sched: RT throttling activated rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=6441, q=246 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294956294-4294945792), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g6441 f0x2 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:27880 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0xb8a/0x5450 kernel/sched/core.c:6555 schedule+0xde/0x1b0 kernel/sched/core.c:6631 schedule_timeout+0x14e/0x2a0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1654 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1853 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5309 Comm: syz-executor.3 Not tainted 6.1.0-syzkaller-12648-g6feb57c2fd7c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x8/0x20 kernel/kcov.c:310 Code: 00 00 f3 0f 1e fa 48 8b 0c 24 89 f2 89 fe bf 05 00 00 00 e9 9a fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 8b 0c 24 <48> 89 f2 48 89 fe bf 07 00 00 00 e9 78 fe ff ff 0f 1f 84 00 00 00 RSP: 0018:ffffc90000007ba8 EFLAGS: 00000046 RAX: 0000000080010001 RBX: 0000000000000000 RCX: ffffffff81719a1b RDX: ffff88802a6e3a80 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000008bfa R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88802a1254f0 R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b982b800 FS: 00007f0901636700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0901615718 CR3: 000000002108d000 CR4: 0000000000350ef0 Call Trace: seqcount_lockdep_reader_access include/linux/seqlock.h:101 [inline] timekeeping_get_delta kernel/time/timekeeping.c:254 [inline] timekeeping_get_ns kernel/time/timekeeping.c:388 [inline] ktime_get+0x11b/0x470 kernel/time/timekeeping.c:848 hrtimer_forward_now include/linux/hrtimer.h:506 [inline] perf_swevent_hrtimer+0x21d/0x3c0 kernel/events/core.c:10973 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c6/0xfb0 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x320/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline] __sysvec_apic_timer_interrupt+0x180/0x640 arch/x86/kernel/apic/apic.c:1113 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x3c/0x70 kernel/locking/spinlock.c:194 Code: 74 24 10 e8 a6 08 5b f7 48 89 ef e8 4e 75 5b f7 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 8f d8 4d f7 65 8b 05 40 c5 fa 75 85 c0 74 0a 5b 5d c3 e8 2c ed RSP: 0018:ffffc90004f47208 EFLAGS: 00000206 RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff226de76 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffffffff91e35d38 R08: 0000000000000001 R09: ffffffff91335b5f R10: 0000000000000001 R11: 0000000000000000 R12: 1ffffffff23c6ba6 R13: 0000000000000000 R14: dead000000000100 R15: dffffc0000000000 __debug_check_no_obj_freed lib/debugobjects.c:1006 [inline] debug_check_no_obj_freed+0x210/0x420 lib/debugobjects.c:1027 slab_free_hook mm/slub.c:1756 [inline] slab_free_freelist_hook+0xeb/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] kmem_cache_free+0xee/0x5c0 mm/slub.c:3809 jbd2_free_handle include/linux/jbd2.h:1601 [inline] jbd2_journal_stop+0x68f/0xfb0 fs/jbd2/transaction.c:1956 __ext4_journal_stop+0xe2/0x1f0 fs/ext4/ext4_jbd2.c:133 ext4_dirty_inode+0xf1/0x130 fs/ext4/inode.c:6111 __mark_inode_dirty+0x247/0x11e0 fs/fs-writeback.c:2419 mark_inode_dirty include/linux/fs.h:2462 [inline] generic_write_end+0x354/0x440 fs/buffer.c:2184 ext4_da_write_end+0x1f5/0xa30 fs/ext4/inode.c:3175 generic_perform_write+0x316/0x570 mm/filemap.c:3783 ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:285 ext4_file_write_iter+0x8bf/0x1710 fs/ext4/file.c:700 call_write_iter include/linux/fs.h:2186 [inline] do_iter_readv_writev+0x20b/0x3b0 fs/read_write.c:735 do_iter_write+0x182/0x700 fs/read_write.c:861 vfs_iter_write+0x74/0xa0 fs/read_write.c:902 iter_file_splice_write+0x745/0xc90 fs/splice.c:686 do_splice_from fs/splice.c:764 [inline] direct_splice_actor+0x114/0x180 fs/splice.c:931 splice_direct_to_actor+0x335/0x8a0 fs/splice.c:886 do_splice_direct+0x1ab/0x280 fs/splice.c:974 do_sendfile+0xb19/0x1270 fs/read_write.c:1255 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64 fs/read_write.c:1309 [inline] __x64_sys_sendfile64+0x14d/0x210 fs/read_write.c:1309 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x45f679 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f09016361a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 000000000052bfa0 RCX: 000000000045f679 RDX: 0000000020000000 RSI: 0000000000000003 RDI: 0000000000000003 RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000 R10: 00008080fffffffe R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004f0998 R14: 00000000004b0443 R15: 00007f09016366bc INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.554 msecs