rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (2 ticks this GP) idle=04ac/1/0x4000000000000000 softirq=51359/51360 fqs=2
rcu: (detected by 1, t=10502 jiffies, g=61977, q=210 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 10850 Comm: syz.0.1340 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:check_preemption_disabled+0x0/0xe0 lib/smp_processor_id.c:13
Code: c0 75 0f 65 8b 05 4c ba 80 08 85 c0 74 04 90 0f 0b 90 e9 53 fc ff ff 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <41> 54 55 53 48 83 ec 08 65 8b 1d 25 76 80 08 65 f7 05 16 76 80 08
RSP: 0018:ffffc90000007e20 EFLAGS: 00000087
RAX: 0000000000000000 RBX: ffff8880b84284d8 RCX: ffffffff81f45a24
RDX: 0000000000000000 RSI: ffffffff8e0006af RDI: ffffffff8c1c4400
RBP: ffffffff81f45f93 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff888032412540
R13: 0000000000000001 R14: 0000000000000087 R15: ffff8880b8428650
FS: 00007f4e3676e6c0(0000) GS:ffff888124383000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4e3676dff8 CR3: 000000003ecf1000 CR4: 00000000003526f0
Call Trace:
lockdep_recursion_inc kernel/locking/lockdep.c:465 [inline]
lock_release kernel/locking/lockdep.c:5888 [inline]
lock_release+0x9a/0x310 kernel/locking/lockdep.c:5875
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:176 [inline]
_raw_spin_unlock_irqrestore+0x1a/0x80 kernel/locking/spinlock.c:198
__run_hrtimer kernel/time/hrtimer.c:1926 [inline]
__hrtimer_run_queues+0x383/0xa00 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_lock_irqsave+0x0/0x60 kernel/locking/spinlock.c:165
Code: 48 89 df 58 5b e9 70 8c 58 f6 e8 bb a6 84 f6 eb c9 66 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 55 53 48 89 fb 9c 5d fa f7 c5 00 02 00 00 75 39 bf 01
RSP: 0018:ffffc90003ef7c98 EFLAGS: 00000287
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff81f493f8
RDX: 1ffffffff1c38324 RSI: ffffffff81f49406 RDI: ffff8880b84284c0
RBP: ffff8880b84284c0 R08: 0000000000000005 R09: 0000000000000007
R10: 0000000000000000 R11: 0000000000000000 R12: fffffbfff21ae18a
R13: ffff8880b8428508 R14: 000000000d19b81c R15: 0000000000000000
class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:571 [inline]
clock_was_set+0x173/0x870 kernel/time/hrtimer.c:994
do_settimeofday64+0x330/0x4d0 kernel/time/timekeeping.c:1603
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+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4e3599ce59
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:00007f4e3676e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 00007f4e35c16090 RCX: 00007f4e3599ce59
RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000000
RBP: 00007f4e35a32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4e35c16128 R14: 00007f4e35c16090 R15: 00007ffc6e3db8c8
rcu: rcu_preempt kthread starved for 10498 jiffies! g61977 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:26488 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1295/0x67a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
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: 1 UID: 0 PID: 5625 Comm: udevd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data+0x0/0x90 kernel/kcov.c:246
Code: ee 46 01 12 48 8b 80 e0 16 00 00 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <65> 8b 05 d9 46 01 12 49 89 f8 49 89 f1 49 89 d2 65 48 8b 3d b0 46
RSP: 0018:ffffc9000374f610 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81fc0c4d
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000005
RBP: ffff8880b8443360 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed101708866d R14: 0000000000000001 R15: ffff8880b853c600
FS: 00007f480679e880(0000) GS:ffff888124483000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4805e58d74 CR3: 00000000731f0000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
csd_lock_wait kernel/smp.c:342 [inline]
smp_call_function_many_cond+0x5ad/0x1700 kernel/smp.c:892
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
dup_mmap+0x1307/0x21b0 mm/mmap.c:1905
dup_mm kernel/fork.c:1534 [inline]
copy_mm kernel/fork.c:1586 [inline]
copy_process+0x6c78/0x7ed0 kernel/fork.c:2264
kernel_clone+0x176/0x9e0 kernel/fork.c:2722
__do_sys_clone+0xd9/0x120 kernel/fork.c:2863
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f48060f1636
Code: 89 df e8 6d e8 f6 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffcde616870 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffcde616878 RCX: 00007f48060f1636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 000055b88e76b8d0 R08: 0000000000000000 R09: 000055b886b66140
R10: 00007f480679eb50 R11: 0000000000000246 R12: 000055b88e784bc0
R13: 0000000000000000 R14: 0000000000000000 R15: 000055b886b4b4be