rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=8a9c/1/0x4000000000000000 softirq=106844/106845 fqs=3 rcu: (detected by 0, t=10502 jiffies, g=95261, q=194 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 19767 Comm: kworker/u8:13 Not tainted 6.14.0-rc2-syzkaller-00056-gab68d7eb7b1a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:__lock_acquire+0xc62/0x2100 kernel/locking/lockdep.c:5198 Code: 00 e8 92 65 00 00 45 31 f6 85 c0 0f 84 da 07 00 00 48 c7 c0 80 d9 3c 9a 48 c1 e8 03 48 bf 00 00 00 00 00 fc ff df 0f b6 04 38 <84> c0 0f 85 24 0d 00 00 83 3d 9f 1d a2 18 00 75 39 48 63 9c 24 88 RSP: 0018:ffffc90000a18a10 EFLAGS: 00000806 RAX: 0000000000000004 RBX: ffff888025eb8ad8 RCX: ffffffff819b21da RDX: 0000000000000000 RSI: 0000000000000008 RDI: dffffc0000000000 RBP: ffff888025eb8b90 R08: ffffffff942c6847 R09: 1ffffffff2858d08 R10: dffffc0000000000 R11: fffffbfff2858d09 R12: ffff888025eb8ad4 R13: ffff888025eb8000 R14: 0000000000000000 R15: ffff888025eb8bb0 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000563ae000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] advance_sched+0xa1e/0xca0 net/sched/sch_taprio.c:985 __run_hrtimer kernel/time/hrtimer.c:1801 [inline] __hrtimer_run_queues+0x59b/0xd30 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 de 93 32 f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 b3 af 9c f5 65 8b 05 a4 07 13 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc900048aea40 EFLAGS: 00000206 RAX: 64f4c2f047bdf000 RBX: 1ffff92000915d4c RCX: ffffffff819b21da RDX: dffffc0000000000 RSI: ffffffff8c0aa680 RDI: 0000000000000001 RBP: ffffc900048aead8 R08: ffffffff942c6847 R09: 1ffffffff2858d08 R10: dffffc0000000000 R11: fffffbfff2858d09 R12: dffffc0000000000 R13: 1ffff92000915d48 R14: ffffc900048aea60 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] rmqueue_bulk mm/page_alloc.c:2329 [inline] __rmqueue_pcplist+0x2231/0x2ad0 mm/page_alloc.c:3004 rmqueue_pcplist mm/page_alloc.c:3046 [inline] rmqueue mm/page_alloc.c:3077 [inline] get_page_from_freelist+0x88a/0x37a0 mm/page_alloc.c:3474 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4739 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2587 new_slab mm/slub.c:2640 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3826 __slab_alloc+0x58/0xa0 mm/slub.c:3916 __slab_alloc_node mm/slub.c:3991 [inline] slab_alloc_node mm/slub.c:4152 [inline] kmem_cache_alloc_noprof+0x268/0x380 mm/slub.c:4171 journal_alloc_journal_head fs/jbd2/journal.c:2821 [inline] jbd2_journal_add_journal_head+0x7e/0x470 fs/jbd2/journal.c:2889 jbd2_journal_get_write_access+0x1de/0x240 fs/jbd2/transaction.c:1241 __ext4_journal_get_write_access+0x1cc/0x580 fs/ext4/ext4_jbd2.c:239 ext4_reserve_inode_write+0x271/0x360 fs/ext4/inode.c:5831 __ext4_mark_inode_dirty+0x1ec/0x880 fs/ext4/inode.c:6005 ext4_dirty_inode+0xce/0x110 fs/ext4/inode.c:6042 __mark_inode_dirty+0x2ee/0xe90 fs/fs-writeback.c:2515 generic_update_time fs/inode.c:2112 [inline] inode_update_time fs/inode.c:2125 [inline] touch_atime+0x413/0x690 fs/inode.c:2197 file_accessed include/linux/fs.h:2601 [inline] filemap_read+0x100d/0x1260 mm/filemap.c:2763 __kernel_read+0x52e/0xa00 fs/read_write.c:523 elf_read fs/binfmt_elf.c:476 [inline] load_elf_binary+0x2096/0x2820 fs/binfmt_elf.c:918 search_binary_handler fs/exec.c:1775 [inline] exec_binprm fs/exec.c:1807 [inline] bprm_execve+0x979/0x1430 fs/exec.c:1859 kernel_execve+0x931/0xa50 fs/exec.c:2026 call_usermodehelper_exec_async+0x237/0x380 kernel/umh.c:109 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread starved for 10494 jiffies! g95261 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:26104 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x18bc/0x4c40 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6856 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 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: 19768 Comm: syz.6.2687 Not tainted 6.14.0-rc2-syzkaller-00056-gab68d7eb7b1a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x1ba4/0x2d30 kernel/smp.c:885 Code: 03 84 c0 75 7e 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 b0 e8 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 60 e4 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00 RSP: 0018:ffffc90004a6f3e0 EFLAGS: 00000246 RAX: ffffffff81b36b05 RBX: 1ffff110170e88c9 RCX: 0000000000080000 RDX: ffffc90015db7000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc90004a6f5e0 R08: ffffffff81b36ad0 R09: 1ffffffff2858d08 R10: dffffc0000000000 R11: fffffbfff2858d09 R12: ffff8880b863f9c8 R13: ffff8880b8744648 R14: ffff8880b863f9c0 R15: 0000000000000001 FS: 00007f1a9e99d6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d518ff8 CR3: 0000000034120000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2118 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2328 text_poke_bp+0xb0/0x100 arch/x86/kernel/alternative.c:2555 __static_call_transform+0x51a/0x810 arch/x86/kernel/static_call.c:111 arch_static_call_transform+0x141/0x380 arch/x86/kernel/static_call.c:163 __static_call_update+0xd8/0x5e0 kernel/static_call_inline.c:147 tracepoint_update_call kernel/tracepoint.c:271 [inline] tracepoint_add_func+0x925/0xaa0 kernel/tracepoint.c:312 tracepoint_probe_register_prio_may_exist+0x122/0x190 kernel/tracepoint.c:435 bpf_raw_tp_link_attach+0x4a3/0x700 kernel/bpf/syscall.c:3985 bpf_raw_tracepoint_open+0x177/0x1f0 kernel/bpf/syscall.c:4016 __sys_bpf+0x3c0/0x810 kernel/bpf/syscall.c:5836 __do_sys_bpf kernel/bpf/syscall.c:5901 [inline] __se_sys_bpf kernel/bpf/syscall.c:5899 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5899 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1a9db8cde9 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:00007f1a9e99d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f1a9dda6160 RCX: 00007f1a9db8cde9 RDX: 0000000000000018 RSI: 0000400000000540 RDI: 0000000000000011 RBP: 00007f1a9dc0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1a9dda6160 R15: 00007fff8ccffc98 vkms_vblank_simulate: vblank timer overrun