libata EH intentionally left a port frozen if it failed ata_eh_reset(). The intention was avoiding continuous loop of resets when the controller or attached device is flaky and reporting spurious hotplug events. Once port enters this state, it can be recovered with manual rescan, which seemed reasonable. However, outside of my convoluted test setup, there have been very few reports justifying this choice while there have been more cases where the automatic freezing of the port after hotplug attempt of a faulty device caused confusion and led to unnecessary resets. This patch changes the behavior so that the port is thawed after reset failure. This change doesn't necessarily solve but makes it easier and more intuitive to work around hotplug related problems (ie. re-pluggin or power cycling the device) as reported in the followings. https://bugzilla.kernel.org/show_bug.cgi?id=34712 http://thread.gmane.org/gmane.linux.kernel/1123265/focus=49548 Signed-off-by: Tejun Heo <tj@xxxxxxxxxx> Reported-by: Reartes Guillermo <rtguille@xxxxxxxxx> Reported-by: Bruce Stenning <b.stenning@xxxxxxxxxxxxxxxx> --- drivers/ata/libata-eh.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index dfb6e9d..05797fe 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -2885,8 +2885,17 @@ int ata_eh_reset(struct ata_link *link, int classify, sata_scr_read(link, SCR_STATUS, &sstatus)) rc = -ERESTART; - if (rc == -ERESTART || try >= max_tries) + if (rc == -ERESTART || try >= max_tries) { + /* + * Thaw host port even if reset failed, so that the port + * can be retried on the next phy event. This risks + * repeated EH runs but seems to be a better tradeoff than + * shutting down a port after a botched hotplug attempt. + */ + if (ata_is_host_link(link)) + ata_eh_thaw_port(ap); goto out; + } now = jiffies; if (time_before(now, deadline)) { -- 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
