rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7573/1:b..l
(detected by 1, t=10502 jiffies, g=30893, q=6 ncpus=2)
task:syz.2.834 state:R running task stack:25248 pid:7573 ppid:4275 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:2891 [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: 0033:0x7f1df638eec9
RSP: 002b:00007f1df72f9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f1df65e5fa0 RCX: 00007f1df638eec9
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f1df6411f91 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1df65e6038 R14: 00007f1df65e5fa0 R15: 00007ffd9e19ed98
rcu: rcu_preempt kthread starved for 9477 jiffies! g30893 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: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:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742
Code: 48 89 df e8 87 71 af f7 e9 4c ff ff ff e8 ad 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 37 13 65 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffc90000177de8 EFLAGS: 000002c6
RAX: 145d70dd376ef800 RBX: ffffffff8a218f77 RCX: 145d70dd376ef800
RDX: 0000000000000001 RSI: ffffffff8a8c0500 RDI: ffffffff8adefd20
RBP: ffffc90000177f20 R08: dffffc0000000000 R09: ffffed10171e6afa
R10: ffffed10171e6afa R11: 1ffff110171e6af9 R12: 0000000000000001
R13: dffffc0000000000 R14: ffff888017739dc0 R15: 1ffffffff1c3ecf6
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff4de49e40 CR3: 0000000020872000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
default_idle_call+0x84/0xc0 kernel/sched/idle.c:109
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1fc/0x570 kernel/sched/idle.c:303
cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401
start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281
secondary_startup_64_no_verify+0xcf/0xdb