rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=7094/1/0x4000000000000000 softirq=26782/26783 fqs=1
rcu: (detected by 0, t=10503 jiffies, g=26173, q=1509 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6570 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:__lock_acquire+0x2f1/0x2de0 kernel/locking/lockdep.c:-1
Code: 49 89 f7 4c 89 f6 e8 5e b7 7a 03 4c 89 fe 44 8b 3c 24 48 83 bc 24 20 01 00 00 00 0f 85 ad fe ff ff 44 89 3c 24 44 89 6c 24 40 <89> 6c 24 28 8b bc 24 48 01 00 00 8b ac 24 38 01 00 00 4c 8b 84 24
RSP: 0018:ffffc90000a18b00 EFLAGS: 00000046
RAX: 000000000000e439 RBX: 0000000000000000 RCX: ffffffff953ce4d0
RDX: 0000000000000000 RSI: 0000000000000921 RDI: ffffffff9befba40
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: dffffc0000000000 R11: ffffffff89efeea0 R12: 0000000000000000
R13: 0000000000000001 R14: 0000000000000003 R15: 0000000000000000
FS: 0000555560f0f500(0000) GS:ffff888123bbd000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f691d470ca8 CR3: 0000000070274000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
__raw_spin_lock include/linux/spinlock_api_smp.h:190 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:173
spin_lock include/linux/spinlock.h:347 [inline]
advance_sched+0xc2/0xc80 net/sched/sch_taprio.c:931
__run_hrtimer kernel/time/hrtimer.c:2074 [inline]
__hrtimer_run_queues+0x3bc/0xa10 kernel/time/hrtimer.c:2131
hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2250
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:check_kcov_mode kernel/kcov.c:190 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:242 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x52/0xa0 kernel/kcov.c:317
Code: 00 0f 41 81 f8 00 01 00 00 41 0f 95 c0 81 fa 00 00 00 10 0f 93 c2 44 08 c2 75 57 83 b9 44 17 00 00 00 74 4e 8b 91 18 17 00 00 <83> fa 03 75 43 48 8b 91 20 17 00 00 44 8b 89 1c 17 00 00 49 c1 e1
RSP: 0018:ffffc90003a9f730 EFLAGS: 00000246
RAX: ffffffff8244ee63 RBX: 0000000000000001 RCX: ffff888032220000
RDX: 0000000000000000 RSI: 000000000006c092 RDI: 0000000400000000
RBP: ffffc90003a9fad0 R08: ffff888075c07b17 R09: 1ffff1100eb80f62
R10: dffffc0000000000 R11: ffffed100eb80f63 R12: dffffc0000000000
R13: ffffea0001b02480 R14: 000000000006c092 R15: 8000000000000025
__nr_to_section include/linux/mmzone.h:2063 [inline]
__pfn_to_section include/linux/mmzone.h:2193 [inline]
pfn_valid+0x463/0x490 include/linux/mmzone.h:2275
page_table_check_clear+0x21/0x500 mm/page_table_check.c:70
page_table_check_pte_clear include/linux/page_table_check.h:55 [inline]
ptep_get_and_clear arch/x86/include/asm/pgtable.h:1243 [inline]
__ptep_modify_prot_start include/linux/pgtable.h:1595 [inline]
ptep_modify_prot_start include/linux/pgtable.h:1628 [inline]
modify_prot_start_ptes include/linux/pgtable.h:1674 [inline]
change_present_ptes mm/mprotect.c:291 [inline]
change_pte_range mm/mprotect.c:403 [inline]
change_pmd_range mm/mprotect.c:560 [inline]
change_pud_range mm/mprotect.c:623 [inline]
change_p4d_range mm/mprotect.c:649 [inline]
change_protection_range mm/mprotect.c:677 [inline]
change_protection+0x34cb/0x4e20 mm/mprotect.c:724
mprotect_fixup+0x704/0xad0 mm/mprotect.c:842
do_mprotect_pkey+0x8e7/0xd10 mm/mprotect.c:1002
__do_sys_mprotect mm/mprotect.c:1023 [inline]
__se_sys_mprotect mm/mprotect.c:1020 [inline]
__x64_sys_mprotect+0x80/0x90 mm/mprotect.c:1020
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f691d39df57
Code: 89 38 eb 84 0f 1f 80 00 00 00 00 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff e9 7a ff ff ff b8 0a 00 00 00 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:00007fff76cb0ef8 EFLAGS: 00000206 ORIG_RAX: 000000000000000a
RAX: ffffffffffffffda RBX: 00007f691d5f38a0 RCX: 00007f691d39df57
RDX: 0000000000000001 RSI: 0000000000130000 RDI: 00007f691d4bc000
RBP: 00007fff76cb0f98 R08: 0000555560f10850 R09: 0000555560f10870
R10: 0000000000000005 R11: 0000000000000206 R12: 00007fff76cb0fb0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 10497 jiffies! g26173 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:27496 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7376
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 6258 Comm: udevd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
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+0x61e/0x1500 kernel/smp.c:944
Code: b6 04 04 84 c0 0f 85 d5 03 00 00 44 8b 3b 44 89 fe 83 e6 01 31 ff e8 91 59 0c 00 41 83 e7 01 75 07 e8 86 54 0c 00 eb 3f f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 04 04 84 c0 75 0f f7 03 01
RSP: 0000:ffffc9000370f720 EFLAGS: 00000293
RAX: ffffffff81bbbc1e RBX: ffff8880b85414c8 RCX: ffff88801ef8ddc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000370f870 R08: ffff88801ef8f35f R09: 1ffff11003df1e6b
R10: dffffc0000000000 R11: ffffffff8179fad0 R12: 1ffff110170a8299
R13: 0000000000000001 R14: ffff8880b85414c0 R15: 0000000000000001
FS: 00007f3fa8f4f880(0000) GS:ffff888123abd000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564ff94dff28 CR3: 0000000073bf6000 CR4: 00000000003526f0
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+0x910/0x10b0 arch/x86/mm/tlb.c:1435
flush_tlb_page arch/x86/include/asm/tlbflush.h:352 [inline]
ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:104
wp_page_copy mm/memory.c:4073 [inline]
do_wp_page+0x3c5c/0x4b80 mm/memory.c:4472
handle_pte_fault mm/memory.c:6582 [inline]
__handle_mm_fault mm/memory.c:6707 [inline]
handle_mm_fault+0x15d7/0x3750 mm/memory.c:6876
do_user_addr_fault+0xa4f/0x1340 arch/x86/mm/fault.c:1343
handle_page_fault arch/x86/mm/fault.c:1483 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7f3fa8fe9b69
Code: 10 48 81 f9 ff 03 00 00 76 28 48 8b 57 20 48 85 d2 74 1f 48 3b 7a 28 75 76 48 8b 4f 28 48 3b 79 20 75 6c 48 83 78 20 00 74 17 <48> 89 4a 28 48 89 51 20 48 83 c4 08 c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffd24cb45d0 EFLAGS: 00010206
RAX: 00007f3fa9126220 RBX: 0000000000003030 RCX: 0000564ff94dff00
RDX: 0000564ff94dff00 RSI: 00007f3fa9126220 RDI: 0000564ff94dff00
RBP: 00007f3fa9125ac0 R08: 0000000000003030 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000564ff94dc2b0
R13: 00007f3fa9125ac0 R14: 0000000000003030 R15: 00007f3fa9125ac0