The following patch fixes an issue observed with 4k sector disks where the max_hw_sectors attribute was getting set too large in sd_revalidate_disk. Since sdkp->max_xfer_blocks is in units of SCSI logical blocks and queue_max_hw_sectors is in units of 512 byte blocks, on a 4k sector disk, every time we went through sd_revalidate_disk, we were taking the current value of queue_max_hw_sectors and increasing it by a factor of 8. Fix this by only shifting sdkp->max_xfer_blocks. Cc: stable<stable@xxxxxxxxxxxxxxx> Signed-off-by: Brian King <brking@xxxxxxxxxxxxxxxxxx> --- drivers/scsi/sd.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff -puN drivers/scsi/sd.c~sd_revalidate_4k drivers/scsi/sd.c --- linux/drivers/scsi/sd.c~sd_revalidate_4k 2015-01-29 14:44:23.316171187 -0600 +++ linux-bjking1/drivers/scsi/sd.c 2015-01-29 14:51:05.846126392 -0600 @@ -2800,9 +2800,11 @@ static int sd_revalidate_disk(struct gen */ sd_set_flush_flag(sdkp); - max_xfer = min_not_zero(queue_max_hw_sectors(sdkp->disk->queue), - sdkp->max_xfer_blocks); + max_xfer = sdkp->max_xfer_blocks; max_xfer <<= ilog2(sdp->sector_size) - 9; + + max_xfer = min_not_zero(queue_max_hw_sectors(sdkp->disk->queue), + max_xfer); blk_queue_max_hw_sectors(sdkp->disk->queue, max_xfer); set_capacity(disk, sdkp->capacity); sd_config_write_same(sdkp); _ -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html