Hi,
On Thu, May 9, 2019 at 3:50 AM Giridhar Malavali <gmalavali@xxxxxxxxxxx> wrote:
>
>
>
> On 5/8/19, 1:42 PM, "linux-scsi-owner@xxxxxxxxxxxxxxx on behalf of Shivaram Upadhyayula" <linux-scsi-owner@xxxxxxxxxxxxxxx on behalf of shivaram.u@xxxxxxxxxxxx> wrote:
>
> Hi,
>
> There seem to be a few issues when trying to do a logout
> qla_target.c:qlt_free_session_done in 4.19.41
>
> 1. When the logout timesout qla2x00_sp_timeout is called. This
> function assumes sp->qpair is valid, but this isn't the case if mq is
> not enabled
With the upstream driver a sp->qpair is always valid, so the crash is
only specific to the 4.19.x driver
>
> 2. qla2x00_async_iocb_timeout also assumes that sp->qpair is valid.
> Also only if qla24xx_async_abort_cmd() fails is sp->done() called,
> sp->done in this case is qlt_logo_completion_handler() which will
> never be called if qla24xx_async_abort_cmd() succeeds
This is a problem with the upstream driver too. I haven't tried to
build this driver so my comments are based on my experience with
4.19.41.
In qla2x00_async_iocb_timeout, lets take the case of SRB_LOGOUT_CMD
switch (sp->type) {
..
case SRB_LOGOUT_CMD:
<...>
rc = qla24xx_async_abort_cmd(sp, false);
if (rc) {
....
sp->done(sp, QLA_FUNCTION_TIMEOUT);
}
sp->done() is called only if qla24xx_async_abort_cmd() fails (rc !=
0). The same for case SRB_LOGIN_CMD.
Regards,
Shivaram
> 3. qla24xx_async_abort_cmd() can lead to "scheduling while atomic" if
> called from qla2x00_async_iocb_timeout. The wait parameter can be used
> to alloc with GFP_ATOMIC
>
> Please see diff https://www.quadstor.com/patches/srb-logout.diff
> generated against 4.9.41
>
> >> We have addressed issues related to above in our latest upstream driver. Can you check and let us know whether you still see the above issues.
>
> -- Giri
>
> Regards,
> Shivaram
>
> --
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> https://www.quadstor.com/storage-virtualization.html
>
>
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