rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=323c/1/0x4000000000000000 softirq=90735/90736 fqs=4 rcu: (detected by 0, t=10506 jiffies, g=93097, q=397 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 20116 Comm: syz.2.3400 Not tainted 6.13.0-rc6-syzkaller-00290-gbe548645527a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0xc/0x70 kernel/kcov.c:217 Code: cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 48 8b 15 94 c4 69 7e <65> 8b 05 95 c4 69 7e a9 00 01 ff 00 48 8b 34 24 74 1d f6 c4 01 74 RSP: 0018:ffffc90000a18d78 EFLAGS: 00000002 RAX: 0000000080010001 RBX: 0000000000000001 RCX: ffffffff89418837 RDX: ffff88806aa14880 RSI: 0000000000000000 RDI: 0000000000000005 RBP: ffff888035676410 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000002 R13: ffff888035676400 R14: ffff88802a3be340 R15: ffff888035675c00 FS: 00007fd1320596c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd13111cf30 CR3: 00000000502b6000 CR4: 00000000003526f0 DR0: 0000000000000b00 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: rcu_read_unlock include/linux/rcupdate.h:878 [inline] advance_sched+0x894/0xc60 net/sched/sch_taprio.c:987 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x20a/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:deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] RIP: 0010:unwind_next_frame+0xaba/0x20c0 arch/x86/kernel/unwind_orc.c:585 Code: e9 a5 f6 ff ff e8 36 6d b3 00 e9 62 f6 ff ff e8 fc 9a c2 ff e9 f0 f8 ff ff 4d 8d 7e f8 ba 08 00 00 00 4c 89 ef 4c 89 4c 24 20 <4c> 89 fe 48 89 4c 24 18 e8 29 f3 ff ff 4d 8d 45 34 84 c0 0f 84 81 RSP: 0018:ffffc9000436f728 EFLAGS: 00000246 RAX: 0000000000000002 RBX: 0000000000000001 RCX: ffffffff90f0a4d4 RDX: 0000000000000008 RSI: 0000000000000001 RDI: ffffc9000436f7e8 RBP: ffffc9000436f830 R08: ffffffff90f0a4e6 R09: ffffffff90f0a4d8 R10: ffffc9000436f7e8 R11: 000000000000406e R12: ffffc9000436f838 R13: ffffc9000436f7e8 R14: ffffc9000436f888 R15: ffffc9000436f880 __unwind_start+0x45f/0x7f0 arch/x86/kernel/unwind_orc.c:760 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0x74/0x100 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4298 [inline] __kmalloc_noprof+0x21c/0x510 mm/slub.c:4310 kmalloc_noprof include/linux/slab.h:905 [inline] tomoyo_realpath_from_path+0xb9/0x720 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x248/0x590 security/tomoyo/file.c:723 security_file_ioctl+0x9b/0x240 security/security.c:2908 __do_sys_ioctl fs/ioctl.c:900 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0xb7/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd13118592b Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007fd132059060 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd13118592b RDX: 0000000000000000 RSI: 0000000000006364 RDI: 00000000000000d8 RBP: 00007fd131375fa0 R08: 0000000000000000 R09: 00007ffd6bb22247 R10: 0000000000000008 R11: 0000000000000246 R12: 00007fd131375fac R13: 0000000000000001 R14: 00007ffd6bb22160 R15: 00007ffd6bb22248 rcu: rcu_preempt kthread starved for 10485 jiffies! g93097 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:28424 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: 20125 Comm: syz.4.3401 Not tainted 6.13.0-rc6-syzkaller-00290-gbe548645527a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__sanitizer_cov_trace_pc+0x5a/0x70 kernel/kcov.c:223 Code: 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 83 c0 01 <48> 39 d0 73 07 48 89 01 48 89 34 c1 c3 cc cc cc cc 0f 1f 44 00 00 RSP: 0018:ffffc9000425fb28 EFLAGS: 00000216 RAX: 0000000000080000 RBX: ffff8880b8744a40 RCX: ffffc90004961000 RDX: 0000000000080000 RSI: ffffffff818e08b6 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000005 R12: ffffed10170e8949 R13: 0000000000000001 R14: ffff8880b8744a48 R15: ffff8880b863fe40 FS: 00007f00d05fd6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32c1fffc CR3: 00000000502ac000 CR4: 00000000003526f0 DR0: 0000000000000b00 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline] cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline] csd_lock_wait kernel/smp.c:340 [inline] smp_call_function_many_cond+0x456/0x1300 kernel/smp.c:884 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2114 [inline] text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_flush arch/x86/kernel/alternative.c:2512 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2522 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:920 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 __sched_core_enable kernel/sched/core.c:432 [inline] sched_core_get+0x8a/0xa0 kernel/sched/core.c:456 sched_core_alloc_cookie kernel/sched/core_sched.c:18 [inline] sched_core_share_pid+0x41f/0xa00 kernel/sched/core_sched.c:185 __do_sys_prctl+0x15e6/0x2190 kernel/sys.c:2741 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f00cf785d29 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:00007f00d05fd038 EFLAGS: 00000246 ORIG_RAX: 000000000000009d RAX: ffffffffffffffda RBX: 00007f00cf975fa0 RCX: 00007f00cf785d29 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 000000000000003e RBP: 00007f00cf801b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f00cf975fa0 R15: 00007fffd8d1b078