Re: [syzbot] INFO: task hung in __filemap_get_folio

From: syzbot
Date: Sat Sep 10 2022 - 03:06:36 EST


syzbot has found a reproducer for the following issue on:

HEAD commit: e47eb90a0a9a Add linux-next specific files for 20220901
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=12e05825080000
kernel config: https://syzkaller.appspot.com/x/.config?x=7933882276523081
dashboard link: https://syzkaller.appspot.com/bug?extid=0e9dc403e57033a74b1d
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=116a3953080000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0e9dc403e57033a74b1d@xxxxxxxxxxxxxxxxxxxxxxxxx

INFO: task syz-executor.3:5563 blocked for more than 143 seconds.
Not tainted 6.0.0-rc3-next-20220901-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3 state:D
stack:26944 pid:5563 ppid:3713 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5197 [inline]
__schedule+0xae5/0x52c0 kernel/sched/core.c:6509
schedule+0xda/0x1b0 kernel/sched/core.c:6585
io_schedule+0xba/0x130 kernel/sched/core.c:8729
folio_wait_bit_common+0x49f/0xa20 mm/filemap.c:1295
__folio_lock mm/filemap.c:1658 [inline]
folio_lock include/linux/pagemap.h:939 [inline]
folio_lock include/linux/pagemap.h:935 [inline]
__filemap_get_folio+0xc6d/0xed0 mm/filemap.c:1930
truncate_inode_pages_range+0x37c/0x1510 mm/truncate.c:378
ntfs_evict_inode+0x16/0xa0 fs/ntfs3/inode.c:1741
evict+0x2ed/0x6b0 fs/inode.c:666
iput_final fs/inode.c:1749 [inline]
iput.part.0+0x55d/0x810 fs/inode.c:1775
iput+0x58/0x70 fs/inode.c:1765
ntfs_fill_super+0x2309/0x37f0 fs/ntfs3/super.c:1278
get_tree_bdev+0x440/0x760 fs/super.c:1323
vfs_get_tree+0x89/0x2f0 fs/super.c:1530
do_new_mount fs/namespace.c:3040 [inline]
path_mount+0x1326/0x1e20 fs/namespace.c:3370
do_mount fs/namespace.c:3383 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount fs/namespace.c:3568 [inline]
__x64_sys_mount+0x27f/0x300 fs/namespace.c:3568
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f62c488a8fa
RSP: 002b:00007fff05d56558 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007f62c488a8fa
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007fff05d565b0
RBP: 00007fff05d565f0 R08: 00007fff05d565f0 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000000
R13: 0000000020000100 R14: 00007fff05d565b0 R15: 000000002007aa80
</TASK>
NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.0.0-rc3-next-20220901-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
nmi_cpu_backtrace.cold+0x46/0x14f lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x206/0x250 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:227 [inline]
watchdog+0xcf7/0xfd0 kernel/hung_task.c:384
kthread+0x2e4/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 2973 Comm: udevd Not tainted 6.0.0-rc3-next-20220901-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
RIP: 0033:0x7f2aff58ebf8
Code: f8 c5 fa 7e 0f c5 fa 7e 16 c5 e9 74 d1 c5 f9 d7 c2 2d ff ff 00 00 0f 85 06 ff ff ff c3 0f 1f 44 00 00 c5 fa 6f 16 c5 e9 74 17 <c5> f9 d7 c2 2d ff ff 00 00 0f 85 e9 fe ff ff 48 8d 7c 17 f0 48 8d
RSP: 002b:00007fff5dda79e8 EFLAGS: 00000206
RAX: 0000000000000007 RBX: 000055e68d0e4a70 RCX: 0000000000000000
RDX: 000000000000001c RSI: 000055e68d0e44b4 RDI: 000055e68cdc2e44
RBP: 000055e68cdc3380 R08: 000000000000001c R09: 000000000000001c
R10: 0000000000000002 R11: 0000000000000020 R12: 0000000000003a94
R13: 0000000000000703 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f2aff8ae840 GS: 0000000000000000