On Mon, 2014-05-26 at 17:23 +0200, Paolo Bonzini wrote: > Il 26/05/2014 17:14, Bart Van Assche ha scritto: > > scsi_put_command() is either invoked before a command is queued or > > after a command has completed. scsi_cmnd.abort_work is scheduled > > after a command has timed out and before it is finished. The block > > layer guarantees that either the softirq_done_fn() or the > > rq_timed_out_fn() function 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 <joe.lawrence@xxxxxxxxxxx> > > --- > > 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..c972eab 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); > > + WARN_ON_ONCE(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..5232583 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); > > + WARN_ON_ONCE(delayed_work_pending(&scmd->abort_work)); > > return FAILED; > > } > > > > > > I still prefer a BUG_ON in scsi_put_command, but anyway: series Me too, since this is supposed to be an impossible condition that would induce corruption in the cmd free lists and hence make the system unusable. James -- 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
