Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  libata: improve phantom device detection

1 files changed, 11 insertions, 2 deletions

diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index 4b4739486327..9033d164c4ec 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -1227,10 +1227,19 @@ fsm_start:
                         /* ATA PIO protocol */
                         if (unlikely((status & ATA_DRQ) == 0)) {
                                 /* handle BSY=0, DRQ=0 as error */
-                                if (likely(status & (ATA_ERR | ATA_DF)))
+                                if (likely(status & (ATA_ERR | ATA_DF))) {
                                         /* device stops HSM for abort/error */
                                         qc->err_mask |= AC_ERR_DEV;
-                                else {
+
+                                        /* If diagnostic failed and this is
+                                         * IDENTIFY, it's likely a phantom
+                                         * device.  Mark hint.
+                                         */
+                                        if (qc->dev->horkage &
+                                            ATA_HORKAGE_DIAGNOSTIC)
+                                                qc->err_mask |=
+                                                        AC_ERR_NODEV_HINT;
+                                } else {
                                         /* HSM violation. Let EH handle this.
                                          * Phantom devices also trigger this
                                          * condition.  Mark hint.