rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10500 ticks this GP) idle=5c24/1/0x4000000000000000 softirq=41693/2209131 fqs=2
rcu: 	(t=10500 jiffies g=21741 q=216 ncpus=2)
rcu: rcu_preempt kthread starved for 10495 jiffies! g21741 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:27496 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6860
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2046
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2248
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9161 Comm: syz.0.970 Not tainted 6.15.0-rc4-syzkaller-gf4efc73b1ee7 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:81
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 03 1b 12 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000462f918 EFLAGS: 000002c7
RAX: ffffffff8170fcbd RBX: 0000000000000003 RCX: 0000000000080000
RDX: ffffc9000decc000 RSI: 0000000000066ce3 RDI: 0000000000066ce4
RBP: ffffc9000462f9f0 R08: ffffffff8f7ed277 R09: 1ffffffff1efda4e
R10: dffffc0000000000 R11: fffffbfff1efda4f R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000003 R15: 1ffff920008c5f28
FS:  00007fec6cf1a6c0(0000) GS:ffff8881260cc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fec6cf19f98 CR3: 00000000285dc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 kvm_wait+0x232/0x290 arch/x86/kernel/kvm.c:1063
 pv_wait arch/x86/include/asm/paravirt.h:584 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:466 [inline]
 __pv_queued_spin_lock_slowpath+0x7bf/0xb60 kernel/locking/qspinlock.c:325
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:572 [inline]
 queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x21f/0x290 kernel/locking/spinlock_debug.c:116
 spin_lock include/linux/spinlock.h:351 [inline]
 d_instantiate+0x64/0xa0 fs/dcache.c:1937
 alloc_path_pseudo fs/file_table.c:364 [inline]
 alloc_file_pseudo+0xf6/0x210 fs/file_table.c:376
 __anon_inode_getfile fs/anon_inodes.c:109 [inline]
 anon_inode_getfile+0xc5/0x1a0 fs/anon_inodes.c:147
 __do_sys_perf_event_open kernel/events/core.c:13350 [inline]
 __se_sys_perf_event_open+0xe6c/0x1c80 kernel/events/core.c:13061
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fec6c18e969
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:00007fec6cf1a038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fec6c3b6080 RCX: 00007fec6c18e969
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000480
RBP: 00007fec6c210ab1 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fec6c3b6080 R15: 00007ffe853bdf58
 </TASK>
CPU: 1 UID: 0 PID: 9144 Comm: syz.1.966 Not tainted 6.15.0-rc4-syzkaller-gf4efc73b1ee7 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:note_gp_changes+0x25f/0x300 kernel/rcu/tree.c:1332
Code: 1f 00 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 f6 44 24 41 02 75 4f 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 20 0e 36 e0 45 <4a> c7 04 2b 00 00 00 00 66 42 c7 44 2b 09 00 00 42 c6 44 2b 0b 00
RSP: 0018:ffffc90000a08b00 EFLAGS: 00000206
RAX: f0f00fff9083e900 RBX: 1ffff92000141164 RCX: f0f00fff9083e900
RDX: 0000000000000002 RSI: ffffffff8d74a66e RDI: ffffffff8bc1d020
RBP: ffffc90000a08bd0 R08: ffffffff8f7ed277 R09: 1ffffffff1efda4e
R10: dffffc0000000000 R11: fffffbfff1efda4f R12: ffff8880b893ab14
R13: dffffc0000000000 R14: 0000000000000a02 R15: ffff8880b893ab00
FS:  000055558d0fb500(0000) GS:ffff8881261cc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3040eff8 CR3: 0000000027986000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_check_quiescent_state kernel/rcu/tree.c:2452 [inline]
 rcu_core+0x29d/0x1710 kernel/rcu/tree.c:2808
 handle_softirqs+0x283/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0xa3/0xc0 arch/x86/kernel/irq_work.c:17
 </IRQ>
 <TASK>
 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738
RIP: 0010:rcu_read_unlock_special+0x87/0x4c0 kernel/rcu/tree_plugin.h:694
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 e2 a3 cd 10 41 f7 c6 00 00 f0 00 74 49 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc900048dfc20 EFLAGS: 00000206
RAX: f0f00fff9083e900 RBX: 1ffff9200091bf8c RCX: f0f00fff9083e900
RDX: 0000000000000006 RSI: ffffffff8d74a66e RDI: ffffffff8bc1d020
RBP: ffffc900048dfd10 R08: ffffffff8f7ed277 R09: 1ffffffff1efda4e
R10: dffffc0000000000 R11: fffffbfff1efda4f R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000246 R15: ffffffff8df40ca0
 __rcu_read_unlock+0x84/0xe0 kernel/rcu/tree_plugin.h:438
 dput+0x197/0x2b0 fs/dcache.c:901
 __fput+0x68e/0xa70 fs/file_table.c:473
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218
 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3af438e969
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:00007ffcd71d8848 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f3af45b7ba0 RCX: 00007f3af438e969
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f3af45b7ba0 R08: 000000000000eb44 R09: 00000017d71d8b3f
R10: 00000000005ee038 R11: 0000000000000246 R12: 000000000005751d
R13: 00007f3af45b6080 R14: ffffffffffffffff R15: 00007ffcd71d8960
 </TASK>