rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=e794/1/0x4000000000000000 softirq=111784/111785 fqs=14
(detected by 1, t=10505 jiffies, g=192521, q=461 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 22877 Comm: syz.3.4843 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x80/0x290 mm/kasan/generic.c:189
Code: ff 4d 89 c1 49 c1 e9 03 4b 8d 1c 21 49 89 df 4d 29 df 49 83 ff 10 7f 29 4d 85 ff 0f 84 38 01 00 00 4c 89 cb 48 f7 d3 4c 01 f3 <41> 80 3b 00 0f 85 86 01 00 00 49 ff c3 48 ff c3 75 ee e9 18 01 00
RSP: 0018:ffffc90000007c70 EFLAGS: 00000086
RAX: 0000000000008001 RBX: ffffffffffffffff RCX: ffffffff886385a7
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88802895d2e0
RBP: ffff88802895d340 R08: ffff88802895d2e7 R09: 1ffff1100512ba5c
R10: dffffc0000000000 R11: ffffed100512ba5c R12: dffffc0000000001
R13: 0000000001f403e8 R14: 1ffff1100512ba5c R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f520ff8 CR3: 0000000050506000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
instrument_atomic_read include/linux/instrumented.h:72 [inline]
atomic64_read include/linux/atomic/atomic-instrumented.h:646 [inline]
taprio_set_budget net/sched/sch_taprio.c:551 [inline]
advance_sched+0x607/0x970 net/sched/sch_taprio.c:745
__run_hrtimer kernel/time/hrtimer.c:1747 [inline]
__hrtimer_run_queues+0x54a/0xd50 kernel/time/hrtimer.c:1811
hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873
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
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__kasan_check_read+0x6/0x10 mm/kasan/shadow.c:31
Code: 41 5f 5d c3 48 c7 c7 cb ed 60 8c eb 0a 48 c7 c7 4e 8b 45 8c 48 89 de e8 38 29 4f 08 31 ed eb d7 00 00 cc cc 89 f6 48 8b 0c 24 <31> d2 e9 a3 ec ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01 00 00 00 e9
RSP: 0018:ffffc9000d327478 EFLAGS: 00000286
RAX: ffffffff81c5a249 RBX: 0000000000000000 RCX: ffffffff81bf6807
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea0001c13100
RBP: ffffc9000d3275d0 R08: ffffffff8e1ffbef R09: 1ffffffff1c3ff7d
R10: dffffc0000000000 R11: fffffbfff1c3ff7e R12: 1ffffd4000382621
R13: ffffea0001c13100 R14: ffffea0001c13108 R15: 80000000704c4025
instrument_atomic_read include/linux/instrumented.h:72 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
PageCompound include/linux/page-flags.h:297 [inline]
page_mapcount include/linux/mm.h:884 [inline]
zap_pte_range mm/memory.c:1452 [inline]
zap_pmd_range mm/memory.c:1572 [inline]
zap_pud_range mm/memory.c:1601 [inline]
zap_p4d_range mm/memory.c:1622 [inline]
unmap_page_range+0x1157/0x2500 mm/memory.c:1643
unmap_vmas+0x260/0x390 mm/memory.c:1728
exit_mmap+0x20d/0x960 mm/mmap.c:3250
__mmput+0x118/0x3c0 kernel/fork.c:1205
exit_mm+0x25a/0x360 kernel/exit.c:566
do_exit+0x905/0x2480 kernel/exit.c:868
do_group_exit+0x217/0x2d0 kernel/exit.c:1023
get_signal+0x1272/0x1350 kernel/signal.c:2871
arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:316
exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1485
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f98c1252b27
Code: Unable to access opcode bytes at 0x7f98c1252afd.
RSP: 002b:00007f98c22d1120 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007f98c139ce59
RDX: 00007f98c22d1140 RSI: 00007f98c22d1270 RDI: 000000000000000b
RBP: 00007f98c1432d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007f98c1616038 R14: 00007f98c1615fa0 R15: 00007fff569da638
rcu: rcu_preempt kthread timer wakeup didn't happen for 10260 jiffies! g192521 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=105464
rcu: rcu_preempt kthread starved for 10261 jiffies! g192521 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27736 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 22642 Comm: kworker/u4:14 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0xea2/0x1290 kernel/smp.c:998
Code: 00 00 00 41 8b 1f 89 de 83 e6 01 31 ff e8 f6 f6 0a 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 82 f3 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 67 f3 0a
RSP: 0018:ffffc90005e4f800 EFLAGS: 00000293
RAX: ffffffff81779349 RBX: dffffc0000000000 RCX: ffff888026c51dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90005e4f960 R08: ffffffff90afa247 R09: 1ffffffff215f448
R10: dffffc0000000000 R11: fffffbfff215f449 R12: 1ffff110171c8601
R13: ffff8880b8f3bbc0 R14: 0000000000000000 R15: ffff8880b8e43008
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f98c13ea540 CR3: 000000000c88e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000009 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1165
on_each_cpu include/linux/smp.h:71 [inline]
text_poke_sync arch/x86/kernel/alternative.c:1574 [inline]
text_poke_bp_batch+0x2b7/0x850 arch/x86/kernel/alternative.c:1774
text_poke_flush arch/x86/kernel/alternative.c:1965 [inline]
text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972
arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x11f/0x240 kernel/jump_label.c:207
static_key_enable+0x16/0x20 kernel/jump_label.c:220
toggle_allocation_gate+0xba/0x470 mm/kfence/core.c:821
process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295