rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8041/1:b..l P5183/1:b..l P8100/1:b..l P8128/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=18309, q=632 ncpus=2)
task:udevd state:R running task stack:28328 pid:8128 tgid:8128 ppid:5183 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:debug_lockdep_rcu_enabled+0x0/0x40 kernel/rcu/update.c:319
Code: 00 00 00 eb b6 e8 80 fa ff ff eb b6 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 8b 05 56 b0 10 05 85 c0 74 20 8b 05 00 e0 10 05 85 c0
RSP: 0018:ffffc9001b607428 EFLAGS: 00000282
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000098f214b6
RDX: 0000000000000000 RSI: ffffffff8daa7ee5 RDI: ffffffff8bf2b400
RBP: ffffc9001b6074f0 R08: 00000000c06989e8 R09: 000000008c06989e
R10: 0000000000000002 R11: ffff88807752d4b0 R12: ffffffff81a96100
R13: ffffc9001b6074a8 R14: 0000000000000000 R15: ffff88807752c980
rcu_read_lock include/linux/rcupdate.h:868 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xd6/0x20b0 arch/x86/kernel/unwind_orc.c:495
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:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5657 [inline]
__kvmalloc_node_noprof+0x3ac/0xa40 mm/slub.c:7136
simple_xattr_alloc+0x46/0xa0 fs/xattr.c:1238
simple_xattr_set+0x3d/0x3e0 fs/xattr.c:1358
shmem_xattr_handler_set+0x31b/0x3b0 mm/shmem.c:4333
__vfs_setxattr+0x175/0x1e0 fs/xattr.c:200
__vfs_setxattr_noperm+0x127/0x660 fs/xattr.c:234
__vfs_setxattr_locked+0x17d/0x250 fs/xattr.c:295
vfs_setxattr+0x145/0x350 fs/xattr.c:321
do_setxattr+0x145/0x180 fs/xattr.c:636
filename_setxattr+0x16b/0x1d0 fs/xattr.c:665
path_setxattrat+0x1de/0x2a0 fs/xattr.c:713
__do_sys_lsetxattr fs/xattr.c:754 [inline]
__se_sys_lsetxattr fs/xattr.c:750 [inline]
__x64_sys_lsetxattr+0xc9/0x140 fs/xattr.c:750
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f38e471d57a
RSP: 002b:00007ffdf00c2318 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00005574f7076320 RCX: 00007f38e471d57a
RDX: 00005574f7076320 RSI: 00007f38e4daa29c RDI: 00007ffdf00c2e60
RBP: 00005574f6e338d0 R08: 0000000000000000 R09: 00005574f6e38450
R10: 000000000000001b R11: 0000000000000246 R12: 00007ffdf00c2e60
R13: 0000000000000001 R14: 00005574ef5a76d7 R15: 00005574f7071470
task:syz.4.551 state:R running task stack:25752 pid:8100 tgid:8097 ppid:5807 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872
Code: b4 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 22 bb ee 0e 0f 82 74 02 00 00 8b 35 ba eb ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 39 b4 18 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc9000475f258 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c96a0 RCX: 0000000013d622c6
RDX: 0000000000000000 RSI: ffffffff8daa7ee5 RDI: ffffffff8bf2b400
RBP: 0000000000000002 R08: 00000000accd7842 R09: 000000002accd784
R10: 0000000000000002 R11: ffff88807eceaff0 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
percpu_ref_get_many include/linux/percpu-refcount.h:202 [inline]
percpu_ref_get include/linux/percpu-refcount.h:222 [inline]
css_get include/linux/cgroup_refcnt.h:11 [inline]
css_get include/linux/cgroup_refcnt.h:8 [inline]
charge_memcg+0x130/0x230 mm/memcontrol.c:4732
__mem_cgroup_charge+0x2b/0x1e0 mm/memcontrol.c:4745
mem_cgroup_charge include/linux/memcontrol.h:663 [inline]
shmem_alloc_and_add_folio+0x50c/0xc20 mm/shmem.c:1942
shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2556
shmem_fault+0x1fe/0xa00 mm/shmem.c:2757
__do_fault+0x10d/0x490 mm/memory.c:5320
do_read_fault mm/memory.c:5755 [inline]
do_fault+0xae4/0x1ad0 mm/memory.c:5889
do_pte_missing mm/memory.c:4401 [inline]
handle_pte_fault mm/memory.c:6273 [inline]
__handle_mm_fault+0x1919/0x2bb0 mm/memory.c:6411
handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580
do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0010:rep_movs_alternative+0x30/0x90 arch/x86/lib/copy_user_64.S:60
Code: 83 f9 08 73 25 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 <48> 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 db 83 f9 08
RSP: 0018:ffffc9000475fa48 EFLAGS: 00050206
RAX: 0000000000000001 RBX: 000020000029d000 RCX: 0000000000000038
RDX: fffff520008ebf5a RSI: 000020000029d000 RDI: ffffc9000475fa98
RBP: 0000000000000038 R08: 0000000000000001 R09: fffff520008ebf59
R10: ffffc9000475facf R11: ffff88807eceaff0 R12: 0000000000000000
R13: ffffc9000475fa98 R14: ffffc9000475fb80 R15: ffffc9000475fa98
copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline]
_inline_copy_from_user include/linux/uaccess.h:185 [inline]
_copy_from_user+0x98/0xd0 lib/usercopy.c:18
copy_from_user include/linux/uaccess.h:223 [inline]
copy_msghdr_from_user+0x98/0x160 net/socket.c:2522
recvmsg_copy_msghdr net/socket.c:2778 [inline]
___sys_recvmsg+0xdb/0x1a0 net/socket.c:2850
do_recvmmsg+0x2fe/0x750 net/socket.c:2949
__sys_recvmmsg net/socket.c:3023 [inline]
__do_sys_recvmmsg net/socket.c:3046 [inline]
__se_sys_recvmmsg net/socket.c:3039 [inline]
__x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3039
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0d6dd8f749
RSP: 002b:00007f0d6ec9e038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f0d6dfe6090 RCX: 00007f0d6dd8f749
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f0d6de13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0d6dfe6128 R14: 00007f0d6dfe6090 R15: 00007ffdec2ac8a8
task:udevd state:R running task stack:26264 pid:5183 tgid:5183 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7047
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:194
sock_def_readable+0x15b/0x5d0 net/core/sock.c:3611
__netlink_sendskb net/netlink/af_netlink.c:1263 [inline]
netlink_sendskb net/netlink/af_netlink.c:1269 [inline]
netlink_unicast+0x75f/0x870 net/netlink/af_netlink.c:1359
netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592
___sys_sendmsg+0x134/0x1d0 net/socket.c:2646
__sys_sendmsg+0x16d/0x220 net/socket.c:2678
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f38e46a7407
RSP: 002b:00007ffdf00c33d0 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f38e4d4c880 RCX: 00007f38e46a7407
RDX: 0000000000000000 RSI: 00007ffdf00c3430 RDI: 0000000000000004
RBP: 00005574f70754d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000088
R13: 00005574f6e35d80 R14: 0000000000000000 R15: 0000000000000000
task:syz.3.531 state:R running task stack:25944 pid:8041 tgid:8024 ppid:5816 task_flags:0x40044c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:228 [inline]
RIP: 0010:unwind_next_frame+0x1d6/0x20b0 arch/x86/kernel/unwind_orc.c:510
Code: 13 7c 8b 0f 83 4e 02 00 00 8b 35 55 0d 6b 0c 4c 89 f8 48 2d 00 00 00 81 48 c1 e8 08 8d 56 ff 41 89 c3 39 d0 0f 83 17 16 00 00 <48> ba 00 00 00 00 00 fc ff df 89 c1 48 8d 3c 8d 4c 9d dc 91 49 89
RSP: 0018:ffffc90004b2ee20 EFLAGS: 00000283
RAX: 0000000000010d15 RBX: 0000000000000001 RCX: 1ffff92000965ddb
RDX: 00000000000a7c14 RSI: 00000000000a7c15 RDI: ffffffff8dd7bf28
RBP: ffffc90004b2eed8 R08: 00000000accd7842 R09: 000000002accd784
R10: 0000000000000002 R11: 0000000000010d15 R12: ffffc90004b2eee0
R13: ffffc90004b2ee90 R14: ffffc90004b2eec5 R15: ffffffff820d15f7
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1406 [inline]
free_unref_folios+0xa22/0x1610 mm/page_alloc.c:3000
folios_put_refs+0x4be/0x750 mm/swap.c:1002
free_pages_and_swap_cache+0x245/0x4a0 mm/swap_state.c:355
__tlb_batch_free_encoded_pages+0xf9/0x290 mm/mmu_gather.c:136
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu+0xe9/0x5a0 mm/mmu_gather.c:404
zap_pte_range mm/memory.c:1893 [inline]
zap_pmd_range mm/memory.c:1946 [inline]
zap_pud_range mm/memory.c:1975 [inline]
zap_p4d_range mm/memory.c:1996 [inline]
unmap_page_range+0x1e64/0x43c0 mm/memory.c:2017
unmap_single_vma+0x153/0x240 mm/memory.c:2059
unmap_vmas+0x218/0x470 mm/memory.c:2101
exit_mmap+0x1b0/0xb60 mm/mmap.c:1277
__mmput+0x12a/0x410 kernel/fork.c:1173
mmput+0x62/0x70 kernel/fork.c:1196
exit_mm kernel/exit.c:581 [inline]
do_exit+0x7d7/0x2bd0 kernel/exit.c:959
do_group_exit+0xd3/0x2a0 kernel/exit.c:1112
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x8c/0x540 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1d7038f749
RSP: 002b:00007f1d71148038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: 000000000003ffff RBX: 00007f1d705e6090 RCX: 00007f1d7038f749
RDX: 00000000080002c1 RSI: 0000200000000040 RDI: 0000000000000004
RBP: 00007f1d70413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1d705e6128 R14: 00007f1d705e6090 R15: 00007ffd0a6d8158
rcu: rcu_preempt kthread starved for 10663 jiffies! g18309 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:27432 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8125 Comm: vhost-8123 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:__sanitizer_cov_trace_const_cmp1+0x0/0x20 kernel/kcov.c:299
Code: 0c 24 48 89 f2 48 89 fe bf 06 00 00 00 e9 b8 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 0c 24 40 0f b6 d6 40 0f b6 f7 bf 01 00 00 00 e9
RSP: 0018:ffffc9000472fbf0 EFLAGS: 00000246
RAX: 0000000000000070 RBX: 1ffff920008e5f8c RCX: ffffc9001a524000
RDX: 0000000000100000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000fffffff9 R11: ffff888031480b30 R12: ffff888058ce4c10
R13: 00000000ffffffff R14: ffff888058ce0000 R15: 0000000000000000
FS: 00007f696843e6c0(0000) GS:ffff8881249f5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000029d000 CR3: 0000000030227000 CR4: 00000000003526f0
Call Trace:
vhost_vsock_handle_tx_kick+0x8cc/0xdb0 drivers/vhost/vsock.c:552
vhost_run_work_list+0x18b/0x230 drivers/vhost/vhost.c:454
vhost_task_fn+0x165/0x460 kernel/vhost_task.c:49
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246