On Sat, Mar 26, 2016 at 05:46:16PM +0100, Sebastian Roesner wrote: > Hello Ming, Eric, > > Am 26.03.2016 um 16:40 schrieb Ming Lei: > > From the trace, looks the bio returned from bio_clone_mddev() is NULL, > >and maybe the source bio is buggy, something like the attached patch > >might be helpful, could you apply the attached debug patch, reproduce > >and post the log? > > I was able to reproduce it on a non-productive system, but only after > copying the bcache superblocks/partition starts from the original system, > with new created ones it worked fine. > > Full trace and check_bio output can be found here: > > http://pastebin.com/ngvGGHBZ 320 bvecs exceeds what bio-clone_set can handle. Could you please try below patch? commit 92761dad7ff6e1bf25de247e0064dd398e797599 Author: Shaohua Li <shli@xxxxxx> Date: Mon Mar 28 10:54:35 2016 -0700 block: don't make BLK_DEF_MAX_SECTORS too big bio_alloc_bioset() allocates bvecs from bvec_slabs which can only allocate maximum 256 bvec (eg, 1M for 4k pages). We can't bump BLK_DEF_MAX_SECTORS to exceed this value otherwise bio_alloc_bioset will fail. This fixes commit 30e2bc08b2bb7c069. We probably should make the bvec_slabs hold bigger bvecs if bigger bio size is required. Signed-off-by: Shaohua Li <shli@xxxxxx> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 7e5d7e0..da64325 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1153,7 +1153,11 @@ extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); enum blk_default_limits { BLK_MAX_SEGMENTS = 128, BLK_SAFE_MAX_SECTORS = 255, - BLK_DEF_MAX_SECTORS = 2560, + /* + * if you change this, please also change bvec_alloc and BIO_MAX_PAGES. + * Otherwise bio_alloc_bioset will break. + */ + BLK_DEF_MAX_SECTORS = BIO_MAX_SECTORS, BLK_MAX_SEGMENT_SIZE = 65536, BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, }; -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
