rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=e26c/1/0x4000000000000000 softirq=91562/91563 fqs=11
rcu: (detected by 0, t=10502 jiffies, g=70777, q=491 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 17000 Comm: syz.1.4823 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026
RIP: 0010:__kasan_check_write+0x8/0x20 mm/kasan/shadow.c:37
Code: f3 ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 <89> f6 ba 01 00 00 00 e9 dc f2 ff ff 66 66 2e 0f 1f 84 00 00 00 00
RSP: 0018:ffffc90000a18df0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffff8880b8528500 RCX: ffffffff81e7ab38
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000a18e20
RBP: ffff8880b8528508 R08: 0000000000000001 R09: ffffed10170a50a0
R10: ffff8880b8528503 R11: 0000000000000000 R12: 1ffff920001431c0
R13: ffff8880b8528510 R14: ffff8880b8528740 R15: ffff8880b8528790
FS: 0000000000000000(0000) GS:ffff888123c53000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c45dfd3 CR3: 0000000032719000 CR4: 00000000003526f0
Call Trace:
instrument_read_write include/linux/instrumented.h:55 [inline]
atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1301 [inline]
queued_spin_lock include/asm-generic/qspinlock.h:112 [inline]
do_raw_spin_lock+0x128/0x260 kernel/locking/spinlock_debug.c:116
__run_hrtimer kernel/time/hrtimer.c:2078 [inline]
__hrtimer_run_queues+0x1b7/0x9c0 kernel/time/hrtimer.c:2131
hrtimer_interrupt+0x441/0xaa0 kernel/time/hrtimer.c:2250
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:write_comp_data+0x90/0xa0 kernel/kcov.c:268
Code: 00 00 4a 8d 14 dd 28 00 00 00 48 39 d7 72 1b 48 83 c6 01 48 89 30 4c 89 44 10 e0 4c 89 4c 10 e8 4c 89 54 10 f0 4a 89 4c d8 20 5b ab c8 09 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90
RSP: 0018:ffffc9000490f528 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff82628ea8
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff88804a164b00
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 000000110c2ac000
R13: 8000000073374025 R14: dffffc0000000000 R15: ffffea0001ccdd18
zap_present_folio_ptes mm/memory.c:1780 [inline]
zap_present_ptes mm/memory.c:1861 [inline]
do_zap_pte_range mm/memory.c:1963 [inline]
zap_pte_range mm/memory.c:2065 [inline]
zap_pmd_range mm/memory.c:2151 [inline]
zap_pud_range mm/memory.c:2179 [inline]
zap_p4d_range mm/memory.c:2200 [inline]
__zap_vma_range+0x1218/0x48e0 mm/memory.c:2240
unmap_vmas+0x299/0x5f0 mm/memory.c:2309
exit_mmap+0x1ef/0xa00 mm/mmap.c:1315
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:618 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:1000
do_group_exit+0xd5/0x2a0 kernel/exit.c:1155
get_signal+0x1ec7/0x21e0 kernel/signal.c:3112
arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x139/0x700 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
do_syscall_64+0x661/0x790 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f894139e159
Code: Unable to access opcode bytes at 0x7f894139e12f.
RSP: 002b:00007f89421970e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f8941625fa8 RCX: 00007f894139e159
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f8941625fa8
RBP: 00007f8941625fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8941626038 R14: 00007ffe8b6f4b80 R15: 00007ffe8b6f4c68
rcu: rcu_preempt kthread starved for 10477 jiffies! g70777 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27560 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x1259/0x6920 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7376
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x8f0 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x17a/0x220 kernel/rcu/tree.c:2330
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 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: 16986 Comm: syz.3.4817 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026
RIP: 0010:csd_lock_wait kernel/smp.c:363 [inline]
RIP: 0010:csd_lock kernel/smp.c:396 [inline]
RIP: 0010:smp_call_function_many_cond+0x59b/0x18c0 kernel/smp.c:944
Code: 0b c5 0c 00 f3 90 41 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 51 11 00 00 44 8b 73 08 31 ff 41 83 e6 01 44 89 f6 e8 55 bf 0c 00 <45> 85 f6 75 d0 e8 db c4 0c 00 e8 d6 c4 0c 00 48 89 ea 48 b8 00 00
RSP: 0018:ffffc900035df5f8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b8541900 RCX: ffffffff81ff5dab
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff888035722580
RBP: ffff8880b8541908 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000003
R13: ffffed10170a8321 R14: 0000000000000001 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888123b53000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d611ff8 CR3: 00000000450c2000 CR4: 00000000003526f0
DR0: 0000000000010000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
__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+0x3c9/0x1360 arch/x86/mm/tlb.c:1435
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+0x454/0xa00 mm/mmap.c:1328
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:618 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:1000
do_group_exit+0xd5/0x2a0 kernel/exit.c:1155
get_signal+0x1ec7/0x21e0 kernel/signal.c:3112
arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x139/0x700 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
do_syscall_64+0x661/0x790 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd1eb39e159
Code: Unable to access opcode bytes at 0x7fd1eb39e12f.
RSP: 002b:00007fd1ec1a70e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fd1eb625fa8 RCX: 00007fd1eb39e159
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fd1eb625fa8
RBP: 00007fd1eb625fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd1eb626038 R14: 00007fff77ef2750 R15: 00007fff77ef2838