Re: WARNING in __folio_mark_dirty

[Matthew Wilcox]

On Wed, Nov 10, 2021 at 09:20:38AM +0800, Hao Sun wrote:
> Hello,
> 
> When using Healer to fuzz the latest Linux kernel, the following crash
> was triggered.

It's still a bug in nilfs, just like the last time this was reported.

> HEAD commit: 6b75d88fa81b Merge branch 'i2c/for-current'
> git tree: upstream
> console output: https://paste.ubuntu.com/p/C22bhzvZP6/
> kernel config: https://paste.ubuntu.com/p/b62Hp7BfJn/
> C reproducer: https://paste.ubuntu.com/p/2mchRNDJr4/
> Syzlang reproducer: https://paste.ubuntu.com/p/xM3DQ2f5Qz/
> 
> If you fix this issue, please add the following tag to the commit:
> Reported-by: Hao Sun <sunhao.th@xxxxxxxxx>
> 
> NILFS (loop10): segctord starting. Construction interval = 5 seconds,
> CP frequency < 30 seconds
> ------------[ cut here ]------------
> WARNING: CPU: 3 PID: 18327 at include/linux/backing-dev.h:269
> inode_to_wb include/linux/backing-dev.h:269 [inline]
> WARNING: CPU: 3 PID: 18327 at include/linux/backing-dev.h:269
> folio_account_dirtied mm/page-writeback.c:2460 [inline]
> WARNING: CPU: 3 PID: 18327 at include/linux/backing-dev.h:269
> __folio_mark_dirty+0xab2/0xe80 mm/page-writeback.c:2509
> Modules linked in:
> CPU: 3 PID: 18327 Comm: segctord Not tainted 5.15.0+ #6
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> 1.13.0-1ubuntu1.1 04/01/2014
> RIP: 0010:inode_to_wb include/linux/backing-dev.h:269 [inline]
> RIP: 0010:folio_account_dirtied mm/page-writeback.c:2460 [inline]
> RIP: 0010:__folio_mark_dirty+0xab2/0xe80 mm/page-writeback.c:2509
> Code: ff ff ff 48 8d 78 70 e8 8c 69 96 07 31 ff 89 c6 89 44 24 10 e8
> ff 52 d8 ff 8b 44 24 10 85 c0 0f 85 13 fa ff ff e8 8e 51 d8 ff <0f> 0b
> e9 07 fa ff ff e8 82 51 d8 ff e8 9d 6a 96 07 31 ff 41 89 c7
> RSP: 0018:ffffc900076ef7c0 EFLAGS: 00010046
> RAX: 0000000000000000 RBX: ffff88802c478378 RCX: ffff88802fc33980
> RDX: 0000000000000000 RSI: ffff88802fc33980 RDI: 0000000000000002
> RBP: ffffea0000b7ca80 R08: ffffffff819f0012 R09: 0000000000000000
> R10: 0000000000000005 R11: fffff9400016f950 R12: 0000000000000246
> R13: ffff88802c478138 R14: 0000000000000001 R15: 0000000000000001
> FS: 0000000000000000(0000) GS:ffff888135d00000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 000056054d573c18 CR3: 0000000021c4e000 CR4: 0000000000350ee0
> Call Trace:
> <TASK>
> __set_page_dirty include/linux/pagemap.h:784 [inline]
> mark_buffer_dirty+0x501/0x6a0 fs/buffer.c:1108
> nilfs_btree_propagate_p fs/nilfs2/btree.c:1889 [inline]
> nilfs_btree_propagate+0x4ba/0xce0 fs/nilfs2/btree.c:2085
> nilfs_bmap_propagate+0x73/0x170 fs/nilfs2/bmap.c:337
> nilfs_collect_dat_data+0x45/0xd0 fs/nilfs2/segment.c:625
> nilfs_segctor_apply_buffers+0x149/0x480 fs/nilfs2/segment.c:1009
> nilfs_segctor_scan_file+0x3d9/0x570 fs/nilfs2/segment.c:1058
> nilfs_segctor_collect_blocks+0xa33/0x2fb0 fs/nilfs2/segment.c:1224
> nilfs_segctor_collect fs/nilfs2/segment.c:1494 [inline]
> nilfs_segctor_do_construct+0x1228/0x5ef0 fs/nilfs2/segment.c:2036
> nilfs_segctor_construct+0x79f/0xb10 fs/nilfs2/segment.c:2372
> nilfs_segctor_thread_construct fs/nilfs2/segment.c:2480 [inline]
> nilfs_segctor_thread+0x3be/0xe40 fs/nilfs2/segment.c:2563
> kthread+0x405/0x4f0 kernel/kthread.c:327
> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
> </TASK>
>