rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4391/1:b..l
(detected by 1, t=10502 jiffies, g=7677, q=128)
task:syz.2.40 state:R running task stack:26592 pid: 4391 ppid: 4177 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6780
irqentry_exit+0x63/0x70 kernel/entry/common.c:432
asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681
RIP: 0010:xas_load lib/xarray.c:238 [inline]
RIP: 0010:xas_find+0x1ca/0xab0 lib/xarray.c:1249
Code: 8b 04 24 44 0f b6 20 49 89 de 49 c1 ee 03 43 0f b6 04 3e 84 c0 75 79 44 0f b6 3b 45 0f b6 e4 44 89 e7 44 89 fe e8 26 2a 77 fd <45> 38 fc 0f 87 12 01 00 00 48 8b 7c 24 28 48 89 de e8 30 8e ff ff
RSP: 0018:ffffc9000315f6e8 EFLAGS: 00000297
RAX: ffffffff8400985a RBX: ffff888060f5b440 RCX: ffff88802bf81dc0
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888060f5b442 R08: ffff88802bf81dc0 R09: 0000000000000002
R10: 0000000000000003 R11: 0000000000000002 R12: 0000000000000000
R13: 1ffff9200062bf06 R14: 1ffff1100c1eb688 R15: 0000000000000000
first_map_page mm/filemap.c:3288 [inline]
filemap_map_pages+0x203/0x1390 mm/filemap.c:3314
do_fault_around mm/memory.c:4243 [inline]
do_read_fault mm/memory.c:4258 [inline]
do_fault mm/memory.c:4392 [inline]
handle_pte_fault mm/memory.c:4650 [inline]
__handle_mm_fault mm/memory.c:4785 [inline]
handle_mm_fault+0x2580/0x43c0 mm/memory.c:4883
faultin_page mm/gup.c:976 [inline]
__get_user_pages+0x93e/0x11c0 mm/gup.c:1197
populate_vma_page_range+0x213/0x290 mm/gup.c:1529
__mm_populate+0x26f/0x3a0 mm/gup.c:1638
mm_populate include/linux/mm.h:2632 [inline]
vm_mmap_pgoff+0x203/0x2b0 mm/util.c:556
ksys_mmap_pgoff+0x140/0x780 mm/mmap.c:1623
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ff394099929
RSP: 002b:00007ff391f01038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007ff3942c0fa0 RCX: 00007ff394099929
RDX: b635773f06ebbeef RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007ff39411bb39 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff3942c0fa0 R15: 00007fff63333e88
rcu: rcu_preempt kthread starved for 10530 jiffies! g7677 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:28032 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
schedule+0x11b/0x1e0 kernel/sched/core.c:6459
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 4387 Comm: syz.4.38 Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592
check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
rcu_pending kernel/rcu/tree.c:3932 [inline]
rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619
update_process_times+0x193/0x200 kernel/time/timer.c:1818
tick_sched_handle kernel/time/tick-sched.c:254 [inline]
tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
__run_hrtimer kernel/time/hrtimer.c:1690 [inline]
__hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:212 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:156 [inline]
RIP: 0010:wrmsr arch/x86/include/asm/msr.h:263 [inline]
RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:208
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 9f 6c c8 02 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc9000311fcb0 EFLAGS: 00000246
RAX: 00000000000000f6 RBX: ffffffff8bbafa10 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed10172267a7
R10: ffffed10172267a7 R11: 1ffff110172267a6 R12: ffff8880b9133b01
R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000020
arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31
irq_work_queue+0x95/0x140 kernel/irq_work.c:75
bpf_send_signal_common+0x2b2/0x420 kernel/trace/bpf_trace.c:820
____bpf_send_signal kernel/trace/bpf_trace.c:829 [inline]
bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:827
bpf_prog_7ba5217f62dcd359+0x38/0x788
bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline]
__bpf_prog_run include/linux/filter.h:628 [inline]
bpf_prog_run include/linux/filter.h:635 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline]
bpf_trace_run2+0x15b/0x2d0 kernel/trace/bpf_trace.c:1915
__bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18
trace_sys_enter+0x65/0x80 include/trace/events/syscalls.h:18
syscall_trace_enter+0x115/0x180 kernel/entry/common.c:77
do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fe78647db19
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007fe784348a80 EFLAGS: 00000246 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007fe786708fa0 RCX: 00007fe78647db19
RDX: 00007fe784348a80 RSI: 00007fe784348bb0 RDI: 0000000000000011
RBP: 00007fe786563b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe786708fa0 R15: 00007ffdc8d76ec8