From: Keith Busch kbusch@kernel.org
commit e4b469c66f3cbb81c2e94d31123d7bcdf3c1dabd upstream.
A previous commit aligning splits to physical block sizes inadvertently modified one return case such that that it now returns 0 length splits when the number of sectors doesn't exceed the physical offset. This later hits a BUG in bio_split(). Restore the previous working behavior.
Fixes: 9cc5169cd478b ("block: Improve physical block alignment of split bios") Reported-by: Eric Deal eric.deal@wdc.com Signed-off-by: Keith Busch kbusch@kernel.org Cc: Bart Van Assche bvanassche@acm.org Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- block/blk-merge.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -154,7 +154,7 @@ static inline unsigned get_max_io_size(s if (max_sectors > start_offset) return max_sectors - start_offset;
- return sectors & (lbs - 1); + return sectors & ~(lbs - 1); }
static inline unsigned get_max_segment_size(const struct request_queue *q,