This is a note to let you know that I've just added the patch titled
scsi: sd: Consider max_xfer_blocks if opt_xfer_blocks is unusable
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
scsi-sd-consider-max_xfer_blocks-if-opt_xfer_blocks-is-unusable.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 6780414519f91c2a84da9baa963a940ac916f803 Mon Sep 17 00:00:00 2001
From: Fam Zheng <famz@xxxxxxxxxx>
Date: Tue, 28 Mar 2017 12:41:26 +0800
Subject: scsi: sd: Consider max_xfer_blocks if opt_xfer_blocks is unusable
From: Fam Zheng <famz@xxxxxxxxxx>
commit 6780414519f91c2a84da9baa963a940ac916f803 upstream.
If device reports a small max_xfer_blocks and a zero opt_xfer_blocks, we
end up using BLK_DEF_MAX_SECTORS, which is wrong and r/w of that size
may get error.
[mkp: tweaked to avoid setting rw_max twice and added typecast]
Fixes: ca369d51b3e ("block/sd: Fix device-imposed transfer length limits")
Signed-off-by: Fam Zheng <famz@xxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/scsi/sd.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -2877,7 +2877,8 @@ static int sd_revalidate_disk(struct gen
q->limits.io_opt = logical_to_bytes(sdp, sdkp->opt_xfer_blocks);
rw_max = logical_to_sectors(sdp, sdkp->opt_xfer_blocks);
} else
- rw_max = BLK_DEF_MAX_SECTORS;
+ rw_max = min_not_zero(logical_to_sectors(sdp, dev_max),
+ (sector_t)BLK_DEF_MAX_SECTORS);
/* Combine with controller limits */
q->limits.max_sectors = min(rw_max, queue_max_hw_sectors(q));
Patches currently in stable-queue which might be from famz@xxxxxxxxxx are
queue-4.9/scsi-sd-consider-max_xfer_blocks-if-opt_xfer_blocks-is-unusable.patch