Message-ID: <6879a305.a70a0220.693ce.0058.GAE@google.com>
Date: Thu, 17 Jul 2025 18:27:33 -0700
From: syzbot <syzbot+c2294ae43bae606e3c7d@...kaller.appspotmail.com>
To: anna-maria@...utronix.de, frederic@...nel.org, kent.overstreet@...ux.dev, 
	linux-bcachefs@...r.kernel.org, linux-kernel@...r.kernel.org, 
	syzkaller-bugs@...glegroups.com, tglx@...utronix.de
Subject: [syzbot] [bcachefs?] INFO: task hung in bch2_run_recovery_passes

Hello,

syzbot found the following issue on:

HEAD commit:    aaef6f251176 Merge branches 'for-next/core' and 'for-next/..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=162817d4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=167a38bcf05390d5
dashboard link: https://syzkaller.appspot.com/bug?extid=c2294ae43bae606e3c7d
compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
userspace arch: arm64
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=112817d4580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/dfd0a4db9e57/disk-aaef6f25.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/602c89e1c208/vmlinux-aaef6f25.xz
kernel image: https://storage.googleapis.com/syzbot-assets/82e8ab4e1b11/Image-aaef6f25.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/780ac1e01de6/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c2294ae43bae606e3c7d@...kaller.appspotmail.com

INFO: task syz.1.22:6793 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc6-syzkaller-gaaef6f251176 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.22        state:D stack:0     pid:6793  tgid:6793  ppid:6662   task_flags:0x400140 flags:0x00000019
Call trace:
 __switch_to+0x414/0x834 arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x1414/0x2a28 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6879
 schedule_timeout+0xac/0x270 kernel/time/sleep_timeout.c:75
 ___down_common+0x23c/0x374 kernel/locking/semaphore.c:268
 __down_common+0xc0/0x3a4 kernel/locking/semaphore.c:293
 __down+0x18/0x24 kernel/locking/semaphore.c:303
 down+0x94/0xe8 kernel/locking/semaphore.c:100
 bch2_run_recovery_passes+0x164/0x1f4 fs/bcachefs/recovery_passes.c:609
 bch2_fs_recovery+0x1df4/0x2fb4 fs/bcachefs/recovery.c:1050
 bch2_fs_start+0x940/0xbec fs/bcachefs/super.c:1213
 bch2_fs_get_tree+0x880/0x107c fs/bcachefs/fs.c:2488
 vfs_get_tree+0x90/0x28c fs/super.c:1804
 do_new_mount+0x228/0x814 fs/namespace.c:3902
 path_mount+0x5b4/0xde0 fs/namespace.c:4226
 do_mount fs/namespace.c:4239 [inline]
 __do_sys_mount fs/namespace.c:4450 [inline]
 __se_sys_mount fs/namespace.c:4427 [inline]
 __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4427
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Showing all locks held in the system:
2 locks held by kworker/u8:0/12:
1 lock held by khungtaskd/32:
 #0: ffff80008f869980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
5 locks held by kworker/u8:2/41:
 #0: ffff0000dafdd148 ((wq_completion)btree_update#272){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3212
 #1: ffff8000990f7bc0 ((work_completion)(&c->btree_interior_update_work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3212
 #2: ffff00010b404398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire+0x18/0x54 include/linux/srcu.h:160
 #3: ffff0001078f01b0 (bcachefs_btree){+.+.}-{0:0}, at: trans_set_locked+0x68/0x200 fs/bcachefs/btree_locking.h:205
 #4: ffff00010b400920 (&c->sb_lock){+.+.}-{4:4}, at: btree_update_new_nodes_mark_sb fs/bcachefs/btree_update_interior.c:609 [inline]
 #4: ffff00010b400920 (&c->sb_lock){+.+.}-{4:4}, at: btree_update_nodes_written fs/bcachefs/btree_update_interior.c:683 [inline]
 #4: ffff00010b400920 (&c->sb_lock){+.+.}-{4:4}, at: btree_interior_update_work+0x2e8/0x1d28 fs/bcachefs/btree_update_interior.c:867
2 locks held by pr/ttyAMA0/43:
2 locks held by kworker/u8:6/352:
 #0: ffff0000c0031148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3212
 #1: ffff80009bed7bc0 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3212
2 locks held by kworker/u8:8/4125:
5 locks held by kworker/u8:9/4137:
 #0: ffff0000fbc4b948 ((wq_completion)btree_update#271){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3212
 #1: ffff8000a0197bc0 ((work_completion)(&c->btree_interior_update_work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3212
 #2: ffff00010d304398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire+0x18/0x54 include/linux/srcu.h:160
 #3: ffff000104da81b0 (bcachefs_btree){+.+.}-{0:0}, at: trans_set_locked+0x68/0x200 fs/bcachefs/btree_locking.h:205
 #4: ffff00010d300920 (&c->sb_lock){+.+.}-{4:4}, at: btree_update_new_nodes_mark_sb fs/bcachefs/btree_update_interior.c:609 [inline]
 #4: ffff00010d300920 (&c->sb_lock){+.+.}-{4:4}, at: btree_update_nodes_written fs/bcachefs/btree_update_interior.c:683 [inline]
 #4: ffff00010d300920 (&c->sb_lock){+.+.}-{4:4}, at: btree_interior_update_work+0x2e8/0x1d28 fs/bcachefs/btree_update_interior.c:867
2 locks held by getty/6289:
 #0: ffff0000c19cc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009ba3e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfa4 drivers/tty/n_tty.c:2222
3 locks held by kworker/1:3/6710:
2 locks held by syz.0.299/9979:
3 locks held by syz.5.300/9983:

=============================================



---
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