INFO: task syz.1.17:6038 blocked for more than 143 seconds.
Not tainted 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.17 state:D stack:28744 pid:6038 tgid:6003 ppid:5819 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578
inode_lock include/linux/fs.h:867 [inline]
open_last_lookups fs/namei.c:3797 [inline]
path_openat+0x8da/0x3830 fs/namei.c:4036
do_filp_open+0x1fa/0x410 fs/namei.c:4066
do_sys_openat2+0x121/0x1c0 fs/open.c:1429
do_sys_open fs/open.c:1444 [inline]
__do_sys_openat fs/open.c:1460 [inline]
__se_sys_openat fs/open.c:1455 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1455
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9e6098e969
RSP: 002b:00007f9e6189e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f9e60bb6080 RCX: 00007f9e6098e969
RDX: 0000000000008042 RSI: 00002000000000c0 RDI: ffffffffffffff9c
RBP: 00007f9e60a10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f9e60bb6080 R15: 00007ffe8ca9ec68
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
2 locks held by kworker/u8:8/3443:
2 locks held by getty/5584:
#0: ffff888033be20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036cb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/5833:
#0: ffff8880723ce0e0 (&type->s_umount_key#75){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline]
#0: ffff8880723ce0e0 (&type->s_umount_key#75){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff8880723ce0e0 (&type->s_umount_key#75){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505
#1: ffffffff8df41200 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3774
1 lock held by syz-executor/5836:
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998
5 locks held by syz.1.17/6004:
#0: ffff888054b7c420 (sb_writers#17){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
#1: ffff8880594108e0 (&sb->s_type->i_mutex_key#26){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#1: ffff8880594108e0 (&sb->s_type->i_mutex_key#26){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline]
#1: ffff8880594108e0 (&sb->s_type->i_mutex_key#26){+.+.}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036
#2: ffff888059410cc8 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x2f2/0xb90 fs/bcachefs/fs.c:569
#3: ffff888057f04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#3: ffff888057f04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#3: ffff888057f04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3202
#4: ffff888057f26590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179
2 locks held by syz.1.17/6038:
#0: ffff888054b7c420 (sb_writers#17){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
#1: ffff8880594108e0 (&sb->s_type->i_mutex_key#26){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#1: ffff8880594108e0 (&sb->s_type->i_mutex_key#26){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline]
#1: ffff8880594108e0 (&sb->s_type->i_mutex_key#26){+.+.}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036
2 locks held by bch-copygc/loop/6034:
3 locks held by syz.5.255/8031:
1 lock held by dhcpcd-run-hook/8055:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/0x8a0 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8031 Comm: syz.5.255 Not tainted 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:get_running_cputimer include/linux/sched/cputime.h:79 [inline]
RIP: 0010:account_group_exec_runtime include/linux/sched/cputime.h:164 [inline]
RIP: 0010:update_curr_task+0xa5/0x330 kernel/sched/fair.c:1172
Code: 4c 89 ff e8 fd 4e 8c 00 4d 8b 2f 4d 8d bd 98 01 00 00 4c 89 f8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 93 01 00 00 41 83 3f 00 <74> 3c 4d 8d be 28 09 00 00 4c 89 f8 48 c1 e8 03 42 80 3c 20 00 74
RSP: 0018:ffffc9000afbece0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000100f0e RCX: ba011d33e989bf00
RDX: 0000000000000000 RSI: ffffffff8bc0fe40 RDI: ffffffff8bc0fe00
RBP: 000000027ecaf539 R08: ffffffff8f7daf77 R09: 1ffffffff1efb5ee
R10: dffffc0000000000 R11: fffffbfff1efb5ef R12: dffffc0000000000
R13: ffff88801e39f2c0 R14: ffff888024b0da00 R15: ffff88801e39f458
FS: 00007f8a911ea6c0(0000) GS:ffff8881261fe000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555583e17608 CR3: 000000003090e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
update_curr+0x380/0x8b0 kernel/sched/fair.c:1247
put_prev_entity+0x41/0x230 kernel/sched/fair.c:5617
pick_next_task_fair+0x7e3/0xba0 kernel/sched/fair.c:8910
__pick_next_task+0xe4/0x450 kernel/sched/core.c:6032
pick_next_task kernel/sched/core.c:-1 [inline]
__schedule+0x6f7/0x4c70 kernel/sched/core.c:6720
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7090
irqentry_exit+0x6f/0x90 kernel/entry/common.c:354
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:stack_depot_save_flags+0x44c/0x910 lib/stackdepot.c:681
Code: 8e 4c 89 e6 e8 c5 55 6b 06 4d 85 f6 74 17 f7 44 24 0c 00 0c 00 00 74 3d 4c 89 f7 be 02 00 00 00 e8 99 c5 2c fd 4d 85 ed 74 57 <41> 8b 45 18 65 48 8b 0d f8 db 8b 0d 48 3b 4c 24 30 0f 85 05 04 00
RSP: 0018:ffffc9000afbf210 EFLAGS: 00000282
RAX: 000000000000000e RBX: 0000000000140cca RCX: ffffffff81000130
RDX: 00000000e03622c1 RSI: 0000000000000001 RDI: 000000009af72819
RBP: 00000000e488e3ed R08: 00000000186823ec R09: 00000000291c6d10
R10: 000000000000000e R11: ffffffff81ce9356 R12: 0000000000000001
R13: ffff888079eec680 R14: ffffc9000afbf2c0 R15: ffff88823b6e3ed0
save_stack+0x105/0x1f0 mm/page_owner.c:157
__set_page_owner+0x8d/0x4a0 mm/page_owner.c:329
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718
prep_new_page mm/page_alloc.c:1726 [inline]
get_page_from_freelist+0x21c7/0x22a0 mm/page_alloc.c:3688
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301
folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2320
shmem_alloc_folio mm/shmem.c:1854 [inline]
shmem_alloc_and_add_folio+0x447/0xf60 mm/shmem.c:1893
shmem_get_folio_gfp+0x597/0x15f0 mm/shmem.c:2533
shmem_get_folio mm/shmem.c:2639 [inline]
shmem_write_begin+0xf7/0x2b0 mm/shmem.c:3289
generic_perform_write+0x2c4/0x910 mm/filemap.c:4103
shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3464
new_sync_write fs/read_write.c:591 [inline]
vfs_write+0x548/0xa90 fs/read_write.c:684
ksys_write+0x145/0x250 fs/read_write.c:736
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8a9038d41f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007f8a911e9df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f8a9038d41f
RDX: 0000000001000000 RSI: 00007f8a85c00000 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005108
R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000005
R13: 00007f8a911e9ef0 R14: 00007f8a911e9eb0 R15: 00007f8a85c00000