On Wed, 2015-07-22 at 14:08 -0700, Dan Williams wrote: > On Wed, Jul 22, 2015 at 11:28 AM, James Bottomley > <james.bottom...@hansenpartnership.com> wrote: > > > >> } > >> > >> void sas_device_set_phy(struct domain_device *dev, struct sas_port *port) > >> diff --git a/drivers/scsi/libsas/sas_port.c > >> b/drivers/scsi/libsas/sas_port.c > >> index d3c5297c6c89..9a25ae3a52a4 100644 > >> --- a/drivers/scsi/libsas/sas_port.c > >> +++ b/drivers/scsi/libsas/sas_port.c > >> @@ -219,7 +219,6 @@ void sas_deform_port(struct asd_sas_phy *phy, int gone) > >> > >> if (port->num_phys == 1) { > >> sas_unregister_domain_devices(port, gone); > >> - sas_port_delete(port->port); > >> port->port = NULL; > >> } else { > >> sas_port_delete_phy(port->port, phy->phy); > >> > > > > This should become > > > > if (port->num_phys == 1) > > sas_unregister_domain_device(port, gone); > > > > sas_port_delete_phy(port->port, phy->phy); > > > > So we end up with a port scheduled for destruction with no phys rather > > than making the last phy association hang around until the DISCE > > workqueue runs. > > Sounds ok in theory.
It's not really a choice. The specific problem you've introduced with this patch is failure to cope with link flutter: a deform and form event queued sequentially. In the new scheme you're trying to introduce, the destruct event gets queued from the deform but behind the form and the link flutter results in a dead link. I thought just forcing a zero phy port would fix this, but it won't, either the destruct has to run in the context of the deform event or the form has to be queued later than the destruct. I think coupled with the changes above, there needs to be if (port->port) { /* dying port, requeue form event */ resend the PORTE_BYTES_DMAED event return } inside the unmatched port loop in sas_port_form() if nothing is found as well to close this. > I don't have a libsas environment handy, I worked with Praveen to > validate the version as submitted if you want to re-work it. A couple of days ago, this was so urgent as to have to go outside the usual patch process ... now it's not important enough for you to bother working on it; which is it? James -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html