rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (0 ticks this GP) idle=fdfc/1/0x4000000000000000 softirq=21622/21622 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7043
rcu: (detected by 1, t=10502 jiffies, g=21765, q=807 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7043 Comm: syz.3.433 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:match_held_lock+0x4/0x120 kernel/locking/lockdep.c:5356
Code: 3a 90 31 db 48 89 d8 5b 41 5e 41 5f c3 cc cc cc cc cc 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 <53> bb 01 00 00 00 48 39 77 10 0f 84 c6 00 00 00 0f b7 47 22 a9 e0
RSP: 0018:ffffc90000007ca8 EFLAGS: 00000083
RAX: 0000000000000005 RBX: ffff888033cfab18 RCX: 8000000001000002
RDX: ffff888033cf9f40 RSI: ffff8880799132c0 RDI: ffff888033cfab18
RBP: 00000000ffffffff R08: 0000000001000001 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f90 R12: 0000000000000046
R13: ffff888033cf9f40 R14: ffff8880799132c0 R15: 0000000000000001
FS: 00007f368c5f66c0(0000) GS:ffff8881233fb000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa19158a980 CR3: 000000007a576000 CR4: 00000000003526f0
Call Trace:
__lock_is_held kernel/locking/lockdep.c:5654 [inline]
lock_is_held_type+0x89/0x150 kernel/locking/lockdep.c:6016
lock_is_held include/linux/lockdep.h:249 [inline]
advance_sched+0x163/0xc80 net/sched/sch_taprio.c:942
__run_hrtimer kernel/time/hrtimer.c:2079 [inline]
__hrtimer_run_queues+0x3bc/0xa10 kernel/time/hrtimer.c:2136
hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2255
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:finish_task_switch+0x413/0xc60 kernel/sched/core.c:5434
Code: 04 00 00 41 c7 84 24 20 0e 00 00 00 00 00 00 0f 1f 44 00 00 49 83 c4 48 4c 89 e7 e8 47 31 74 0a e8 32 8d 3a 00 fb 4c 8b 65 c8 <49> 8d bc 24 18 17 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0
RSP: 0018:ffffc900033972c0 EFLAGS: 00000202
RAX: 0000000000004149 RBX: ffff8880b823d3a0 RCX: 8000000000000001
RDX: 0000000000000007 RSI: ffffffff8e6ada39 RDI: ffffffff8c8eab80
RBP: ffffc90003397310 R08: ffffffff91be31bf R09: 1ffffffff237c637
R10: dffffc0000000000 R11: fffffbfff237c638 R12: ffff888033cf9f40
R13: ffff8880b823d368 R14: dffffc0000000000 R15: 1ffff11017047a74
context_switch kernel/sched/core.c:5586 [inline]
__schedule+0x17e5/0x5830 kernel/sched/core.c:7382
preempt_schedule_common+0x7f/0xd0 kernel/sched/core.c:7561
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:201 [inline]
_raw_spin_unlock+0x41/0x50 kernel/locking/spinlock.c:213
spin_unlock include/linux/spinlock.h:401 [inline]
filemap_map_pages+0x1aba/0x2170 mm/filemap.c:4015
do_fault_around mm/memory.c:6070 [inline]
do_read_fault mm/memory.c:6103 [inline]
do_fault mm/memory.c:6246 [inline]
do_pte_missing+0x2067/0x3570 mm/memory.c:4778
handle_pte_fault mm/memory.c:6665 [inline]
__handle_mm_fault mm/memory.c:6817 [inline]
handle_mm_fault+0x1807/0x2f80 mm/memory.c:6984
faultin_page mm/gup.c:1130 [inline]
__get_user_pages+0x102b/0x1ea0 mm/gup.c:1432
populate_vma_page_range+0x311/0x3f0 mm/gup.c:1868
__mm_populate+0x25f/0x390 mm/gup.c:1971
mm_populate include/linux/mm.h:4454 [inline]
vm_mmap_pgoff+0x36e/0x520 mm/util.c:586
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: 0033:0x7f368e39fb19
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:00007f368c5f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f368e625fa0 RCX: 00007f368e39fb19
RDX: b635773f06ebbeea RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f368e437b70 R08: ffffffffffffffff R09: 0000000028f43000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f368e626038 R14: 00007f368e625fa0 R15: 00007ffe847d7df8
task:syz.3.433 state:R running task stack:24296 pid:7043 tgid:7040 ppid:5634 task_flags:0x400040 flags:0x00080010
Call Trace:
rcu: rcu_preempt kthread starved for 10502 jiffies! g21765 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:28152 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5830 kernel/sched/core.c:7382
__schedule_loop kernel/sched/core.c:7459 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7474
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x1230 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9c/0x340 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: 1 UID: 0 PID: 7044 Comm: syz.0.435 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:389 [inline]
RIP: 0010:csd_lock kernel/smp.c:422 [inline]
RIP: 0010:smp_call_function_many_cond+0x61e/0x1500 kernel/smp.c:970
Code: b6 04 04 84 c0 0f 85 d5 03 00 00 44 8b 3b 44 89 fe 83 e6 01 31 ff e8 e1 79 0c 00 41 83 e7 01 75 07 e8 c6 74 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: 0018:ffffc90003427320 EFLAGS: 00000293
RAX: ffffffff81bcae0e RBX: ffff8880b8244328 RCX: ffff888079abddc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003427470 R08: ffff888079abf35f R09: 1ffff1100f357e6b
R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff11017048865
R13: 0000000000000000 R14: ffff8880b8244320 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8881234fb000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c385288 CR3: 000000005947a000 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
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:460 [inline]
tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:403
tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:529
free_ldt_pgtables+0x192/0x360 arch/x86/kernel/ldt.c:411
arch_exit_mmap arch/x86/include/asm/mmu_context.h:229 [inline]
exit_mmap+0x1b7/0xa40 mm/mmap.c:1300
__mmput+0x118/0x420 kernel/fork.c:1192
exit_mm+0x18e/0x240 kernel/exit.c:586
do_exit+0x6a8/0x2360 kernel/exit.c:967
do_group_exit+0x22d/0x2f0 kernel/exit.c:1123
get_signal+0x136a/0x1430 kernel/signal.c:3113
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x10e/0x770 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+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1a5119fb19
Code: Unable to access opcode bytes at 0x7f1a5119faef.
RSP: 002b:00007f1a51fe70e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f1a51426098 RCX: 00007f1a5119fb19
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f1a51426098
RBP: 00007f1a51426090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a51426128 R14: 00007ffc72743800 R15: 00007ffc727438e8