It was reported that some devices report an OPTIMAL TRANSFER LENGTH of 0xFFFF blocks. That looks bogus, especially for a device with a 4096-byte physical block size.

Ignore OPTIMAL TRANSFER LENGTH if it is not a multiple of the device's reported physical block size.

Cc: stable@vger.kernel.org Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199759 Reported-by: Christoph Anton Mitterer calestyo@scientia.net Signed-off-by: Martin K. Petersen martin.petersen@oracle.com

---

Before:

NAME ALIGNMENT MIN-IO OPT-IO PHY-SEC LOG-SEC ROTA SCHED RQ-SIZE RA WSAME sda 0 4096 33553920 4096 512 0 mq-deadline 256 128 32M

After:

NAME ALIGNMENT MIN-IO OPT-IO PHY-SEC LOG-SEC ROTA SCHED RQ-SIZE RA WSAME sda 0 4096 0 4096 512 0 mq-deadline 256 4096 32M --- drivers/scsi/sd.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 9421d9877730..2d19eed3dfbc 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -3067,7 +3067,7 @@ static int sd_revalidate_disk(struct gendisk *disk) struct request_queue *q = sdkp->disk->queue; sector_t old_capacity = sdkp->capacity; unsigned char *buffer; - unsigned int dev_max, rw_max; + unsigned int dev_max, rw_max, opt_xfer_bytes;

SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_revalidate_disk\n")); @@ -3126,13 +3126,16 @@ static int sd_revalidate_disk(struct gendisk *disk)

/* * Determine the device's preferred I/O size for reads and writes - * unless the reported value is unreasonably small, large, or - * garbage. + * unless the reported value is unreasonably small, large, not a + * multiple of the physical block size, or simply garbage. */ + opt_xfer_bytes = logical_to_bytes(sdp, sdkp->opt_xfer_blocks); + if (sdkp->opt_xfer_blocks && sdkp->opt_xfer_blocks <= dev_max && sdkp->opt_xfer_blocks <= SD_DEF_XFER_BLOCKS && - logical_to_bytes(sdp, sdkp->opt_xfer_blocks) >= PAGE_SIZE) { + opt_xfer_bytes >= PAGE_SIZE && + (opt_xfer_bytes & (sdkp->physical_block_size - 1)) != 0) { q->limits.io_opt = logical_to_bytes(sdp, sdkp->opt_xfer_blocks); rw_max = logical_to_sectors(sdp, sdkp->opt_xfer_blocks); } else