rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=37d4/1/0x4000000000000000 softirq=92285/92285 fqs=1
rcu: 	(detected by 0, t=10502 jiffies, g=82013, q=416 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 19193 Comm: syz-executor Not tainted 6.15.0-rc5-syzkaller-00022-g01f95500a162 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:__lock_acquire+0x6a/0xd20 kernel/locking/lockdep.c:5109
Code: 89 d2 8b 0d 58 a7 42 0c 85 c9 0f 44 e9 45 31 e4 48 3d e0 c6 35 93 41 0f 44 ec 83 fe 01 48 89 3c 24 77 0c 89 f0 48 8b 44 c3 08 <48> 85 c0 75 23 48 89 df 31 d2 45 89 ce 45 89 d5 e8 31 f0 ff ff 45
RSP: 0018:ffffc90000a08b50 EFLAGS: 00000097
RAX: ffffffff931acc58 RBX: ffffffff8df3b860 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888026d68000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: ffffed1004fd205e R12: 0000000000000000
R13: ffffffff8df3b860 R14: 0000000000000000 R15: 0000000000000002
FS:  000055557b598500(0000) GS:ffff8881261fd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555ba36588 CR3: 00000000679c8000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 advance_sched+0xa14/0xc90 net/sched/sch_taprio.c:985
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x18/0x70 kernel/kcov.c:217
Code: cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 30 72 92 65 8b 15 b8 60 b2 10 <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 3c 16 00 00
RSP: 0018:ffffc9000b7373d0 EFLAGS: 00000202
RAX: ffffffff822a78c6 RBX: 000000000006048c RCX: ffff888026d68000
RDX: 0000000080000002 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff822a915b R12: 0000000000000180
R13: 0000000000000000 R14: ffff88801b600000 R15: dffffc0000000000
 lookup_page_ext mm/page_ext.c:254 [inline]
 page_ext_lookup+0xf6/0x160 mm/page_ext.c:520
 page_ext_iter_begin include/linux/page_ext.h:132 [inline]
 page_table_check_set+0x23b/0x710 mm/page_table_check.c:113
 page_table_check_ptes_set include/linux/page_table_check.h:74 [inline]
 set_ptes include/linux/pgtable.h:292 [inline]
 __copy_present_ptes mm/memory.c:961 [inline]
 copy_present_ptes mm/memory.c:1044 [inline]
 copy_pte_range mm/memory.c:1167 [inline]
 copy_pmd_range+0x427d/0x7000 mm/memory.c:1255
 copy_pud_range mm/memory.c:1292 [inline]
 copy_p4d_range mm/memory.c:1316 [inline]
 copy_page_range+0x95c/0xd40 mm/memory.c:1410
 dup_mmap kernel/fork.c:726 [inline]
 dup_mm kernel/fork.c:1734 [inline]
 copy_mm+0x121c/0x2100 kernel/fork.c:1786
 copy_process+0x16d3/0x3b80 kernel/fork.c:2429
 kernel_clone+0x224/0x7f0 kernel/fork.c:2844
 __do_sys_clone kernel/fork.c:2987 [inline]
 __se_sys_clone kernel/fork.c:2971 [inline]
 __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2971
 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: 0033:0x7f34569851d3
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffecd0e9928 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f34569851d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055557b5987d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 0000000000070d8d R15: 00007ffecd0e9ac0
 </TASK>
rcu: rcu_preempt kthread starved for 10495 jiffies! g82013 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:27304 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x168f/0x4c70 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:
CPU: 0 UID: 0 PID: 19664 Comm: syz.1.6079 Not tainted 6.15.0-rc5-syzkaller-00022-g01f95500a162 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xe69/0x11c0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 10 6d 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 bb 68 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 a0 68 0b
RSP: 0018:ffffc9000435f700 EFLAGS: 00000293
RAX: ffffffff81b466c0 RBX: ffff8880b883abc0 RCX: ffff88802d218000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000435f860 R08: ffffffff8f7daf77 R09: 1ffffffff1efb5ee
R10: dffffc0000000000 R11: fffffbfff1efb5ef R12: 1ffff11017127e69
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b893f348
FS:  0000000000000000(0000) GS:ffff8881260fd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f81bff8 CR3: 000000007e4e8000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1275 [inline]
 flush_tlb_mm_range+0x6ae/0x12b0 arch/x86/mm/tlb.c:1365
 tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:480 [inline]
 tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403
 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:496
 exit_mmap+0x474/0xba0 mm/mmap.c:1297
 __mmput+0x118/0x410 kernel/fork.c:1379
 exit_mm+0x1da/0x2c0 kernel/exit.c:589
 do_exit+0x859/0x2550 kernel/exit.c:940
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
 __do_sys_exit_group kernel/exit.c:1113 [inline]
 __se_sys_exit_group kernel/exit.c:1111 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111
 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
 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: 0033:0x7f8c8718e969
Code: Unable to access opcode bytes at 0x7f8c8718e93f.
RSP: 002b:00007ffe35aed3f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8c8718e969
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe35aed45c R08: 0000000435aed4ef R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000512
R13: 00000000000927c0 R14: 0000000000070d69 R15: 00007ffe35aed4b0
 </TASK>