On 06/02/2014 11:50 AM, Bart Van Assche wrote:
scsi_put_command() is either invoked before blk_start_request() or after block layer processing has completed. scsi_cmnd.abort_work is scheduled from inside the SCSI timeout handler. The block layer guarantees that either the regular completion handler (softirq_done_fn()) or the timeout handler (rq_timed_out_fn()) is invoked but not both. This means that scsi_put_command() is never invoked while abort_work is scheduled. Hence remove the cancel_delayed_work() call from scsi_put_command(). Similarly, scsi_abort_command() is only invoked from the SCSI timeout handler. If scsi_abort_command() is invoked for a SCSI command with the SCSI_EH_ABORT_SCHEDULED flag set this means that scmd_eh_abort_handler() has already invoked scsi_queue_insert() and hence that scsi_cmnd.abort_work is no longer pending. Hence also remove the cancel_delayed_work() call from scsi_abort_command(). Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx> Cc: Hannes Reinecke <hare@xxxxxxx> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: Jens Axboe <axboe@xxxxxx> Cc: Joe Lawrence <jdl1291@xxxxxxxxx> --- drivers/scsi/scsi.c | 2 +- drivers/scsi/scsi_error.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index 88d46fe..53b8b94 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -334,7 +334,7 @@ void scsi_put_command(struct scsi_cmnd *cmd) list_del_init(&cmd->list); spin_unlock_irqrestore(&cmd->device->list_lock, flags); - cancel_delayed_work(&cmd->abort_work); + BUG_ON(delayed_work_pending(&cmd->abort_work)); __scsi_put_command(cmd->device->host, cmd); } diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index f17aa7a..919ade2 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -193,7 +193,7 @@ scsi_abort_command(struct scsi_cmnd *scmd) SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd, "scmd %p previous abort failed\n", scmd)); - cancel_delayed_work(&scmd->abort_work); + BUG_ON(delayed_work_pending(&scmd->abort_work)); return FAILED; }
Reviewed-by: Hannes Reinecke <hare@xxxxxxx> Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@xxxxxxx +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
