Re: [syzbot] [jfs?] INFO: task hung in txBegin

From: syzbot
Date: Fri Jul 19 2024 - 23:00:11 EST


Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
BUG: sleeping function called from invalid context in wb_writeback

sb: ffff88802058c000, wb_writeback
BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1578
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2837, name: kworker/u8:7
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
3 locks held by kworker/u8:7/2837:
#0: ffff8880186ea948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
#0: ffff8880186ea948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
#1: ffffc90009a67d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
#1: ffffc90009a67d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
#2: ffff888020b920d8 (&wb->list_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#2: ffff888020b920d8 (&wb->list_lock){+.+.}-{2:2}, at: wb_writeback+0x29e/0xdb0 fs/fs-writeback.c:2106
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 1 PID: 2837 Comm: kworker/u8:7 Not tainted 6.10.0-rc4-syzkaller-00148-g50736169ecc8-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
__might_resched+0x5d4/0x780 kernel/sched/core.c:10196
down_write+0x19/0x50 kernel/locking/rwsem.c:1578
wb_writeback+0x836/0xdb0 fs/fs-writeback.c:2128
wb_do_writeback fs/fs-writeback.c:2278 [inline]
wb_workfn+0x410/0x1090 fs/fs-writeback.c:2318
process_one_work kernel/workqueue.c:3231 [inline]
process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
worker_thread+0x86d/0xd70 kernel/workqueue.c:3393
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>

=============================
[ BUG: Invalid wait context ]
6.10.0-rc4-syzkaller-00148-g50736169ecc8-dirty #0 Tainted: G W
-----------------------------
kworker/u8:7/2837 is trying to lock:
ffff88802058c0e0 (&type->s_umount_key#52){+.+.}-{3:3}, at: wb_writeback+0x836/0xdb0 fs/fs-writeback.c:2128
other info that might help us debug this:
context-{4:4}
3 locks held by kworker/u8:7/2837:
#0: ffff8880186ea948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
#0: ffff8880186ea948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
#1: ffffc90009a67d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
#1: ffffc90009a67d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
#2: ffff888020b920d8 (&wb->list_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#2: ffff888020b920d8 (&wb->list_lock){+.+.}-{2:2}, at: wb_writeback+0x29e/0xdb0 fs/fs-writeback.c:2106
stack backtrace:
CPU: 1 PID: 2837 Comm: kworker/u8:7 Tainted: G W 6.10.0-rc4-syzkaller-00148-g50736169ecc8-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
print_lock_invalid_wait_context kernel/locking/lockdep.c:4751 [inline]
check_wait_context kernel/locking/lockdep.c:4821 [inline]
__lock_acquire+0x1507/0x1fd0 kernel/locking/lockdep.c:5087
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
down_write+0x3a/0x50 kernel/locking/rwsem.c:1579
wb_writeback+0x836/0xdb0 fs/fs-writeback.c:2128
wb_do_writeback fs/fs-writeback.c:2278 [inline]
wb_workfn+0x410/0x1090 fs/fs-writeback.c:2318
process_one_work kernel/workqueue.c:3231 [inline]
process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
worker_thread+0x86d/0xd70 kernel/workqueue.c:3393
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
BUG: scheduling while atomic: kworker/u8:7/2837/0x00000002
INFO: lockdep is turned off.
Modules linked in:
Preemption disabled at:
[<0000000000000000>] 0x0


Tested on:

commit: 50736169 Merge tag 'for-6.10-rc4-tag' of git://git.ker..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=1212f7a5980000
kernel config: https://syzkaller.appspot.com/x/.config?x=12f98862a3c0c799
dashboard link: https://syzkaller.appspot.com/bug?extid=eda89a33c5856f66f823
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch: https://syzkaller.appspot.com/x/patch.diff?x=1442b72d980000