From: Guoqing Jiang <jiangguoqing@xxxxxxxxxx> We can't split 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 [1]. https://bugs.archlinux.org/task/70992 Reported-by: Jens Stutte <jens@xxxxxxxxxxxxxxxxxx> Tested-by: Jens Stutte <jens@xxxxxxxxxxxxxxxxxx> Signed-off-by: Guoqing Jiang <jiangguoqing@xxxxxxxxxx> --- Note: this depends on commit 018eca456c4b4dca56aaf1ec27f309c74d0fe246 in linux-block for-next branch. drivers/md/raid1.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 3c44c4bb40fc..ab21abc056b8 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1454,6 +1454,7 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, goto retry_write; } + max_sectors = min_t(int, max_sectors, BIO_MAX_VECS * PAGE_SECTORS); if (max_sectors < bio_sectors(bio)) { struct bio *split = bio_split(bio, max_sectors, GFP_NOIO, &conf->bio_split); -- 2.25.1
