After non-classifying reset, ehc->classes[] could contain ATA_DEV_UNKNOWN which used to be normalized to ATA_DEV_NONE for consistency. However, this causes unfortunate side effect for drivers which have non-classifying hardresets (e.g. sata_nv) by making hardreset report ATA_DEV_NONE for non-classifying resets and thus makes EH believe that the port is unoccupied and recovery can be skipped. The end result is that after a device is swapped with another one, the new device isn't attached after the old one is detached. This patch makes ata_eh_reset() not normalize UNKNOWN to NONE after non-classifying resets. This fixes the above problem. As UNKNOWN and NONE are handled differently by only EH hotplug logic, this doesn't cause other behavior changes. Signed-off-by: Tejun Heo <htejun@xxxxxxxxx> Cc: Robert Hancock <hancockr@xxxxxxx> --- Robert, missing new device was a bug in core EH logic not sata_nv. BTW, I did quite a few hotplug tests with adma=0 and it works just fine. No lock up. drivers/ata/libata-eh.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index f0124a8..e7757dd 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -2157,13 +2157,11 @@ int ata_eh_reset(struct ata_link *link, int classify, if (ata_link_offline(link)) continue; - /* apply class override and convert UNKNOWN to NONE */ + /* apply class override */ if (lflags & ATA_LFLAG_ASSUME_ATA) classes[dev->devno] = ATA_DEV_ATA; else if (lflags & ATA_LFLAG_ASSUME_SEMB) classes[dev->devno] = ATA_DEV_SEMB_UNSUP; /* not yet */ - else if (classes[dev->devno] == ATA_DEV_UNKNOWN) - classes[dev->devno] = ATA_DEV_NONE; } /* record current link speed */ - 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
