Ping on this -- Tejun, Brian, Jeff, this is a pretty annoying 2.6.39 regression which it would be good to have fixed in 3.0. Thanks, Nish On 16.06.2011 [08:28:36 -0700], Nishanth Aravamudan wrote: > On 16.06.2011 [08:28:39 -0500], Brian King wrote: > > On 06/16/2011 02:51 AM, Tejun Heo wrote: > > > On Wed, Jun 15, 2011 at 04:34:17PM -0700, Nishanth Aravamudan wrote: > > >>> That looks like the right thing to do. For ipr's usage of > > >>> libata, we don't have the concept of a port frozen state, so this flag > > >>> should really never get set. The alternate way to fix this would be to > > >>> only set ATA_PFLAG_FROZEN in ata_port_alloc if ap->ops->error_handler > > >>> is not NULL. > > >> > > >> It seemed like ipr is as you say, but I wasn't sure if it was > > >> appropriate to make the change above in the common libata-scis code or > > >> not. I don't want to break some other device on accident. > > >> > > >> Also, I tried your suggestion, but I don't think that can happen in > > >> ata_port_alloc? ata_port_alloc is allocated ap itself, and it seems like > > >> ap->ops typically gets set only after ata_port_alloc returns? > > > > > > Maybe we can test error_handler in ata_sas_port_start()? > > > > Good point. Since libsas is converted to the new eh now, we would need to have > > this test. > > Commit 7b3a24c57d2eeda8dba9c205342b12689c4679f9 ("ahci: don't enable > port irq before handler is registered") caused a regression for CD-ROMs > attached to the IPR SATA bus on Power machines: > > ata_port_alloc: ENTER > ata_port_probe: ata1: bus probe begin > ata1.00: ata_dev_read_id: ENTER > ata1.00: failed to IDENTIFY (I/O error, err_mask=0x40) > ata1.00: ata_dev_read_id: ENTER > ata1.00: failed to IDENTIFY (I/O error, err_mask=0x40) > ata1.00: limiting speed to UDMA7:PIO5 > ata1.00: ata_dev_read_id: ENTER > ata1.00: failed to IDENTIFY (I/O error, err_mask=0x40) > ata1.00: disabled > ata_port_probe: ata1: bus probe end > scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured > > The FROZEN flag added in that commit is only cleared by the new EH code, > which is not used by ipr. Clear this flag in the SAS code if we don't > support new EH. > > Reported-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> > Signed-off-by: Nishanth Aravamudan <nacc@xxxxxxxxxx> > > diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c > index d51f979..ebe1685 100644 > --- a/drivers/ata/libata-scsi.c > +++ b/drivers/ata/libata-scsi.c > @@ -3797,6 +3797,12 @@ EXPORT_SYMBOL_GPL(ata_sas_port_alloc); > */ > int ata_sas_port_start(struct ata_port *ap) > { > + /* > + * the port is marked as frozen at allocation time, but if we don't > + * have new eh, we won't thaw it > + */ > + if (!ap->ops->error_handler) > + ap->pflags &= ~ATA_PFLAG_FROZEN; > return 0; > } > EXPORT_SYMBOL_GPL(ata_sas_port_start); > > > -- > Nishanth Aravamudan <nacc@xxxxxxxxxx> > IBM Linux Technology Center -- Nishanth Aravamudan <nacc@xxxxxxxxxx> IBM Linux Technology Center -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html