On 12/22/14 19:49, Mike Snitzer wrote: > On Mon, Dec 22 2014 at 10:28am -0500, > Bart Van Assche <bvanassche@xxxxxxx> wrote: >> Good news: with this patch my standard SRP multipath test ran fine for >> several hours, after which I stopped the test. > > Great, thanks for testing! Did you happen to look at the performance of > your testing? If so, is it comparable/better/worse? Hello Mike, I have tried to run a performance comparison but after I had finished the measurements without multipath and when I started multipathd I ran into the following (typed over from the console): BUG: unable to handle kernel NULL pointer dereference at 0000318 IP: scsi_setup_cmnd+0xe8 [scsi_mod] Workqueue: kblockd blk_mq_run_work_fn Call Trace: scsi_queue_rq+0x5a5 __blk_mq_run_hw_queue+0x1cb blk_mq_run_work_fn+0xd process_one_work+0x133 worker_thread+0x11b kthread+0xcd gdb translates the above address as follows: (gdb) list *(scsi_setup_cmnd+0xe8) 0x9568 is in scsi_setup_cmnd (include/scsi/scsi_cmnd.h:155). 150 } 151 152 /* make sure not to use it with REQ_TYPE_BLOCK_PC commands */ 153 static inline struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) 154 { 155 return *(struct scsi_driver **)cmd->request->rq_disk->private_data; 156 } 157 158 extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, gfp_t); 159 extern void scsi_put_command(struct scsi_cmnd *); Bart. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel