rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=84bc/1/0x4000000000000000 softirq=92549/92557 fqs=15
(detected by 0, t=10505 jiffies, g=126581, q=828 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3638 Comm: udevd Not tainted 6.1.148-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__lock_release kernel/locking/lockdep.c:5346 [inline]
RIP: 0010:lock_release+0x23a/0x910 kernel/locking/lockdep.c:5682
Code: 44 89 7c 24 3c 44 89 fa 85 c0 0f 84 d9 01 00 00 4d 85 e4 0f 84 01 03 00 00 4d 8d 74 24 24 4c 89 f0 48 c1 e8 03 42 0f b6 04 28 <84> c0 0f 85 af 04 00 00 41 83 3e 00 0f 85 c0 03 00 00 4d 8d 74 24
RSP: 0018:ffffc900001e0b60 EFLAGS: 00000807
RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000000001
RDX: 0000000000000001 RSI: ffff8880b8f2a598 RDI: ffff88807b2d28c8
RBP: ffffc900001e0c70 R08: dffffc0000000000 R09: fffffbfff1c3ea96
R10: fffffbfff1c3ea96 R11: 1ffffffff1c3ea95 R12: ffff88807b2d28c8
R13: dffffc0000000000 R14: ffff88807b2d28ec R15: 0000000000000001
FS: 00007f1c5b5b8880(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f71c9250440 CR3: 000000007b759000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000c DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
_raw_spin_unlock_irqrestore+0x6d/0x100 kernel/locking/spinlock.c:194
__run_hrtimer kernel/time/hrtimer.c:1748 [inline]
__hrtimer_run_queues+0x446/0xd60 kernel/time/hrtimer.c:1816
hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1878
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:65
Code: 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa <4c> 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01
RSP: 0018:ffffc900032d7148 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffc900032d7228 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc900032d7288
RBP: ffffffff8eaade8a R08: dffffc0000000000 R09: ffffc900032d7278
R10: fffff5200065ae51 R11: 1ffff9200065ae4f R12: 1ffff9200065ae46
R13: dffffc0000000000 R14: ffffc900032d7278 R15: ffffc900032d725d
unwind_next_frame+0xb8a/0x20b0 arch/x86/kernel/unwind_orc.c:546
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
____kasan_kmalloc mm/kasan/common.c:374 [inline]
__kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383
kasan_kmalloc include/linux/kasan.h:211 [inline]
__do_kmalloc_node mm/slab_common.c:936 [inline]
__kmalloc+0xb0/0x240 mm/slab_common.c:949
kmalloc include/linux/slab.h:568 [inline]
tomoyo_realpath_from_path+0xdf/0x5d0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_check_open_permission+0x1aa/0x380 security/tomoyo/file.c:771
security_file_open+0x5e/0xa0 security/security.c:1681
do_dentry_open+0x305/0x10d0 fs/open.c:869
do_open fs/namei.c:3626 [inline]
path_openat+0x25c6/0x2e70 fs/namei.c:3783
do_filp_open+0x1c1/0x3c0 fs/namei.c:3810
do_sys_openat2+0x142/0x490 fs/open.c:1318
do_sys_open fs/open.c:1334 [inline]
__do_sys_openat fs/open.c:1350 [inline]
__se_sys_openat fs/open.c:1345 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1345
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1c5aea7407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fffc960cd90 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f1c5b5b8880 RCX: 00007f1c5aea7407
RDX: 0000000000080000 RSI: 00007fffc960cf10 RDI: ffffffffffffff9c
RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000561c1be147f5
R13: 0000561c1be147f5 R14: 0000000000000001 R15: 00007fffc9611560
</TASK>
rcu: rcu_preempt kthread starved for 10430 jiffies! g126581 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:27200 pid:16 ppid:2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 26529 Comm: kworker/0:14 Not tainted 6.1.148-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events pcpu_balance_workfn
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0xe7b/0x1270 kernel/smp.c:998
Code: 00 00 00 41 8b 1f 89 de 83 e6 01 31 ff e8 5d d9 0a 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 e9 d5 0a 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 ce d5 0a
RSP: 0018:ffffc9000533fa20 EFLAGS: 00000293
RAX: ffffffff8175e892 RBX: dffffc0000000000 RCX: ffff88802ef03b80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000533fb68 R08: dffffc0000000000 R09: fffffbfff215bc49
R10: fffffbfff215bc49 R11: 1ffffffff215bc48 R12: 1ffff110171e81c1
R13: ffff8880b8e3bb40 R14: 0000000000000001 R15: ffff8880b8f40e08
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33214000 CR3: 000000005d9b9000 CR4: 00000000003506f0
DR0: 000000000000a7d0 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
pcpu_post_unmap_tlb_flush mm/percpu-vm.c:188 [inline]
pcpu_reclaim_populated mm/percpu.c:2209 [inline]
pcpu_balance_workfn+0x657/0x10b0 mm/percpu.c:2245
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
vkms_vblank_simulate: vblank timer overrun