rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P21482/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=83625, q=250 ncpus=2)
task:syz.4.5353 state:R running task stack:25256 pid:21482 tgid:21481 ppid:20858 task_flags:0x40054c flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
zap_pte_range mm/memory.c:1756 [inline]
zap_pmd_range mm/memory.c:1818 [inline]
zap_pud_range mm/memory.c:1847 [inline]
zap_p4d_range mm/memory.c:1868 [inline]
unmap_page_range+0x3a79/0x4370 mm/memory.c:1889
unmap_single_vma mm/memory.c:1932 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:1976
exit_mmap+0x248/0xb50 mm/mmap.c:1280
__mmput+0x118/0x420 kernel/fork.c:1130
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fefe498ebe9
RSP: 002b:00007fefe58400e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007fefe4bb5fa8 RCX: 00007fefe498ebe9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fefe4bb5fac
RBP: 00007fefe4bb5fa0 R08: 7fffffffffffffff R09: 0000000000000000
R10: 00000000000000b0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fefe4bb6038 R14: 00007ffeec7638d0 R15: 00007ffeec7639b8
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g83625 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=44170
rcu: rcu_preempt kthread starved for 10502 jiffies! g83625 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27560 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 21486 Comm: syz.6.5354 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__asan_memset+0x24/0x50 mm/kasan/shadow.c:84
Code: 90 90 90 90 90 90 f3 0f 1e fa 55 41 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 7e e4 ff ff 84 c0 <74> 11 4c 89 f7 89 ee 48 89 da 5b 41 5e 5d e9 e9 84 56 09 31 c0 5b
RSP: 0018:ffffc90000007cd0 EFLAGS: 00000002
RAX: ffffffff8b758701 RBX: 0000000000000018 RCX: ffffffff8b758756
RDX: 0000000000000001 RSI: 0000000000000018 RDI: ffff888029762340
RBP: 0000000000000000 R08: ffff888029762357 R09: 1ffff110052ec46a
R10: dffffc0000000000 R11: ffffed10052ec46b R12: ffff888029762340
R13: dffffc0000000000 R14: ffff888029762340 R15: ffff888029762340
FS: 0000000000000000(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d921ff8 CR3: 000000000df36000 CR4: 0000000000350ef0
Call Trace:
rb_link_node include/linux/rbtree.h:63 [inline]
rb_add_cached include/linux/rbtree.h:182 [inline]
timerqueue_add+0x186/0x200 lib/timerqueue.c:40
__run_hrtimer kernel/time/hrtimer.c:1778 [inline]
__hrtimer_run_queues+0x656/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:folio_test_head include/linux/page-flags.h:-1 [inline]
RIP: 0010:folio_test_large include/linux/page-flags.h:864 [inline]
RIP: 0010:folio_mapcount include/linux/mm.h:1141 [inline]
RIP: 0010:zap_present_folio_ptes mm/memory.c:1525 [inline]
RIP: 0010:zap_present_ptes mm/memory.c:1581 [inline]
RIP: 0010:do_zap_pte_range mm/memory.c:1682 [inline]
RIP: 0010:zap_pte_range mm/memory.c:1726 [inline]
RIP: 0010:zap_pmd_range mm/memory.c:1818 [inline]
RIP: 0010:zap_pud_range mm/memory.c:1847 [inline]
RIP: 0010:zap_p4d_range mm/memory.c:1868 [inline]
RIP: 0010:unmap_page_range+0x1fd1/0x4370 mm/memory.c:1889
Code: 48 8b 1b 48 89 de 48 83 e6 01 31 ff e8 78 5d b6 ff 48 83 e3 01 0f 85 09 22 00 00 48 bb 00 00 00 00 00 fc ff df 44 89 74 24 30 <4d> 89 fe 4c 8b 7c 24 58 4c 89 ff be 08 00 00 00 e8 2a c4 19 00 48
RSP: 0018:ffffc900050375e0 EFLAGS: 00000246
RAX: ffffffff82095298 RBX: dffffc0000000000 RCX: ffff888058f6da00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90005037890 R08: ffffea00010f07f3 R09: 1ffffd400021e0fe
R10: dffffc0000000000 R11: fffff9400021e0ff R12: dffffc0000000000
R13: 00007f3f13137000 R14: 8000000043c1f000 R15: ffffc90005037aa0
unmap_single_vma mm/memory.c:1932 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:1976
exit_mmap+0x248/0xb50 mm/mmap.c:1280
__mmput+0x118/0x420 kernel/fork.c:1130
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
__do_sys_exit_group kernel/exit.c:1113 [inline]
__se_sys_exit_group kernel/exit.c:1111 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111
x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3f1418ebe9
Code: Unable to access opcode bytes at 0x7f3f1418ebbf.
RSP: 002b:00007ffcd3856198 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3f1418ebe9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffcd38561fc R08: 00000004d385628f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000002d4
R13: 00000000000927c0 R14: 000000000007c9f8 R15: 00007ffcd3856250