rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7554/1:b..l
(detected by 1, t=10502 jiffies, g=38357, q=208 ncpus=2)
task:syz.0.835 state:R running task stack:25248 pid:7554 ppid:4266 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730
preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
filemap_map_pages+0xe27/0x10d0 mm/filemap.c:3499
do_fault_around mm/memory.c:4600 [inline]
do_read_fault mm/memory.c:4626 [inline]
do_fault mm/memory.c:4760 [inline]
handle_pte_fault mm/memory.c:5031 [inline]
__handle_mm_fault mm/memory.c:5173 [inline]
handle_mm_fault+0x2889/0x3e70 mm/memory.c:5294
faultin_page mm/gup.c:1026 [inline]
__get_user_pages+0x3ff/0xeb0 mm/gup.c:1250
populate_vma_page_range+0x214/0x2b0 mm/gup.c:1607
__mm_populate+0x248/0x370 mm/gup.c:1721
mm_populate include/linux/mm.h:2837 [inline]
vm_mmap_pgoff+0x203/0x2b0 mm/util.c:525
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3723d8ec29
RSP: 002b:00007f3724b39038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f3723fd5fa0 RCX: 00007f3723d8ec29
RDX: b635773f06ebbeef RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f3723e11e41 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3723fd6038 R14: 00007f3723fd5fa0 R15: 00007fffab34fef8
rcu: rcu_preempt kthread timer wakeup didn't happen for 10417 jiffies! g38357 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=29808
rcu: rcu_preempt kthread starved for 10418 jiffies! g38357 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26912 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7559 Comm: syz.1.836 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline]
RIP: 0010:rcu_is_watching+0x36/0xa0 kernel/rcu/tree.c:721
Code: e8 7f 69 ac 08 89 c3 83 f8 08 73 60 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 80 49 5e 8c 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 b0 e1 65 00 48 c7 c3 c8 57 03 00 49 03 1e 48 89
RSP: 0018:ffffc90000007fa8 EFLAGS: 00000046
RAX: 1ffffffff18bc930 RBX: 0000000000000000 RCX: f659b1099c53b300
RDX: 0000000000000000 RSI: ffffffff8adefc80 RDI: ffffffff8adefc40
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1c3eebe
R10: fffffbfff1c3eebe R11: 1ffffffff1c3eebd R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff8c5e4980 R15: dffffc0000000000
FS: 00007f06e0c606c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e420000 CR3: 000000007e641000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
trace_local_timer_exit arch/x86/include/asm/trace/irq_vectors.h:41 [inline]
__sysvec_apic_timer_interrupt+0x1aa/0x5a0 arch/x86/kernel/apic/apic.c:1125
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 ee f7 41 f7 48 89 df e8 46 bd 42 f7 e8 71 af 65 f7 fb bf 01 00 00 00 96 3a 36 f7 65 8b 05 97 f3 e0 75 85 c0 74 02 5b c3 e8 e4 04 df
RSP: 0018:ffffc90004f3fbb8 EFLAGS: 00000286
RAX: f659b1099c53b300 RBX: ffff888072ff3780 RCX: f659b1099c53b300
RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: 0000000000000001
RBP: ffff888072ff3c18 R08: dffffc0000000000 R09: ffffed100e5fe6f1
R10: ffffed100e5fe6f1 R11: 1ffff1100e5fe6f0 R12: 1ffff1100e5fe783
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
spin_unlock_irq include/linux/spinlock.h:401 [inline]
get_signal+0x1163/0x1350 kernel/signal.c:2874
arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f06dfd8ec27
Code: ff ff 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
RSP: 002b:00007f06e0c600e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f06dffd5fa8 RCX: 00007f06dfd8ec29
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f06dffd5fa8
RBP: 00007f06dffd5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f06dffd6038 R14: 00007ffc6d843450 R15: 00007ffc6d843538