rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15428/1:b..l P28928/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=180473, q=2602 ncpus=2)
task:udevd state:R running task stack:27544 pid:28928 tgid:28928 ppid:5235 task_flags:0x40014c flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288
irqentry_exit+0x36/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872
Code: cd 3e 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 a2 3e 14 0f 0f 82 74 02 00 00 8b 35 3a 70 14 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 f9 cc 3e 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc900043cf6c0 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e5c10e0 RCX: 00000000e7a1e39a
RDX: 0000000000000000 RSI: ffffffff8de296cd RDI: ffffffff8c163180
RBP: 0000000000000002 R08: d42ef163819603fb R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
__unwind_start+0x45f/0x7f0 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0x73/0x100 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:405
kmalloc_noprof include/linux/slab.h:905 [inline]
slab_free_hook mm/slub.c:2374 [inline]
slab_free mm/slub.c:4695 [inline]
kmem_cache_free+0x142/0x4d0 mm/slub.c:4797
exit_mmap+0x511/0xb90 mm/mmap.c:1305
__mmput+0x12a/0x410 kernel/fork.c:1130
mmput+0x62/0x70 kernel/fork.c:1152
exit_mm kernel/exit.c:582 [inline]
do_exit+0x7c7/0x2bf0 kernel/exit.c:949
do_group_exit+0xd3/0x2a0 kernel/exit.c:1102
__do_sys_exit_group kernel/exit.c:1113 [inline]
__se_sys_exit_group kernel/exit.c:1111 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1111
x64_sys_call+0x14fa/0x1720 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f781a4f16c5
RSP: 002b:00007ffded297668 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000559192022f80 RCX: 00007f781a4f16c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 0000559191ffe910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffded2976b0 R14: 0000000000000000 R15: 0000000000000000
task:syz.1.5507 state:R running task stack:25912 pid:15428 tgid:15427 ppid:28671 task_flags:0x400040 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288
irqentry_exit+0x36/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872
Code: cd 3e 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 a2 3e 14 0f 0f 82 74 02 00 00 8b 35 3a 70 14 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 f9 cc 3e 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc90003277300 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e5c10e0 RCX: 000000001d4c1aa9
RDX: 0000000000000000 RSI: ffffffff8de296cd RDI: ffffffff8c163180
RBP: 0000000000000002 R08: 0064b6fb78cdd7c9 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:243 [inline]
__kasan_slab_free+0x60/0x70 mm/kasan/common.c:275
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2422 [inline]
slab_free mm/slub.c:4695 [inline]
kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4797
free_buffer_head+0x4e/0x110 fs/buffer.c:3041
try_to_free_buffers+0x1c4/0x2d0 fs/buffer.c:2982
filemap_release_folio+0x219/0x280 mm/filemap.c:4356
block_invalidate_folio+0x508/0x600 fs/buffer.c:1674
folio_invalidate mm/truncate.c:140 [inline]
truncate_cleanup_folio+0x2f3/0x490 mm/truncate.c:160
truncate_inode_pages_range+0x24e/0xe50 mm/truncate.c:379
kill_bdev block/bdev.c:91 [inline]
blkdev_flush_mapping+0xfb/0x290 block/bdev.c:712
blkdev_put_whole+0xc4/0xf0 block/bdev.c:719
bdev_release+0x47e/0x6d0 block/bdev.c:1144
blkdev_release+0x15/0x20 block/fops.c:699
__fput+0x402/0xb70 fs/file_table.c:468
task_work_run+0x14d/0x240 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x3f6/0x490 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f32a398ebe9
RSP: 002b:00007f32a484f038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f32a3bc5fa0 RCX: 00007f32a398ebe9
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000002
RBP: 00007f32a3a11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f32a3bc6038 R14: 00007f32a3bc5fa0 R15: 00007ffec0f29e78
rcu: rcu_preempt kthread starved for 9618 jiffies! g180473 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27784 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G U syzkaller #0 PREEMPT(full)
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 8c 64 02 c3 cc cc cc cc 0f 1f 00 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 e3 d1 18 00 fb f4 7c 09 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df8 EFLAGS: 000002c6
RAX: 00000000010200eb RBX: 0000000000000001 RCX: ffffffff8b913bf9
RDX: 0000000000000000 RSI: ffffffff8de4eb79 RDI: ffffffff8c163180
RBP: ffffed1003c56b40 R08: 0000000000000001 R09: ffffed10170a6655
R10: ffff8880b85332ab R11: 0000000000000000 R12: 0000000000000001
R13: ffff88801e2b5a00 R14: ffffffff90aba190 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881247bd000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2059c4ac3e CR3: 0000000028948000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x391/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428
start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x148