rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16866/1:b..l P16887/1:b..l P14087/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=100085, q=508 ncpus=2)
task:syz-executor state:R running task stack:20832 pid:14087 tgid:14087 ppid:14078 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x2d8/0x3b0 kernel/locking/lockdep.c:5893
Code: 34 e2 10 00 00 00 00 eb b5 e8 64 6f bb 09 f7 c3 00 02 00 00 74 b9 65 48 8b 05 74 ee e1 10 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 44 1f 72 ff cc 48 8d 3d 11 49 e7
RSP: 0018:ffffc900034ff760 EFLAGS: 00000286
RAX: add086c5e7aff500 RBX: 0000000000000202 RCX: 0000000000000046
RDX: 0000000000000000 RSI: ffffffff8d975f94 RDI: ffffffff8bc083e0
RBP: ffff888020aa4830 R08: ffffc900034ff8b8 R09: ffffc900034ff918
R10: dffffc0000000000 R11: fffff5200069ff25 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8df41aa0 R15: ffff888020aa3d00
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x1ab1/0x23d0 arch/x86/kernel/unwind_orc.c:695
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:773
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_lru_noprof+0x36c/0x6e0 mm/slub.c:5282
__d_alloc+0x37/0x6f0 fs/dcache.c:1730
d_alloc_pseudo+0x21/0xc0 fs/dcache.c:1861
alloc_path_pseudo fs/file_table.c:363 [inline]
alloc_file_pseudo+0xcc/0x210 fs/file_table.c:379
sock_alloc_file+0xb8/0x2e0 net/socket.c:483
sock_map_fd net/socket.c:513 [inline]
__sys_socket+0x13d/0x1b0 net/socket.c:1756
__do_sys_socket net/socket.c:1761 [inline]
__se_sys_socket net/socket.c:1759 [inline]
__x64_sys_socket+0x7a/0x90 net/socket.c:1759
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8b37f91667
RSP: 002b:00007fff10382348 EFLAGS: 00000206 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f8b37f91667
RDX: 0000000000000006 RSI: 0000000000000001 RDI: 000000000000000a
RBP: 00007fff10382a7c R08: 00007fff1038236c R09: 0079746972756365
R10: 00007fff103823d0 R11: 0000000000000206 R12: 00007f8b381b5ca0
R13: 00000000000927c0 R14: 0000000000149f93 R15: 00007f8b381b7e60
task:syz-executor state:R running task stack:27552 pid:16887 tgid:16887 ppid:15502 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
RIP: 0010:seqcount_lockdep_reader_access+0xec/0x100 include/linux/seqlock.h:75
Code: 00 75 11 e8 46 c4 83 ff 4d 85 ff 75 16 e8 3c c4 83 ff eb 15 e8 35 c4 83 ff e8 70 5d 1c 09 4d 85 ff 74 ea e8 26 c4 83 ff fb 5b <41> 5e 41 5f e9 66 0d d3 fe cc 66 2e 0f 1f 84 00 00 00 00 00 90 90
RSP: 0018:ffffc90004ebfa20 EFLAGS: 00000293
RAX: ffffffff823d339a RBX: ffff8880248e64c0 RCX: ffff8880248e5b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88807a445798 R08: ffffffff8f822277 R09: 1ffffffff1f0444e
R10: dffffc0000000000 R11: fffffbfff1f0444f R12: ffff888045174420
R13: ffff88807a445708 R14: ffffffff823d0004 R15: 0000000000000200
read_seqbegin include/linux/seqlock.h:836 [inline]
path_init+0x4f4/0x1330 fs/namei.c:2666
path_parentat fs/namei.c:2792 [inline]
__filename_parentat+0x23b/0x670 fs/namei.c:2817
filename_parentat fs/namei.c:2835 [inline]
filename_create+0xcf/0x360 fs/namei.c:4860
do_symlinkat+0x120/0x3c0 fs/namei.c:5534
__do_sys_symlinkat fs/namei.c:5562 [inline]
__se_sys_symlinkat fs/namei.c:5559 [inline]
__x64_sys_symlinkat+0x95/0xb0 fs/namei.c:5559
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa0a258ecc7
RSP: 002b:00007fffd6a3e358 EFLAGS: 00000206 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa0a258ecc7
RDX: 00007fa0a26158c3 RSI: 00000000ffffff9c RDI: 00007fa0a2614390
RBP: 00007fffd6a3e39c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 000000000000004b
R13: 00000000000927c0 R14: 0000000000149f3f R15: 00007fffd6a3e3f0
task:syz.7.2392 state:R running task stack:25120 pid:16866 tgid:16865 ppid:16430 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:229 [inline]
RIP: 0010:unwind_next_frame+0x223/0x23d0 arch/x86/kernel/unwind_orc.c:510
Code: 86 78 04 00 00 44 89 f8 4c 8d 2c 85 98 1c c2 90 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 48 89 eb 0f 85 2c 1c 00 00 45 8b 6d 00 <44> 89 f8 ff c0 48 8d 2c 85 98 1c c2 90 48 89 e8 48 c1 e8 03 0f b6
RSP: 0018:ffffc90004dfeeb8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000080000000
RDX: 00000000000a5d52 RSI: ffffffff8bc083c0 RDI: ffffffff8bc08380
RBP: dffffc0000000000 R08: ffffffff8173fd65 R09: ffffffff8df41aa0
R10: dffffc0000000000 R11: ffffffff81acf3d0 R12: ffffffff824bb6a0
R13: 0000000000045c7c R14: ffffc90004dfef88 R15: 0000000000014bb6
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5270
alloc_buffer_head+0x2a/0x270 fs/buffer.c:3025
folio_alloc_buffers+0x32d/0x640 fs/buffer.c:935
create_empty_buffers+0x3a/0x530 fs/buffer.c:1691
__block_write_begin_int+0x3b1/0x1900 fs/buffer.c:2126
block_write_begin+0x8d/0x120 fs/buffer.c:2256
udf_write_begin+0x118/0x270 fs/udf/inode.c:262
generic_perform_write+0x2c5/0x900 mm/filemap.c:4314
udf_file_write_iter+0x2d5/0x6c0 fs/udf/file.c:111
iter_file_splice_write+0x972/0x10b0 fs/splice.c:738
do_splice_from fs/splice.c:938 [inline]
direct_splice_actor+0x101/0x160 fs/splice.c:1161
splice_direct_to_actor+0x5a8/0xcc0 fs/splice.c:1105
do_splice_direct_actor fs/splice.c:1204 [inline]
do_splice_direct+0x181/0x270 fs/splice.c:1230
do_sendfile+0x4da/0x7e0 fs/read_write.c:1370
__do_sys_sendfile64 fs/read_write.c:1431 [inline]
__se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f45d318f749
RSP: 002b:00007f45d3fcd038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f45d33e5fa0 RCX: 00007f45d318f749
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000008
RBP: 00007f45d3213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0001000000201005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f45d33e6038 R14: 00007f45d33e5fa0 R15: 00007fff2d5b4048
rcu: rcu_preempt kthread starved for 10628 jiffies! g100085 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:R running task stack:27744 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 3e b4 b6 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 73 c1 0e 00 f3 0f 1e fa fb f4 13 b4 b6 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8dc07dc0 EFLAGS: 000002c2
RAX: 0000000002dfea3b RBX: ffffffff819713ee RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d79207b RDI: ffffffff8bc083e0
RBP: ffffffff8dc07eb0 R08: ffff8880b86336db R09: 1ffff110170c66db
R10: dffffc0000000000 R11: ffffed10170c66dc R12: ffffffff8f822270
R13: 1ffffffff1b92a68 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125e1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa0a2519000 CR3: 000000009b684000 CR4: 0000000000350ef0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
rest_init+0x2de/0x300 init/main.c:757
start_kernel+0x381/0x3d0 init/main.c:1206
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147