| Message ID | 4D00F20B.2080908@kernel.org |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
On 12/09/2010 10:13 AM, Tejun Heo wrote: > Low level drivers may behave differently depending on the current > link->lpm_policy. During ata_eh_set_lpm(), DIPM enable commands are > issued after the successful completion of ap->ops->set_lpm(), which > means that the controller is already in the target state. This causes > DIPM enable commands to be processed with mismatching controller power > state and link->lpm_policy value. > > In ahci, link->lpm_policy is used to ignore certain PHY events if LPM > is enabled; however, as DIPM commands are issued with stale > link->lpm_policy, they sometimes end up triggering these conditions > and get aborted leading to LPM configuration failure. > > Fix it by updating link->lpm_policy before issuing DIPM enable > commands. > > Signed-off-by: Tejun Heo<tj@kernel.org> > Reported-by: Kyle McMartin<kyle@mcmartin.ca> > Cc: stable@kernel.org > --- > drivers/ata/libata-eh.c | 17 ++++++++++++++--- > 1 file changed, 14 insertions(+), 3 deletions(-) applied -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index 5e59050..17a6378 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -3275,6 +3275,7 @@ static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy, struct ata_port *ap = ata_is_host_link(link) ? link->ap : NULL; struct ata_eh_context *ehc = &link->eh_context; struct ata_device *dev, *link_dev = NULL, *lpm_dev = NULL; + enum ata_lpm_policy old_policy = link->lpm_policy; unsigned int hints = ATA_LPM_EMPTY | ATA_LPM_HIPM; unsigned int err_mask; int rc; @@ -3338,6 +3339,14 @@ static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy, goto fail; } + /* + * Low level driver acked the transition. Issue DIPM command + * with the new policy set. + */ + link->lpm_policy = policy; + if (ap && ap->slave_link) + ap->slave_link->lpm_policy = policy; + /* host config updated, enable DIPM if transitioning to MIN_POWER */ ata_for_each_dev(dev, link, ENABLED) { if (policy == ATA_LPM_MIN_POWER && ata_id_has_dipm(dev->id)) { @@ -3353,12 +3362,14 @@ static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy, } } - link->lpm_policy = policy; - if (ap && ap->slave_link) - ap->slave_link->lpm_policy = policy; return 0; fail: + /* restore the old policy */ + link->lpm_policy = old_policy; + if (ap && ap->slave_link) + ap->slave_link->lpm_policy = old_policy; + /* if no device or only one more chance is left, disable LPM */ if (!dev || ehc->tries[dev->devno] <= 2) { ata_link_printk(link, KERN_WARNING,
Low level drivers may behave differently depending on the current link->lpm_policy. During ata_eh_set_lpm(), DIPM enable commands are issued after the successful completion of ap->ops->set_lpm(), which means that the controller is already in the target state. This causes DIPM enable commands to be processed with mismatching controller power state and link->lpm_policy value. In ahci, link->lpm_policy is used to ignore certain PHY events if LPM is enabled; however, as DIPM commands are issued with stale link->lpm_policy, they sometimes end up triggering these conditions and get aborted leading to LPM configuration failure. Fix it by updating link->lpm_policy before issuing DIPM enable commands. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Kyle McMartin <kyle@mcmartin.ca> Cc: stable@kernel.org --- drivers/ata/libata-eh.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html