rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P13866/1:b..l P13880/1:b..l P13829/1:b..l P13884/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=66413, q=1913 ncpus=2)
task:modprobe state:R running task stack:24312 pid:13884 tgid:13884 ppid:6952 task_flags:0x40000c flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7047
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7071
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:1884 [inline]
zap_pmd_range mm/memory.c:1946 [inline]
zap_pud_range mm/memory.c:1975 [inline]
zap_p4d_range mm/memory.c:1996 [inline]
unmap_page_range+0x38bc/0x4170 mm/memory.c:2017
unmap_single_vma mm/memory.c:2059 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:2101
exit_mmap+0x239/0xb10 mm/mmap.c:1277
__mmput+0x118/0x430 kernel/fork.c:1173
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x658/0x2310 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
__do_sys_exit_group kernel/exit.c:1123 [inline]
__se_sys_exit_group kernel/exit.c:1121 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1121
x64_sys_call+0x2210/0x2210 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbd18b236c5
RSP: 002b:00007fff1ee4e448 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fbd18c24fe8 RCX: 00007fbd18b236c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000001
RBP: 0000000000000001 R08: 00007fff1ee4e3d8 R09: 0000000000000000
R10: 00007fff1ee4e270 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fbd18c23680 R15: 00007fbd18c25000
task:syz.9.1975 state:R running task stack:25616 pid:13829 tgid:13829 ppid:11439 task_flags:0x40044c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_notrace+0xd1/0x110 kernel/sched/core.c:7140
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:752
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x4b/0x3b0 kernel/locking/lockdep.c:5879
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
free_unref_folios+0xdb3/0x14f0 mm/page_alloc.c:3000
folios_put_refs+0x584/0x670 mm/swap.c:1002
free_pages_and_swap_cache+0x277/0x520 mm/swap_state.c:355
__tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404
zap_pte_range mm/memory.c:1893 [inline]
zap_pmd_range mm/memory.c:1946 [inline]
zap_pud_range mm/memory.c:1975 [inline]
zap_p4d_range mm/memory.c:1996 [inline]
unmap_page_range+0x3962/0x4170 mm/memory.c:2017
unmap_single_vma mm/memory.c:2059 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:2101
exit_mmap+0x239/0xb10 mm/mmap.c:1277
__mmput+0x118/0x430 kernel/fork.c:1173
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x658/0x2310 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0877a4d6e0
RSP: 002b:00007ffd1df904b8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00000000000c4a29 RCX: 00007f0877b8f749
RDX: 00007ffd1df904c0 RSI: 00007ffd1df905f0 RDI: 0000000000000011
RBP: 0000000000000032 R08: 3fffffffffffffff R09: 0000000c1df90d3f
R10: 00007ffd1df90b40 R11: 0000000000000246 R12: 00007f0877de5fac
R13: 00007ffd1df90b40 R14: 00000000000c4a5b R15: 00007ffd1df90b60
task:modprobe state:R running task stack:24312 pid:13880 tgid:13880 ppid:9163 task_flags:0x400000 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x20/0x3b0 kernel/locking/lockdep.c:5876
Code: 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 30 49 89 f5 49 89 fe 65 48 8b 05 60 ba df 10 <48> 89 44 24 28 0f 1f 44 00 00 65 8b 05 63 ba df 10 83 f8 08 0f 83
RSP: 0018:ffffc90004e8f230 EFLAGS: 00000286
RAX: a1772587fb1bd100 RBX: ffffffff90212201 RCX: a1772587fb1bd100
RDX: ffffc90004e8f301 RSI: ffffffff81743f85 RDI: ffffffff8df419e0
RBP: dffffc0000000000 R08: ffffc90004e8f7f0 R09: ffffc90004e8f3b8
R10: dffffc0000000000 R11: fffff520009d1e79 R12: ffffc90004e8f800
R13: ffffffff81743f85 R14: ffffffff8df419e0 R15: ffffffff81743f85
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
unpoison_slab_object mm/kasan/common.c:339 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5270
anon_vma_chain_alloc mm/rmap.c:141 [inline]
anon_vma_clone+0xb8/0x4f0 mm/rmap.c:287
__split_vma+0x351/0xa00 mm/vma.c:528
split_vma mm/vma.c:591 [inline]
vma_modify+0x952/0x1a70 mm/vma.c:1634
vma_modify_flags+0x208/0x2e0 mm/vma.c:1654
mprotect_fixup+0x43c/0xa30 mm/mprotect.c:756
do_mprotect_pkey+0x8c5/0xcd0 mm/mprotect.c:930
__do_sys_mprotect mm/mprotect.c:951 [inline]
__se_sys_mprotect mm/mprotect.c:948 [inline]
__x64_sys_mprotect+0x80/0x90 mm/mprotect.c:948
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc89cc0b2c7
RSP: 002b:00007ffe75eaf5d8 EFLAGS: 00000206 ORIG_RAX: 000000000000000a
RAX: ffffffffffffffda RBX: 00007fc89c8e26b0 RCX: 00007fc89cc0b2c7
RDX: 0000000000000001 RSI: 0000000000001000 RDI: 00007fc89c8d6000
RBP: 00007ffe75eaf8a0 R08: 0000000000000000 R09: 00007fc89c9752e0
R10: 00007fc89c8e26b0 R11: 0000000000000206 R12: 0000000000000038
R13: 000001ce738e39af R14: 0000000000000000 R15: 00007fc89cc1f310
task:vhost-13865 state:R running task stack:27536 pid:13866 tgid:13864 ppid:13227 task_flags:0x404040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: 8b 3d 64 65 d9 0b 48 89 de 5b e9 63 31 5b 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 08 60 7e 92 65 8b 15 68 af bc 10 81 e2 00 01 ff 00
RSP: 0018:ffffc90003337418 EFLAGS: 00000202
RAX: ffffffff8b5410a9 RBX: ffffc90003337580 RCX: d4b7011331891600
RDX: ffff88802d3a9e80 RSI: ffffffff8bc07bc0 RDI: ffffffff8bc07b80
RBP: ffffc90003337550 R08: ffff88802d3a9e80 R09: 0000000000000002
R10: 0000000000000406 R11: 0000000000000002 R12: ffffc90003337480
R13: 1ffff92000666e8c R14: 0000000000000001 R15: ffff888077ffc140
rcu_read_unlock include/linux/rcupdate.h:895 [inline]
mt_find+0x389/0x5e0 lib/maple_tree.c:6516
find_vma+0xe7/0x160 mm/mmap.c:906
lock_mm_and_find_vma+0x5f/0x300 mm/mmap_lock.c:453
do_user_addr_fault+0x331/0x1380 arch/x86/mm/fault.c:1359
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0010:copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
RIP: 0010:raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline]
RIP: 0010:__copy_from_user include/linux/uaccess.h:120 [inline]
RIP: 0010:vhost_copy_from_user drivers/vhost/vhost.c:1366 [inline]
RIP: 0010:vhost_get_desc drivers/vhost/vhost.c:1586 [inline]
RIP: 0010:vhost_get_vq_desc_n+0x6c7/0x2980 drivers/vhost/vhost.c:2883
Code: e8 ee d0 69 f9 e8 59 8a 07 fc 84 c0 0f 85 40 11 00 00 e8 9c 75 03 f9 0f 01 cb b9 10 00 00 00 48 8b b4 24 90 00 00 00 4c 89 f7 a4 0f 1f 00 49 89 cc 0f 01 ca e9 c3 04 00 00 e8 74 75 03 f9 ba
RSP: 0018:ffffc900033377e0 EFLAGS: 00050287
RAX: ffffffff88be3b14 RBX: ffff888063f591e0 RCX: 0000000000000010
RDX: ffffc9001cb71000 RSI: 0000000000000000 RDI: ffffc90003337a00
RBP: ffffc90003337a80 R08: ffffc90003337a0f R09: 1ffff92000666f41
R10: dffffc0000000000 R11: fffff52000666f42 R12: 0000000000000001
R13: ffff888063f54c00 R14: ffffc90003337a00 R15: dffffc0000000000
vhost_get_vq_desc+0x40/0x60 drivers/vhost/vhost.c:2966
vhost_vsock_handle_tx_kick+0x276/0xfe0 drivers/vhost/vsock.c:512
vhost_run_work_list+0x14e/0x1e0 drivers/vhost/vhost.c:454
vhost_task_fn+0x27c/0x430 kernel/vhost_task.c:49
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: rcu_preempt kthread starved for 10624 jiffies! g66413 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:27272 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
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+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
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: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: be f3 b4 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d f3 00 0d 00 f3 0f 1e fa fb f4 93 f3 b4 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8dc07d80 EFLAGS: 000002c6
RAX: 4d428f647734a800 RBX: ffffffff81978eba RCX: 4d428f647734a800
RDX: 0000000000000001 RSI: ffffffff8d790585 RDI: ffffffff8bc07be0
RBP: ffffffff8dc07ea8 R08: ffff8880b86336db R09: 1ffff110170c66db
R10: dffffc0000000000 R11: ffffed10170c66dc R12: ffffffff8f81fb70
R13: 1ffffffff1b92a68 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125e3a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0d6562f85e CR3: 0000000075b93000 CR4: 0000000000350ef0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1ea/0x520 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
rest_init+0x2de/0x300 init/main.c:757
start_kernel+0x3a7/0x400 init/main.c:1206
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147