<0000000000489812>] zfcp_fsf_req_send+0x166/0x180 [<000000000048c8d6>] zfcp_fsf_fcp_cmnd+0x272/0x408 [<000000000048f864>] zfcp_scsi_queuecommand+0x11c/0x1e0 [<00000000003f1f2a>] scsi_dispatch_cmd+0x1d6/0x324 [<00000000003f9910>] scsi_request_fn+0x42c/0x56c [<00000000003828ae>] __blk_run_queue+0x86/0x140 [<000000000037f742>] elv_insert+0x11a/0x208 [<000000000038104c>] blk_insert_cloned_request+0x84/0xe4 [<000003c0032b7c64>] dm_dispatch_request+0x6c/0x94 [dm_mod] [<000003c0032b7d5c>] map_request+0xd0/0x100 [dm_mod] [<000003c0032b9a78>] dm_request_fn+0xec/0x1bc [dm_mod] [<0000000000382c0e>] generic_unplug_device+0x5a/0x6c [<000003c0032b7f98>] dm_unplug_all+0x74/0x9c [dm_mod] [<00000000001d1272>] sync_page+0x76/0x9c [<00000000001d12ba>] sync_page_killable+0x22/0x60 [<000000000055a768>] __wait_on_bit_lock+0xc0/0x124 [<00000000001d1140>] __lock_page_killable+0x78/0x84 [<00000000001d351c>] generic_file_aio_read+0x5a4/0x7e8 [<0000000000228ec0>] do_sync_read+0xc8/0x12c [<0000000000229edc>] vfs_read+0xac/0x1ac [<000000000022a0d8>] SyS_read+0x58/0xa8 [<00000000001146de>] sysc_noemu+0x10/0x16 [<00000200000493c4>] 0x200000493c4 INFO: lockdep is turned off. Call zfcp_fsf_fcp_cmnd without the host_lock and disable the interrupts when acquiring the req_q_lock. According to the patch description in "[PATCH] Eliminate error handler overload of the SCSI serial number", the serial_number is not used, so simply drop the queuecommand wrapper function and run zfcp_scsi_queuecommand without holding the host_lock. Reviewed-by: Swen Schillig Signed-off-by: Christof Schmitt Signed-off-by: James Bottomley