x114/0x1b0
        [<ffffffff81661c3f>] mutex_lock+0x1f/0x30
        [<ffffffffa03e97cb>] sas_disable_events+0x1b/0x50 [libsas]
        [<ffffffffa03e9818>] sas_unregister_ha+0x18/0x60 [libsas]
        [<ffffffffa040316e>] isci_unregister+0x1e/0x40 [isci]
        [<ffffffffa0403efd>] isci_pci_remove+0x5d/0x100 [isci]
        [<ffffffff813391cb>] pci_device_remove+0x3b/0xb0
        [<ffffffff813fbf7f>] __device_release_driver+0x7f/0xf0
        [<ffffffff813fc8f8>] driver_detach+0xa8/0xb0
        [<ffffffff813fbb8b>] bus_remove_driver+0x9b/0x120
        [<ffffffff813fcf2c>] driver_unregister+0x2c/0x50
        [<ffffffff813381f3>] pci_unregister_driver+0x23/0x80
        [<ffffffffa04152f8>] isci_exit+0x10/0x1e [isci]
        [<ffffffff810d199b>] SyS_delete_module+0x16b/0x2d0
        [<ffffffff81012a21>] ? do_notify_resume+0x61/0xa0
        [<ffffffff8166ce29>] system_call_fastpath+0x16/0x1b
      
      The loop has been corrected.
      This patch fixes kernel panic during entering the S3 state
      and the above oops.
      Signed-off-by: default avatarLukasz Dorau <lukasz.dorau@intel.com>
      Reviewed-by: default avatarMaciej Patelczyk <maciej.patelczyk@intel.com>
      Tested-by: default avatarLukasz Dorau <lukasz.dorau@intel.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
      Signed-off-by: default avatarJames Bottomley <JBottomley@Parallels.com>
      c59053a2