rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5490/1:b..l P12158/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=53101, q=403 ncpus=2)
task:syz.4.1178 state:R running task stack:22816 pid:12158 tgid:12158 ppid:10321 task_flags:0x400640 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:unwind_next_frame+0x18e7/0x23d0 arch/x86/kernel/unwind_orc.c:679
Code: 24 48 01 c6 4c 89 f7 48 89 da e8 84 0d 00 00 84 c0 0f 84 47 01 00 00 48 bd 00 00 00 00 00 fc ff df 48 8b 44 24 20 0f b6 04 28 <84> c0 0f 85 17 08 00 00 b3 01 8b 84 24 8c 00 00 00 41 39 06 4c 8b
RSP: 0000:ffffc9000bb5df98 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffffff903ae4ee RCX: 0000000000000001
RDX: ffffc9000bb5e0a8 RSI: dffffc0000000000 RDI: ffffc9000bb5e190
RBP: dffffc0000000000 R08: ffffc9000bb5e190 R09: 0000000000000000
R10: ffffc9000bb5e0b8 R11: fffff5200176bc19 R12: ffffc9000bb5e0b8
R13: 1ffff9200176bc0f R14: ffffc9000bb5e068 R15: 1ffffffff2075c9e
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
__set_page_owner+0x8d/0x4c0 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x23d/0x2a0 mm/page_alloc.c:1887
prep_new_page mm/page_alloc.c:1895 [inline]
get_page_from_freelist+0x23a5/0x2440 mm/page_alloc.c:3955
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5264
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2505
shmem_alloc_folio mm/shmem.c:1902 [inline]
shmem_alloc_and_add_folio+0x423/0xf40 mm/shmem.c:1944
shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2539
shmem_get_folio mm/shmem.c:2645 [inline]
shmem_write_begin+0x16c/0x330 mm/shmem.c:3298
generic_perform_write+0x2c5/0x900 mm/filemap.c:4314
shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3473
__kernel_write_iter+0x428/0x910 fs/read_write.c:619
dump_emit_page fs/coredump.c:1298 [inline]
dump_user_range+0x8a0/0xc90 fs/coredump.c:1372
elf_core_dump+0x3369/0x3960 fs/binfmt_elf.c:2111
coredump_write+0x1121/0x18b0 fs/coredump.c:1049
do_coredump fs/coredump.c:1126 [inline]
vfs_coredump+0x3321/0x3e60 fs/coredump.c:1200
get_signal+0x1108/0x1340 kernel/signal.c:3019
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 kernel/entry/common.c:75 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x178/0x670 kernel/entry/common.c:196
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f93df78f751
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f93df9e6090 RCX: 00007f93df78f749
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007f93df813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f93df9e6128 R14: 00007f93df9e6090 R15: 00007ffe5a4bdc58
task:dhcpcd state:R running task stack:21240 pid:5490 tgid:5490 ppid:5489 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:422 [inline]
RIP: 0010:unwind_next_frame+0xe77/0x23d0 arch/x86/kernel/unwind_orc.c:600
Code: e8 ae 21 00 00 48 89 c3 48 bd 00 00 00 00 00 fc ff df 48 8b 44 24 30 80 3c 28 00 4c 8b 7c 24 10 74 08 4c 89 ff e8 c9 8b b3 00 <49> 89 1f 48 8b 44 24 58 80 3c 28 00 48 8b 5c 24 78 4c 8b 64 24 48
RSP: 0018:ffffc9000258f318 EFLAGS: 00000246
RAX: 1ffff920004b1e86 RBX: ffffffff8227642c RCX: 1ffff920004b1e01
RDX: ffffffff90442e00 RSI: 0000000000000002 RDI: ffffc9000258f760
RBP: dffffc0000000000 R08: 000000000000000a R09: ffffffff8e13efa0
R10: ffffc9000258f438 R11: ffffffff81acb2b0 R12: ffffc90002590000
R13: 1ffff920004b1e7f R14: ffffc9000258f3e8 R15: ffffc9000258f430
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:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4969 [inline]
slab_alloc_node mm/slub.c:5283 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5290
vm_area_dup+0x2b/0x680 mm/vma_init.c:123
dup_mmap+0x870/0x1b80 mm/mmap.c:1773
dup_mm kernel/fork.c:1529 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1581
copy_process+0x1812/0x3ba0 kernel/fork.c:2218
kernel_clone+0x21e/0x820 kernel/fork.c:2648
__do_sys_clone kernel/fork.c:2789 [inline]
__se_sys_clone kernel/fork.c:2773 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2773
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f30c12a9636
RSP: 002b:00007fffada28df0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fffada28df8 RCX: 00007f30c12a9636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007fffada49340 R08: 0000000000000000 R09: 0000000000000001
R10: 00007f30c11d5a10 R11: 0000000000000246 R12: 00007fffada28f30
R13: 0000000000000000 R14: 0000000000000000 R15: 000055a5a7ec1ac0
rcu: rcu_preempt kthread starved for 10551 jiffies! g53101 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:27640 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
__schedule_loop kernel/sched/core.c:6976 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6991
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x11b0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9b/0x2d0 kernel/rcu/tree.c:2297
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 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:
CPU: 1 UID: 0 PID: 12164 Comm: syz.9.1176 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:vcpu_enter_guest arch/x86/kvm/x86.c:11439 [inline]
RIP: 0010:vcpu_run+0x5215/0x7670 arch/x86/kvm/x86.c:11639
Code: 4c 8b a4 24 20 01 00 00 4c 89 e3 48 c1 eb 03 42 0f b6 04 3b 84 c0 0f 85 12 10 00 00 41 c6 04 24 01 e8 6f 9c 81 00 fb 4c 89 f0 <48> c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 d8 ae e0 00 49 ff 06
RSP: 0018:ffffc9000be0f5c0 EFLAGS: 00000202
RAX: ffff88807c3a6f88 RBX: 1ffff1100f874bd6 RCX: 0000000080000001
RDX: 0000000000000006 RSI: ffffffff8d9a0684 RDI: ffffffff8be08ae0
RBP: ffffc9000be0f9b0 R08: ffffffff8fa25b77 R09: 1ffffffff1f44b6e
R10: dffffc0000000000 R11: fffffbfff1f44b6f R12: ffff88807c3a5eb2
R13: ffff88807c3a5280 R14: ffff88807c3a6f88 R15: dffffc0000000000
FS: 00007f62c9b806c0(0000) GS:ffff888125d07000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000000b CR3: 00000000257b0000 CR4: 00000000003526f0
Call Trace:
kvm_arch_vcpu_ioctl_run+0x1148/0x1c90 arch/x86/kvm/x86.c:11984
kvm_vcpu_ioctl+0x99a/0xed0 virt/kvm/kvm_main.c:4492
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f62c8d8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f62c9b80038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f62c8fe6270 RCX: 00007f62c8d8f749
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006
RBP: 00007f62c8e13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f62c8fe6308 R14: 00007f62c8fe6270 R15: 00007fff91c48c78