diff options
| author | Guoqing Jiang <jiangguoqing@kylinos.cn> | 2021-08-24 04:16:54 +0300 |
|---|---|---|
| committer | Song Liu <songliubraving@fb.com> | 2021-08-28 01:12:14 +0300 |
| commit | 6607cd319b6b91bff94e90f798a61c031650b514 (patch) | |
| tree | 2b1baab8e9462a35f47d16ca98cc937584e52f93 /drivers/md | |
| parent | 46d4703b1db4c86ab5acb2331b10df999f005e8e (diff) | |
| download | linux-6607cd319b6b91bff94e90f798a61c031650b514.tar.xz | |
raid1: ensure write behind bio has less than BIO_MAX_VECS sectors
We can't split write behind bio with more than BIO_MAX_VECS sectors,
otherwise the below call trace was triggered because we could allocate
oversized write behind bio later.
[ 8.097936] bvec_alloc+0x90/0xc0
[ 8.098934] bio_alloc_bioset+0x1b3/0x260
[ 8.099959] raid1_make_request+0x9ce/0xc50 [raid1]
[ 8.100988] ? __bio_clone_fast+0xa8/0xe0
[ 8.102008] md_handle_request+0x158/0x1d0 [md_mod]
[ 8.103050] md_submit_bio+0xcd/0x110 [md_mod]
[ 8.104084] submit_bio_noacct+0x139/0x530
[ 8.105127] submit_bio+0x78/0x1d0
[ 8.106163] ext4_io_submit+0x48/0x60 [ext4]
[ 8.107242] ext4_writepages+0x652/0x1170 [ext4]
[ 8.108300] ? do_writepages+0x41/0x100
[ 8.109338] ? __ext4_mark_inode_dirty+0x240/0x240 [ext4]
[ 8.110406] do_writepages+0x41/0x100
[ 8.111450] __filemap_fdatawrite_range+0xc5/0x100
[ 8.112513] file_write_and_wait_range+0x61/0xb0
[ 8.113564] ext4_sync_file+0x73/0x370 [ext4]
[ 8.114607] __x64_sys_fsync+0x33/0x60
[ 8.115635] do_syscall_64+0x33/0x40
[ 8.116670] entry_SYSCALL_64_after_hwframe+0x44/0xae
Thanks for the comment from Christoph.
[1]. https://bugs.archlinux.org/task/70992
Cc: stable@vger.kernel.org # v5.12+
Reported-by: Jens Stutte <jens@chianterastutte.eu>
Tested-by: Jens Stutte <jens@chianterastutte.eu>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <songliubraving@fb.com>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/raid1.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 51f2547c2007..21b348408478 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1331,6 +1331,7 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, struct raid1_plug_cb *plug = NULL; int first_clone; int max_sectors; + bool write_behind = false; if (mddev_is_clustered(mddev) && md_cluster_ops->area_resyncing(mddev, WRITE, @@ -1383,6 +1384,15 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, max_sectors = r1_bio->sectors; for (i = 0; i < disks; i++) { struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); + + /* + * The write-behind io is only attempted on drives marked as + * write-mostly, which means we could allocate write behind + * bio later. + */ + if (rdev && test_bit(WriteMostly, &rdev->flags)) + write_behind = true; + if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { atomic_inc(&rdev->nr_pending); blocked_rdev = rdev; @@ -1456,6 +1466,15 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, goto retry_write; } + /* + * When using a bitmap, we may call alloc_behind_master_bio below. + * alloc_behind_master_bio allocates a copy of the data payload a page + * at a time and thus needs a new bio that can fit the whole payload + * this bio in page sized chunks. + */ + if (write_behind && bitmap) + max_sectors = min_t(int, max_sectors, + BIO_MAX_VECS * (PAGE_SIZE >> 9)); if (max_sectors < bio_sectors(bio)) { struct bio *split = bio_split(bio, max_sectors, GFP_NOIO, &conf->bio_split); |