rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7095/1:b..l P7070/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=20633, q=486 ncpus=2)
task:syz.0.279 state:R running task stack:21816 pid:7070 tgid:7070 ppid:5835 task_flags:0x400640 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7113
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7137
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]
follow_page_pte+0xc71/0x13e0 mm/gup.c:889
follow_pmd_mask mm/gup.c:-1 [inline]
follow_pud_mask mm/gup.c:967 [inline]
follow_p4d_mask mm/gup.c:984 [inline]
follow_page_mask mm/gup.c:1023 [inline]
__get_user_pages+0xa6c/0x29f0 mm/gup.c:1426
__get_user_pages_locked mm/gup.c:1692 [inline]
get_dump_page+0x1ac/0x3f0 mm/gup.c:2192
dump_user_range+0x1de/0xc90 fs/coredump.c:1366
elf_core_dump+0x3369/0x3960 fs/binfmt_elf.c:2111
coredump_write+0x116c/0x1900 fs/coredump.c:1049
vfs_coredump+0x1db5/0x2a60 fs/coredump.c:1170
get_signal+0x1108/0x1340 kernel/signal.c:3019
arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:40 [inline]
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
irqentry_exit_to_user_mode+0x7e/0x110 kernel/entry/common.c:73
exc_page_fault+0xab/0x100 arch/x86/mm/fault.c:1535
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f99f978eed1
RSP: 002b:00000000fffffd10 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f99f99e5fa0 RCX: 00007f99f978eec9
RDX: 0000000000000000 RSI: 00000000fffffd10 RDI: 0000000001000000
RBP: 00007f99f9811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f99f99e6038 R14: 00007f99f99e5fa0 R15: 00007fff2b762968
task:dhcpcd-run-hook state:R running task stack:27112 pid:7095 tgid:7095 ppid:7049 task_flags:0x40004c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:127 [inline]
RIP: 0010:lock_release+0xa6/0x3e0 kernel/locking/lockdep.c:5885
Code: 25 08 00 92 92 41 83 bf 2c 0b 00 00 00 0f 85 1e 02 00 00 49 81 3e 40 b3 55 93 0f 84 11 02 00 00 48 c7 44 24 20 00 00 00 00 9c <8f> 44 24 20 48 8b 5c 24 20 fa 48 c7 c7 03 32 80 8d e8 04 e1 b0 09
RSP: 0018:ffffc900047b7488 EFLAGS: 00000206
RAX: 0000000000000000 RBX: ffffffff902d2801 RCX: 78748ce459e12300
RDX: ffffc900047b7601 RSI: ffffffff8bc07cc0 RDI: ffffffff8bc07c80
RBP: dffffc0000000000 R08: ffffc900047b7c50 R09: 0000000000000000
R10: ffffc900047b7618 R11: fffff520008f6ec5 R12: ffffc900047b7c60
R13: ffffffff8173cd25 R14: ffffffff8e13d2e0 R15: ffff8880262dbc80
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
poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417
kasan_kmalloc include/linux/kasan.h:262 [inline]
__kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5755
kmalloc_noprof include/linux/slab.h:957 [inline]
slab_free_hook mm/slub.c:2482 [inline]
slab_free mm/slub.c:6619 [inline]
kmem_cache_free+0x16f/0x690 mm/slub.c:6729
exit_mmap+0x537/0xb40 mm/mmap.c:1302
__mmput+0x118/0x430 kernel/fork.c:1133
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:954
do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
__do_sys_exit_group kernel/exit.c:1118 [inline]
__se_sys_exit_group kernel/exit.c:1116 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1116
x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9f1c9ce6c5
RSP: 002b:00007ffe24c33fc8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007ffe24c34204 RCX: 00007f9f1c9ce6c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000
RBP: 0000000000000003 R08: 00007ffe24c340c0 R09: 0000000000000002
R10: 00007f9f1ca74fe0 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffe24c34300 R14: 00007f9f1cbde000 R15: 000055d40c9ced98
rcu: rcu_preempt kthread starved for 10137 jiffies! g20633 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:27912 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
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+0x4bc/0x870 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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc 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 53 b1 19 00 f3 0f 1e fa fb f4 48 e7 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6
RAX: 176502b2bbccf600 RBX: ffffffff8196d367 RCX: 176502b2bbccf600
RDX: 0000000000000001 RSI: ffffffff8d7eeef8 RDI: ffffffff8bc07ce0
RBP: ffffc90000197f10 R08: ffff8880b8732fdb R09: 1ffff110170e65fb
R10: dffffc0000000000 R11: ffffed10170e65fc R12: ffffffff8f9e3170
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110039ddb58
FS: 0000000000000000(0000) GS:ffff888125e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe24c340b8 CR3: 0000000076ab6000 CR4: 00000000003526f0
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:190 [inline]
do_idle+0x1e7/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x147