On Tue, 2019-12-10 at 12:57 -0500, Bart Van Assche wrote:
> On 12/10/19 6:47 AM, Martin Wilck wrote:
> > blk_mq_request_started() returns true for requests in
> > MQ_RQ_COMPLETE
> > state. Is this really an equivalent condition?
> >
> > That said, the condition in the current code is sort of strange, as
> > it's equivalent to !(sp->completed && sp->aborted). I'm wondering
> > what
> > it means if a command is both completed and aborted. Naïvely
> > thinking
> > (and inferring from the current code) this condition could never be
> > met, and thus its negation would hold for every command. Perhaps
> > Quinn
> > meant "!(sp->completed || sp->aborted)" ?
>
> Hi Martin,
>
> The only caller of qla2x00_abort_srb() is qla2x00_abort_all_cmds().
> That
> function should only be called after completion interrupts have been
> disabled. In other words, I don't think that we have to worry about
> blk_mq_request_started() encountering the MQ_RQ_COMPLETE state. No
> request should have that state when qla2x00_abort_all_cmds() is
> called.
I thought avoiding a race between completion and abort was the whole
point of f45bca8c5052 ("scsi: qla2xxx: Fix double scsi_done for abort
path"), which introduced the code that you're now changing. But I must
be overlooking something then, as Himanshu has acked this.
Martin
