If the drive has indicated to us that it doesn't have any media in
it, don't bother after the third poll indicating "media_not_present".
Previously we gave up immediately after the first indication, however
two retries were still available for orther cases.
This change solved a problem of mounting the root filesystem via the
"root=PARTUUID=..." kernel directive, while booting the system from
the USB flash drive (18a5:0302 Verbatim).
Using the "root=/dev/sd.." directive, disk partitions are discovered
and the root filesystem mounts without errors. But, in the error case
(root=PARTUUID=...), partitions never get discovered and consequetly
the root filesystem never mounts.
---
drivers/scsi/sd.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 39754cc90043..7f391164f646 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -2101,10 +2101,16 @@ sd_spinup_disk(struct scsi_disk *sdkp)
/*
* If the drive has indicated to us that it
* doesn't have any media in it, don't bother
- * with any more polling.
+ * after the third poll.
*/
- if (media_not_present(sdkp, &sshdr))
- return;
+ if (media_not_present(sdkp, &sshdr)) {
+ retries++;
+ if (retries < 3) {
+ sdkp->media_present = 1;
+ continue;
+ } else
+ return;
+ }
if (the_result)
sense_valid = scsi_sense_valid(&sshdr);
--
2.17.1
