Re: iSCSI target: Handling in-flight requests during ctld shutdown

On 31.12.2021 17:17, John Baldwin wrote:
> So my remaining question I guess is if I add a new
> 'cs->cs_terminating_tasks'
> or the like, how does cfiscsi_datamove_out ensure that no response is sent?

By the time cs_terminating_tasks is set, there is no connection any
more, so nothing will be sent any way.  The problem with cs_terminating
is that it is set too early, when connection may still be alive.

On top of that, probably not important, but CTL_TASK_I_T_NEXUS_RESET
call by cfiscsi_session_terminate_tasks() will make the code below to
also block the status reporting for the most commands.

> The only thing I've seen so far is this code in cfiscsi_scsi_command_done:
> 
>     /*
>      * Do not return status for aborted commands.
>      * There are exceptions, but none supported by CTL yet.
>      */
>     if (((io->io_hdr.flags & CTL_FLAG_ABORT) &&
>          (io->io_hdr.flags & CTL_FLAG_ABORT_STATUS) == 0) ||
>         (io->io_hdr.flags & CTL_FLAG_STATUS_SENT)) {
>         ctl_free_io(io);
>         icl_pdu_free(request);
>         return;
>     }
> 
> Would you prefer checking cs_terminating_tasks in this function as well to
> avoid sending the peudo-aborted responses instead of forcing CTL_FLAG_ABORT
> on?

CTL_FLAG_ABORT flags there are correct.  The tasks are really aborted.
But if I remember it right, CTL_TASK_I_T_NEXUS_RESET should not set
CTL_FLAG_ABORT_STATUS, so abort statuses should not be sent.  Abort
statuses are only sent when initiator does not expect aborts, for
example, when some other initiator requested LUN or target reset.

-- 
Alexander Motin