rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (0 ticks this GP) idle=c40c/1/0x4000000000000000 softirq=81659/81659 fqs=1
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5820/1:b..l P15473/2:b..l
rcu: (detected by 0, t=10502 jiffies, g=77293, q=428 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 15566 Comm: syz.0.2009 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:mark_lock+0x3a/0xa20 kernel/locking/lockdep.c:4731
Code: 89 f4 53 48 83 e4 f0 48 83 ec 70 65 48 8b 1d d5 64 2e 12 48 89 5c 24 68 89 d3 83 fa 08 74 6d 41 be 01 00 00 00 89 d9 41 d3 e6 <4d> 63 f6 41 0f b7 44 24 20 66 25 ff 1f 0f b7 c0 48 0f a3 05 fe 3b
RSP: 0018:ffffc90000a08b50 EFLAGS: 00000093
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff888035108bb8 RDI: ffff888035108000
RBP: ffffc90000a08bf0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffff888035108bb8
R13: ffff888035108000 R14: 0000000000000001 R15: 0000000000000002
FS: 00007f9b622646c0(0000) GS:ffff8881243e7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9b61617dac CR3: 000000003cd42000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
mark_usage kernel/locking/lockdep.c:4639 [inline]
__lock_acquire+0x10ff/0x2630 kernel/locking/lockdep.c:5191
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x1b1/0x370 kernel/locking/lockdep.c:5825
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:166
debug_object_activate+0x144/0x490 lib/debugobjects.c:835
debug_hrtimer_activate kernel/time/hrtimer.c:485 [inline]
debug_activate kernel/time/hrtimer.c:528 [inline]
enqueue_hrtimer+0x75/0x2f0 kernel/time/hrtimer.c:1109
__run_hrtimer kernel/time/hrtimer.c:1946 [inline]
__hrtimer_run_queues+0x73d/0xa00 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x460 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:198
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 66 42 49 f6 48 89 df e8 3e 92 49 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 25 67 39 f6 65 8b 05 3e 6f 77 08 85 c0 74 16 5b
RSP: 0018:ffffc9000367fd78 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffffff9b235118 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8df562a9 RDI: ffffffff8c1c1300
RBP: 0000000000000283 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000400000000 R12: 1ffff920006cffb6
R13: 000000009238a40f R14: 000000009238a40f R15: 0000000000000000
class_raw_spinlock_irqsave_destructor include/linux/spinlock.h:571 [inline]
do_settimeofday64+0x326/0x4d0 kernel/time/timekeeping.c:1584
do_sys_settimeofday64+0x1dc/0x260 kernel/time/time.c:195
__do_sys_clock_settime kernel/time/posix-timers.c:1124 [inline]
__se_sys_clock_settime kernel/time/posix-timers.c:1108 [inline]
__x64_sys_clock_settime+0x1c1/0x2a0 kernel/time/posix-timers.c:1108
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9b6139c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9b62264028 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 00007f9b61615fa0 RCX: 00007f9b6139c819
RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0100000000000000
RBP: 00007f9b61432c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9b61616038 R14: 00007f9b61615fa0 R15: 00007ffc0192f5d8
task:udevd state:R running task stack:27240 pid:15473 tgid:15473 ppid:5194 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x10e9/0x6820 kernel/sched/core.c:7188
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7512
irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:476 [inline]
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline]
irqentry_exit+0x1fe/0x790 kernel/entry/common.c:164
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:av_hash security/selinux/include/hash.h:32 [inline]
RIP: 0010:avc_hash security/selinux/avc.c:128 [inline]
RIP: 0010:avc_search_node security/selinux/avc.c:527 [inline]
RIP: 0010:avc_lookup+0x21/0x240 security/selinux/avc.c:558
Code: 90 90 90 90 90 90 90 90 90 41 57 41 89 f7 41 56 41 89 d6 41 55 41 89 fd 41 54 55 53 89 d3 e8 46 ca 5b fd 65 ff 05 3f 49 67 0f <41> 69 c5 51 2d 9e cc c1 c0 0f 69 c0 93 35 87 1b c1 c0 0d 8d 94 80
RSP: 0018:ffffc90003977988 EFLAGS: 00000203
RAX: 0000000000000000 RBX: 0000000000000008 RCX: ffffffff84adecd1
RDX: ffff888041180000 RSI: ffffffff84adaf3a RDI: 0000000000000046
RBP: 0000000000000008 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000046 R14: 0000000000000008 R15: 0000000000000022
avc_has_perm_noaudit+0x97/0x3b0 security/selinux/avc.c:1157
selinux_inode_permission+0x81c/0x1160 security/selinux/hooks.c:3284
security_inode_permission+0xda/0x250 security/security.c:1842
lookup_inode_permission_may_exec fs/namei.c:693 [inline]
may_lookup fs/namei.c:1957 [inline]
link_path_walk+0x2a5/0x1cc0 fs/namei.c:2600
path_parentat fs/namei.c:2856 [inline]
__filename_parentat+0x213/0x740 fs/namei.c:2880
filename_parentat fs/namei.c:2898 [inline]
filename_unlinkat+0xf7/0x730 fs/namei.c:5537
__do_sys_unlink fs/namei.c:5603 [inline]
__se_sys_unlink fs/namei.c:5600 [inline]
__x64_sys_unlink+0x46/0x70 fs/namei.c:5600
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7027315937
RSP: 002b:00007ffe5385bad8 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007ffe5385bb00 RCX: 00007f7027315937
RDX: fffffffffffffe68 RSI: 00007ffe5385bf00 RDI: 0000561fc81328f0
RBP: 0000000000000000 R08: 0000561fc812b1d0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000561fc8144020
R13: 00007ffe5385c700 R14: 0000000000000000 R15: 00007ffe5385bf00
task:syz-executor state:R running task stack:23352 pid:5820 tgid:5820 ppid:5818 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x10e9/0x6820 kernel/sched/core.c:7188
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7512
irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:476 [inline]
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline]
irqentry_exit+0x1fe/0x790 kernel/entry/common.c:164
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:58 [inline]
RIP: 0010:stack_access_ok+0x28/0x1d0 arch/x86/kernel/unwind_orc.c:409
Code: 90 90 48 b8 00 00 00 00 00 fc ff df 41 55 41 54 49 89 d4 48 89 fa 55 48 c1 ea 03 48 89 f5 53 48 89 fb 48 83 ec 08 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e 3f 01 00 00 8b 13 85 d2 74 65 48 b8 00 00
RSP: 0018:ffffc900037df5a8 EFLAGS: 00000292
RAX: 0000000000000000 RBX: ffffc900037df648 RCX: ffffffff918a59b8
RDX: 1ffff920006fbec9 RSI: ffffc900037df9c8 RDI: ffffc900037df648
RBP: ffffc900037df9c8 R08: ffffffff918a59bc R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000017702 R12: 0000000000000008
R13: ffffc900037df648 R14: ffffc900037df9d0 R15: ffffc900037df67c
deref_stack_reg arch/x86/kernel/unwind_orc.c:419 [inline]
unwind_next_frame+0xcf5/0x2090 arch/x86/kernel/unwind_orc.c:614
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 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:5295 [inline]
__kmalloc_noprof+0x301/0x850 mm/slub.c:5307
kmalloc_noprof include/linux/slab.h:954 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
tomoyo_encode2+0xfb/0x3c0 security/tomoyo/realpath.c:45
tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80
tomoyo_realpath_from_path+0x18c/0x690 security/tomoyo/realpath.c:283
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x276/0x460 security/tomoyo/file.c:827
tomoyo_path_unlink+0x91/0xe0 security/tomoyo/tomoyo.c:162
security_path_unlink+0x145/0x2b0 security/security.c:1483
filename_unlinkat+0x316/0x730 fs/namei.c:5565
__do_sys_unlink fs/namei.c:5603 [inline]
__se_sys_unlink fs/namei.c:5600 [inline]
__x64_sys_unlink+0x46/0x70 fs/namei.c:5600
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feb9a59b907
RSP: 002b:00007ffe3b4810e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007feb9a59b907
RDX: 00007ffe3b481110 RSI: 00007ffe3b4811a0 RDI: 00007ffe3b4811a0
RBP: 00007ffe3b4811a0 R08: 00007ffe3b4821a0 R09: 00000000ffffffff
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffe3b482230
R13: 00007feb9a632048 R14: 00000000000b4db5 R15: 00007ffe3b482270
rcu: rcu_preempt kthread starved for 10500 jiffies! g77293 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:28840 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x10e9/0x6820 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7282
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 15564 Comm: modprobe Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x589/0x1700 kernel/smp.c:892
Code: b8 00 00 00 00 00 fc ff df 48 8b 54 24 08 49 89 d5 49 89 d4 49 c1 ed 03 41 83 e4 07 49 01 c5 41 83 c4 03 e8 19 80 0c 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 63 0f 00 00 8b 45 08 31
RSP: 0018:ffffc900047078a8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81fcf98d
RDX: ffff88805bb10000 RSI: ffffffff81fcf967 RDI: ffff88805bb10000
RBP: ffff8880b8540f40 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed10170a81e9 R14: 0000000000000001 R15: ffff8880b843c5c0
FS: 0000000000000000(0000) GS:ffff8881242e7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000db6030 CR3: 00000000873fc000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1057
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x45f/0x16f0 arch/x86/mm/tlb.c:1451
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:509 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:499 [inline]
tlb_flush_mmu mm/mmu_gather.c:423 [inline]
tlb_finish_mmu+0x3fe/0x810 mm/mmu_gather.c:549
exit_mmap+0x454/0xa10 mm/mmap.c:1313
__mmput+0x12a/0x410 kernel/fork.c:1178
mmput+0x67/0x80 kernel/fork.c:1201
exit_mm kernel/exit.c:581 [inline]
do_exit+0x833/0x2a60 kernel/exit.c:963
do_group_exit+0xd5/0x2a0 kernel/exit.c:1117
__do_sys_exit_group kernel/exit.c:1128 [inline]
__se_sys_exit_group kernel/exit.c:1126 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1126
x64_sys_call+0x102c/0x1530 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe1156696c5
Code: Unable to access opcode bytes at 0x7fe11566969b.
RSP: 002b:00007fff82785e78 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fe11576afe8 RCX: 00007fe1156696c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000001
RBP: 0000000000000001 R08: 00007fff82785e08 R09: 0000000000000000
R10: 00007fff82785ca0 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fe115769680 R15: 00007fe11576b000