rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=8e3c/1/0x4000000000000000 softirq=88942/88943 fqs=139 rcu: (detected by 0, t=10505 jiffies, g=78517, q=58 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 17890 Comm: syz.2.2778 Not tainted 6.13.0-rc4-syzkaller-00078-g059dd502b263 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__sanitizer_cov_trace_const_cmp1+0xc/0x20 kernel/kcov.c:300 Code: 00 e9 b8 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 40 0f b6 d6 <40> 0f b6 f7 bf 01 00 00 00 e9 86 fe ff ff 66 0f 1f 44 00 00 90 90 RSP: 0018:ffffc90000a18df8 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffff8880b872cc00 RCX: ffffffff81874416 RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff88806bf89340 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000004 R12: 0000000000000001 R13: 0000000000000000 R14: ffff8880b872ca00 R15: ffffffff89415480 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020003c80 CR3: 000000000df7e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_hrtimer_start include/trace/events/timer.h:222 [inline] debug_activate kernel/time/hrtimer.c:470 [inline] enqueue_hrtimer+0x2f6/0x3c0 kernel/time/hrtimer.c:1076 __run_hrtimer kernel/time/hrtimer.c:1756 [inline] __hrtimer_run_queues+0x903/0xae0 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__sanitizer_cov_trace_pc+0x41/0x70 kernel/kcov.c:217 Code: 00 48 8b 34 24 74 1d f6 c4 01 74 43 a9 00 00 0f 00 75 3c a9 00 00 f0 00 75 35 8b 82 1c 16 00 00 85 c0 74 2b 8b 82 f8 15 00 00 <83> f8 02 75 20 48 8b 8a 00 16 00 00 8b 92 fc 15 00 00 48 8b 01 48 RSP: 0018:ffffc900063b7660 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81e39f8e RDX: ffff888088814880 RSI: ffffffff81e39af2 RDI: 0000000000000005 RBP: 0000000000000002 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000003 R12: dffffc0000000000 R13: 00007f5b0c61f000 R14: ffffea0000e47d80 R15: ffffc900063b7aa8 zap_present_folio_ptes mm/memory.c:1531 [inline] zap_present_ptes mm/memory.c:1585 [inline] zap_pte_range mm/memory.c:1627 [inline] zap_pmd_range mm/memory.c:1753 [inline] zap_pud_range mm/memory.c:1782 [inline] zap_p4d_range mm/memory.c:1803 [inline] unmap_page_range+0x1582/0x3d10 mm/memory.c:1824 unmap_single_vma+0x194/0x2b0 mm/memory.c:1870 unmap_vmas+0x22f/0x490 mm/memory.c:1914 exit_mmap+0x1c6/0xb20 mm/mmap.c:1668 __mmput+0x12a/0x4c0 kernel/fork.c:1348 mmput+0x62/0x70 kernel/fork.c:1370 exit_mm kernel/exit.c:570 [inline] do_exit+0x9ba/0x2d70 kernel/exit.c:925 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 get_signal+0x24ed/0x26c0 kernel/signal.c:3017 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [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+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5b0d785d29 Code: Unable to access opcode bytes at 0x7f5b0d785cff. RSP: 002b:00007f5b0e59e0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007f5b0d975fa8 RCX: 00007f5b0d785d29 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f5b0d975fac RBP: 00007f5b0d975fa0 R08: 00007f5b0e59f000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5b0d975fac R13: 0000000000000000 R14: 00007ffd05667480 R15: 00007ffd05667568 rcu: rcu_preempt kthread starved for 9810 jiffies! g78517 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:25552 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.13.0-rc4-syzkaller-00078-g059dd502b263 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline] RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 05 d8 f4 d9 74 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 68 a1 b3 00 fb f4 c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8de07d70 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8b29c759 RDX: 0000000000000001 RSI: ffff888020ef6800 RDI: ffff888020ef6864 RBP: ffff888020ef6864 R08: 0000000000000001 R09: ffffed10170c6fed R10: ffff8880b8637f6b R11: 0000000000000000 R12: ffff8880213b8000 R13: ffffffff8ee16aa0 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff96edf5f98 CR3: 0000000067fbe000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:699 cpuidle_enter_state+0xaa/0x4f0 drivers/cpuidle/cpuidle.c:268 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:389 cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x310/0x3f0 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 rest_init+0x16b/0x2b0 init/main.c:747 start_kernel+0x3e4/0x4d0 init/main.c:1102 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x148