INFO: rcu_sched detected stalls on CPUs/tasks: (detected by 0, t=10502 jiffies, g=21089, c=21088, q=21) All QSes seen, last rcu_sched kthread activity 10495 (4295011588-4295001093), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.0 R running task 26736 2465 8332 0x0000000c Call Trace: sched_show_task kernel/sched/core.c:5168 [inline] sched_show_task.cold+0x2f0/0x351 kernel/sched/core.c:5143 print_other_cpu_stall kernel/rcu/tree.c:1501 [inline] check_cpu_stall kernel/rcu/tree.c:1616 [inline] __rcu_pending kernel/rcu/tree.c:3390 [inline] rcu_pending kernel/rcu/tree.c:3452 [inline] rcu_check_callbacks.cold+0xcb1/0xd0a kernel/rcu/tree.c:2792 update_process_times+0x31/0x70 kernel/time/timer.c:1590 tick_sched_handle+0x85/0x160 kernel/time/tick-sched.c:161 tick_sched_timer+0x43/0x130 kernel/time/tick-sched.c:1219 __run_hrtimer kernel/time/hrtimer.c:1223 [inline] __hrtimer_run_queues+0x270/0xbc0 kernel/time/hrtimer.c:1287 hrtimer_interrupt+0x1d8/0x5d0 kernel/time/hrtimer.c:1321 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline] smp_apic_timer_interrupt+0x11c/0x5e0 arch/x86/kernel/apic/apic.c:1100 apic_timer_interrupt+0x96/0xa0 arch/x86/entry/entry_64.S:792 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x54/0x90 kernel/locking/spinlock.c:200 RSP: 0018:ffff8880aec07df0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff10 RAX: 1ffffffff0fe2d2b RBX: ffff888055e6e828 RCX: 1ffff1100a53597e RDX: dffffc0000000000 RSI: ffff8880529acbd0 RDI: ffff8880529acb7c RBP: ffff8880aec07df8 R08: ffff8880529ac300 R09: ffff8880529acbf0 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880aec239c0 R13: ffff888055e6e7c0 R14: ffff8880aec239c0 R15: dffffc0000000000 expire_timers kernel/time/timer.c:1317 [inline] __run_timers kernel/time/timer.c:1636 [inline] __run_timers kernel/time/timer.c:1604 [inline] run_timer_softirq+0x5a5/0x1520 kernel/time/timer.c:1649 __do_softirq+0x244/0x9a0 kernel/softirq.c:288 invoke_softirq kernel/softirq.c:368 [inline] irq_exit+0x160/0x1b0 kernel/softirq.c:409 exiting_irq arch/x86/include/asm/apic.h:648 [inline] smp_apic_timer_interrupt+0x146/0x5e0 arch/x86/kernel/apic/apic.c:1102 apic_timer_interrupt+0x96/0xa0 arch/x86/entry/entry_64.S:792 RIP: 0010:__sanitizer_cov_trace_pc+0x41/0x60 kernel/kcov.c:87 RSP: 0018:ffff888055edf3b8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10 RAX: 0000000000040000 RBX: ffffffff88340fe0 RCX: ffffc90007e34000 RDX: 000000000003ffff RSI: ffffffff830ea4ec RDI: ffffffff87049140 RBP: ffff888055edf3b8 R08: 0000000000000000 R09: 0000000000000003 R10: 0000000000000000 R11: ffff8880529ac300 R12: 0000000000000001 R13: ffffffff87049100 R14: ffffffff87049140 R15: 0000000000000000 check_preemption_disabled+0x1c/0x250 lib/smp_processor_id.c:14 debug_smp_processor_id+0x1c/0x20 lib/smp_processor_id.c:57 rcu_lockdep_current_cpu_online kernel/rcu/tree.c:1186 [inline] rcu_lockdep_current_cpu_online+0x3a/0x140 kernel/rcu/tree.c:1177 rcu_read_lock_sched_held+0x97/0x130 kernel/rcu/update.c:113 trace_ext4_mark_inode_dirty include/trace/events/ext4.h:248 [inline] ext4_mark_inode_dirty+0x6bd/0x860 fs/ext4/inode.c:5919 ext4_dirty_inode+0x73/0xa0 fs/ext4/inode.c:5959 __mark_inode_dirty+0x54c/0x1040 fs/fs-writeback.c:2144 mark_inode_dirty include/linux/fs.h:2019 [inline] dquot_alloc_space include/linux/quotaops.h:315 [inline] dquot_alloc_block include/linux/quotaops.h:332 [inline] ext4_xattr_block_set+0x192c/0x2b00 fs/ext4/xattr.c:1996 ext4_xattr_set_handle+0x85a/0xda0 fs/ext4/xattr.c:2406 __ext4_set_acl+0x2ef/0x510 fs/ext4/acl.c:214 ext4_set_acl+0x20e/0x400 fs/ext4/acl.c:254 set_posix_acl fs/posix_acl.c:874 [inline] set_posix_acl+0x1e0/0x290 fs/posix_acl.c:857 posix_acl_xattr_set+0x88/0x120 fs/posix_acl.c:892 __vfs_setxattr+0xd8/0x130 fs/xattr.c:150 __vfs_setxattr_noperm+0x102/0x3c0 fs/xattr.c:181 vfs_setxattr+0xc5/0xf0 fs/xattr.c:224 setxattr+0x1de/0x350 fs/xattr.c:453 path_setxattr+0x11f/0x140 fs/xattr.c:472 SYSC_setxattr fs/xattr.c:487 [inline] SyS_setxattr+0x3b/0x50 fs/xattr.c:483 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45af49 RSP: 002b:00007f321aec4c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045af49 RDX: 0000000020000c40 RSI: 00000000200005c0 RDI: 0000000020000580 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000005c R11: 0000000000000246 R12: 00007f321aec56d4 R13: 00000000004c1ca0 R14: 00000000004e5cd0 R15: 00000000ffffffff rcu_sched kthread starved for 10495 jiffies! g21089 c21088 f0x2 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=1 rcu_sched R running task 29824 9 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384 schedule+0x92/0x1c0 kernel/sched/core.c:3428 schedule_timeout+0x43e/0xe10 kernel/time/timer.c:1746 rcu_gp_kthread+0xbf4/0x1ec0 kernel/rcu/tree.c:2255 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404