[dm-devel] [PATCH] scsi_dh: check queuedata pointer before proceeding further

[Hannes Reinecke]

On 10/26/2011 08:29 PM, Moger, Babu wrote:
> This patch validates sdev pointer in scsi_dh_activate before proceeding further.
> 
> Without this check we might see the panic as below. I have seen this
> panic multiple times..
> 
> Call trace:
> 
>  #0 [ffff88007d647b50] machine_kexec at ffffffff81020902
>  #1 [ffff88007d647ba0] crash_kexec at ffffffff810875b0
>  #2 [ffff88007d647c70] oops_end at ffffffff8139c650
>  #3 [ffff88007d647c90] __bad_area_nosemaphore at ffffffff8102dd15
>  #4 [ffff88007d647d50] page_fault at ffffffff8139b8cf
>     [exception RIP: scsi_dh_activate+0x82]
>     RIP: ffffffffa0041922  RSP: ffff88007d647e00  RFLAGS: 00010046
>     RAX: 0000000000000000  RBX: 0000000000000000  RCX: 00000000000093c5
>     RDX: 00000000000093c5  RSI: ffffffffa02e6640  RDI: ffff88007cc88988
>     RBP: 000000000000000f   R8: ffff88007d646000   R9: 0000000000000000
>     R10: ffff880082293790  R11: 00000000ffffffff  R12: ffff88007cc88988
>     R13: 0000000000000000  R14: 0000000000000286  R15: ffff880037b845e0
>     ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
>  #5 [ffff88007d647e38] run_workqueue at ffffffff81060268
>  #6 [ffff88007d647e78] worker_thread at ffffffff81060386
>  #7 [ffff88007d647ee8] kthread at ffffffff81064436
>  #8 [ffff88007d647f48] kernel_thread at ffffffff81003fba
> 
> Signed-off-by: Babu Moger <babu.moger at netapp.com>
Acked-by: Hannes Reinecke <hare at suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke              zSeries & Storage
hare at suse.de                  +49 911 74053 688
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