From fd106ada4dee4b8adefec791ee9b9681b7b77501 Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Mon, 19 Oct 2026 09:00:32 +0000 Subject: [PATCH] f2fs: zone: fix to don't fail to grab GC target block on zoned device With out-of-memory fault injection (inject_type=0x0080800f) on a zoned device, f2fs stopped checkpoint during GC: F2FS-fs (dm-0): inject kmalloc in f2fs_kmalloc of move_data_block+0xc0b/0x12b0 Workqueue: dm-1_zwplugs blk_zone_wplug_bio_work Call Trace: dump_stack_lvl+0x4d/0x70 f2fs_stop_checkpoint+0x1df/0x5d0 f2fs_write_end_bio+0xdbb/0x1320 blk_zone_wplug_bio_work+0x2aa/0x7d0 process_one_work+0x5c6/0xde0 worker_thread+0x403/0xb70 kthread+0x235/0x2e0 ret_from_fork+0x2f/0x70 ret_from_fork_asm+0x1a/0x30 F2FS-fs (dm-0): Stopped filesystem due to reason: 3 In move_data_block(), the target block is grabbed from the meta cache after f2fs_allocate_data_block() has allocated newaddr. If grabbing it fails w/ -ENOMEM, recover_block calls f2fs_do_replace_block() to restore the old block address and curseg's next_blkoff, which already points past newaddr, so newaddr is never written. That leaves a hole in a sequential zone: the next write to the zone is not at the write pointer, the zone write plug fails it, and f2fs_write_end_bio() stops checkpoint w/ STOP_CP_REASON_WRITE_FAIL. move_data_block() allocates newaddr before grabbing its meta page and goes to recover_block if the grab fails since commit 4356e48e6437 ("f2fs crypto: fix incorrect positioning for GCing encrypted data page"), the meta cache only replaced the meta page w/ a meta cache entry. That is harmless on a regular device, but it leaves the hole since f2fs supports host-managed SMR (now zoned block) devices, which only accept writes at the write pointer of a sequential zone. If newaddr is in a sequential zone, grab the target block w/ F2FS_CACHE_NOFAIL, so nothing can fail between allocating newaddr and writing it. In a conventional zone or on a regular device, skipping newaddr is harmless, so keep the error handling for them. Cc: stable@kernel.org Fixes: 52763a4b7a21 ("f2fs: detect host-managed SMR by feature flag") Fixes: d1b959c87702 ("f2fs: Check zoned block feature for host-managed zoned block devices") Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/gc.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index 18aa6a12e805..5b948c92f981 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -1453,8 +1453,16 @@ static int move_data_block(struct inode *inode, block_t bidx, goto up_out; } + /* + * If newaddr is in a sequential zone, it must be written once it is + * allocated, otherwise it leaves a hole in the zone, and the following + * write to the zone will fail as an unaligned write, so don't fail + * here. + */ tentry = f2fs_grab_cache(META_CACHE(fio.sbi), newaddr, - F2FS_CACHE_LOCK_CREATE); + F2FS_CACHE_LOCK_CREATE | + (f2fs_is_sequential_zone_area(fio.sbi, newaddr) ? + F2FS_CACHE_NOFAIL : 0)); if (IS_ERR(tentry)) { err = PTR_ERR(tentry); f2fs_put_cache(sentry, true);