INFO: task syz.2.518:11415 blocked for more than 143 seconds.
Not tainted 6.15.0-rc3-syzkaller-00032-ga79be02bba5c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.518 state:D stack:26952 pid:11415 tgid:11340 ppid:10721 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b33/0x51f0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
rwsem_down_write_slowpath+0xedd/0x1420 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1da/0x220 kernel/locking/rwsem.c:1578
inode_lock include/linux/fs.h:867 [inline]
vfs_link+0x3b2/0x6e0 fs/namei.c:4838
do_linkat+0x55b/0x700 fs/namei.c:4917
__do_sys_link fs/namei.c:4951 [inline]
__se_sys_link fs/namei.c:4949 [inline]
__x64_sys_link+0x82/0x90 fs/namei.c:4949
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fed48d8e969
RSP: 002b:00007fed46bf6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000056
RAX: ffffffffffffffda RBX: 00007fed48fb6080 RCX: 00007fed48d8e969
RDX: 0000000000000000 RSI: 0000200000000300 RDI: 0000200000000200
RBP: 00007fed48e10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fed48fb6080 R15: 00007ffeffc729a8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764
2 locks held by kworker/u8:4/73:
#0: ffff8880b8739998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605
#1: ffff8880b8723b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x41f/0x7a0 kernel/sched/psi.c:987
2 locks held by getty/5583:
#0: ffff8880362da0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/10446:
#0: ffff88802f6220e0 (&type->s_umount_key#70){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline]
#0: ffff88802f6220e0 (&type->s_umount_key#70){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff88802f6220e0 (&type->s_umount_key#70){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505
5 locks held by syz.2.518/11341:
#0: ffff88805ebde420 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556
#1: ffff88805ac20148 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#1: ffff88805ac20148 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: do_truncate+0x20e/0x310 fs/open.c:63
#2: ffff888059680a70 (&c->snapshot_create_lock){.+.+}-{4:4}, at: bch2_truncate+0x1ae/0x340 fs/bcachefs/io_misc.c:295
#3: ffff888059684228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#3: ffff888059684228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#3: ffff888059684228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7ed/0xd40 fs/bcachefs/btree_iter.c:3382
#4: ffff8880596a6590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68a/0x16c0 fs/bcachefs/btree_update_interior.c:1179
3 locks held by syz.2.518/11415:
#0: ffff88805ebde420 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556
#1: ffff88805ac208e0 (&sb->s_type->i_mutex_key#22/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline]
#1: ffff88805ac208e0 (&sb->s_type->i_mutex_key#22/1){+.+.}-{4:4}, at: filename_create+0x262/0x510 fs/namei.c:4132
#2: ffff88805ac20148 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#2: ffff88805ac20148 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: vfs_link+0x3b2/0x6e0 fs/namei.c:4838
2 locks held by bch-copygc/loop/11408:
1 lock held by syz.7.754/13961:
#0: ffff88807f2b5be0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:146 [inline]
#0: ffff88807f2b5be0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x214/0x530 mm/util.c:577
7 locks held by syz.7.754/13962:
1 lock held by syz.9.752/13967:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc3-syzkaller-00032-ga79be02bba5c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:437
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 11408 Comm: bch-copygc/loop Not tainted 6.15.0-rc3-syzkaller-00032-ga79be02bba5c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:bch2_btree_path_verify_level+0x29/0x1920 fs/bcachefs/btree_iter.c:140
Code: 90 f3 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec c0 02 00 00 48 89 54 24 28 49 89 f5 48 89 7c 24 70 <4c> 8d 35 00 2c 11 0f 65 49 8b 06 48 89 84 24 a0 02 00 00 49 bc 00
RSP: 0018:ffffc9000ba6e520 EFLAGS: 00000282
RAX: 1ffff1100518f073 RBX: 0000000000000161 RCX: ffff8880303c1e00
RDX: 0000000000000000 RSI: ffff888028c78378 RDI: ffff888028c78000
RBP: ffffc9000ba6e820 R08: ffffffff8453c7a5 R09: 0000000000000000
R10: ffffc9000ba6e9c0 R11: fffff5200174dd3a R12: 0000000000000000
R13: ffff888028c78378 R14: 1ffff1100518f072 R15: ffff888028c78378
FS: 0000000000000000(0000) GS:ffff888124fcf000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f67e14fd3b0 CR3: 0000000079034000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
bch2_btree_path_verify+0xb0/0x300 fs/bcachefs/btree_iter.c:232
bch2_btree_iter_peek_slot+0x167/0x27e0 fs/bcachefs/btree_iter.c:2736
__bch2_bkey_get_iter fs/bcachefs/btree_iter.h:591 [inline]
bch2_bkey_get_iter fs/bcachefs/btree_iter.h:605 [inline]
bch2_move_get_io_opts_one+0x518/0xa10 fs/bcachefs/move.c:470
__bch2_move_data_phys+0x1241/0x2830 fs/bcachefs/move.c:831
bch2_evacuate_bucket+0x1d9/0x2e0 fs/bcachefs/move.c:946
bch2_copygc+0x4058/0x4db0 fs/bcachefs/movinggc.c:240
bch2_copygc_thread+0x705/0xc00 fs/bcachefs/movinggc.c:398
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245