fstest reports a f2fs bug:
generic/363 42s ... [failed, exit status 1]- output mismatch (see /share/git/fstests/results//generic/363.out.bad)
--- tests/generic/363.out 2025-01-12 21:57:40.271440542 +0800
+++ /share/git/fstests/results//generic/363.out.bad 2025-05-19 19:55:58.000000000 +0800
@@ -1,2 +1,78 @@
QA output created by 363
fsx -q -S 0 -e 1 -N 100000
+READ BAD DATA: offset = 0xd6fb, size = 0xf044, fname = /mnt/f2fs/junk
+OFFSET GOOD BAD RANGE
+0x1540d 0x0000 0x2a25 0x0
+operation# (mod 256) for the bad data may be 37
+0x1540e 0x0000 0x2527 0x1
...
(Run 'diff -u /share/git/fstests/tests/generic/363.out /share/git/fstests/results//generic/363.out.bad' to see the entire diff)
Ran: generic/363
Failures: generic/363
Failed 1 of 1 tests
The root cause is user can update post-eof page via mmap [1], however, f2fs
missed to zero post-eof page in below operations, so, once it expands i_size,
then it will include dummy data locates previous post-eof page, so during
below operations, we need to zero post-eof page.
Operations which can include dummy data after previous i_size after expanding
i_size:
- write
- mapwrite [1]
- truncate
- fallocate
* preallocate
* zero_range
* insert_range
* collapse_range
- clone_range (doesn’t support in f2fs)
- copy_range (doesn’t support in f2fs)
[1] https://man7.org/linux/man-pages/man2/mmap.2.html 'BUG section'
Cc: stable@kernel.org
Signed-off-by: Chao Yu <chao@kernel.org>
Reviewed-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This conversion moved the folio_unlock() to inside __write_node_folio(), but missed one caller so we had a double-unlock on this path. Cc: Christoph Hellwig <hch@lst.de> Cc: Chao Yu <chao@kernel.org> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Reported-by: syzbot+c0dc46208750f063d0e0@syzkaller.appspotmail.com Fixes: 80f31d2a7e5f (f2fs: return bool from __write_node_folio) Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Pull f2fs updates from Jaegeuk Kim:
"In this round, Matthew converted most of page operations to using
folio. Beyond the work, we've applied some performance tunings such as
GC and linear lookup, in addition to enhancing fault injection and
sanity checks.
Enhancements:
- large number of folio conversions
- add a control to turn on/off the linear lookup for performance
- tune GC logics for zoned block device
- improve fault injection and sanity checks
Bug fixes:
- handle error cases of memory donation
- fix to correct check conditions in f2fs_cross_rename
- fix to skip f2fs_balance_fs() if checkpoint is disabled
- don't over-report free space or inodes in statvfs
- prevent the current section from being selected as a victim during GC
- fix to calculate first_zoned_segno correctly
- fix to avoid inconsistence between SIT and SSA for zoned block device
As usual, there are several debugging patches and clean-ups as well"
* tag 'f2fs-for-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (195 commits)
f2fs: fix to correct check conditions in f2fs_cross_rename
f2fs: use d_inode(dentry) cleanup dentry->d_inode
f2fs: fix to skip f2fs_balance_fs() if checkpoint is disabled
f2fs: clean up to check bi_status w/ BLK_STS_OK
f2fs: introduce is_{meta,node}_folio
f2fs: add ckpt_valid_blocks to the section entry
f2fs: add a method for calculating the remaining blocks in the current segment in LFS mode.
f2fs: introduce FAULT_VMALLOC
f2fs: use vmalloc instead of kvmalloc in .init_{,de}compress_ctx
f2fs: add f2fs_bug_on() in f2fs_quota_read()
f2fs: add f2fs_bug_on() to detect potential bug
f2fs: remove unused sbi argument from checksum functions
f2fs: fix 32-bits hexademical number in fault injection doc
f2fs: don't over-report free space or inodes in statvfs
f2fs: return bool from __write_node_folio
f2fs: simplify return value handling in f2fs_fsync_node_pages
f2fs: always unlock the page in f2fs_write_single_data_page
f2fs: remove wbc->for_reclaim handling
f2fs: return bool from __f2fs_write_meta_folio
f2fs: fix to return correct error number in f2fs_sync_node_pages()
...
Should be "old_dir" here.
Fixes: 5c57132eaf52 ("f2fs: support project quota")
Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
no logic changes. Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Syzbot reports a f2fs bug as below:
INFO: task syz-executor328:5856 blocked for more than 144 seconds.
Not tainted 6.15.0-rc6-syzkaller-00208-g3c21441eeffc #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor328 state:D stack:24392 pid:5856 tgid:5832 ppid:5826 task_flags:0x400040 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
io_schedule+0x81/0xe0 kernel/sched/core.c:7742
f2fs_balance_fs+0x4b4/0x780 fs/f2fs/segment.c:444
f2fs_map_blocks+0x3af1/0x43b0 fs/f2fs/data.c:1791
f2fs_expand_inode_data+0x653/0xaf0 fs/f2fs/file.c:1872
f2fs_fallocate+0x4f5/0x990 fs/f2fs/file.c:1975
vfs_fallocate+0x6a0/0x830 fs/open.c:338
ioctl_preallocate fs/ioctl.c:290 [inline]
file_ioctl fs/ioctl.c:-1 [inline]
do_vfs_ioctl+0x1b8f/0x1eb0 fs/ioctl.c:885
__do_sys_ioctl fs/ioctl.c:904 [inline]
__se_sys_ioctl+0x82/0x170 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The root cause is after commit 84b5bb8bf0f6 ("f2fs: modify
f2fs_is_checkpoint_ready logic to allow more data to be written with the
CP disable"), we will get chance to allow f2fs_is_checkpoint_ready() to
return true once below conditions are all true:
1. checkpoint is disabled
2. there are not enough free segments
3. there are enough free blocks
Then it will cause f2fs_balance_fs() to trigger foreground GC.
void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need)
...
if (!f2fs_is_checkpoint_ready(sbi))
return;
And the testcase mounts f2fs image w/ gc_merge,checkpoint=disable, so deadloop
will happen through below race condition:
- f2fs_do_shutdown - vfs_fallocate - gc_thread_func
- file_start_write
- __sb_start_write(SB_FREEZE_WRITE)
- f2fs_fallocate
- f2fs_expand_inode_data
- f2fs_map_blocks
- f2fs_balance_fs
- prepare_to_wait
- wake_up(gc_wait_queue_head)
- io_schedule
- bdev_freeze
- freeze_super
- sb->s_writers.frozen = SB_FREEZE_WRITE;
- sb_wait_write(sb, SB_FREEZE_WRITE);
- if (sbi->sb->s_writers.frozen >= SB_FREEZE_WRITE) continue;
: cause deadloop
This patch fix to add check condition in f2fs_balance_fs(), so that if
checkpoint is disabled, we will just skip trigger foreground GC to
avoid such deadloop issue.
Meanwhile let's remove f2fs_is_checkpoint_ready() check condition in
f2fs_balance_fs(), since it's redundant, due to the main logic in the
function is to check:
a) whether checkpoint is disabled
b) there is enough free segments
f2fs_balance_fs() still has all logics after f2fs_is_checkpoint_ready()'s
removal.
Reported-by: syzbot+aa5bb5f6860e08a60450@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-f2fs-devel/682d743a.a00a0220.29bc26.0289.GAE@google.com
Fixes: 84b5bb8bf0f6 ("f2fs: modify f2fs_is_checkpoint_ready logic to allow more data to be written with the CP disable")
Cc: Qi Han <hanqi@vivo.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Reviewed-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Check bi_status w/ BLK_STS_OK instead of 0 for cleanup. Signed-off-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Just cleanup, no changes. Signed-off-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
when performing buffered writes in a large section, overhead is incurred due to the iteration through ckpt_valid_blocks within the section. when SEGS_PER_SEC is 128, this overhead accounts for 20% within the f2fs_write_single_data_page routine. as the size of the section increases, the overhead also grows. to handle this problem ckpt_valid_blocks is added within the section entries. Test insmod null_blk.ko nr_devices=1 completion_nsec=1 submit_queues=8 hw_queue_depth=64 max_sectors=512 bs=4096 memory_backed=1 make_f2fs /dev/block/nullb0 make_f2fs -s 128 /dev/block/nullb0 fio --bs=512k --size=1536M --rw=write --name=1 --filename=/mnt/test_dir/seq_write --ioengine=io_uring --iodepth=64 --end_fsync=1 before SEGS_PER_SEC 1 2556MiB/s SEGS_PER_SEC 128 2145MiB/s after SEGS_PER_SEC 1 2556MiB/s SEGS_PER_SEC 128 2556MiB/s Signed-off-by: yohan.joung <yohan.joung@sk.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In LFS mode, the previous segment cannot use invalid blocks, so the remaining blocks from the next_blkoff of the current segment to the end of the section are calculated. Signed-off-by: yohan.joung <yohan.joung@sk.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>