rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10513 ticks this GP) idle=286c/1/0x4000000000000000 softirq=18034/18040 fqs=5250
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:  1032814          0            0
rcu: 	cputime:    24113      28386           82   ==> 52510(ms)
rcu: 	(t=10502 jiffies g=8809 q=3490 ncpus=2)
CPU: 0 UID: 0 PID: 6860 Comm: syz.0.448 Not tainted 6.16.0-rc6-syzkaller-00434-gcd7c97f4584a-dirty #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:rcu_read_unlock_special+0x90/0x4c0
Code: 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 92 37 f8 10 41 f7 c6 00 00 f0 00 74 49 48 c7 44 24 40 0e 36 e0 45 <4a> c7 04 2b 00 00 00 00 66 42 c7 44 2b 09 00 00 42 c6 44 2b 0b 00
RSP: 0018:ffffc900000075c0 EFLAGS: 00000206
RAX: 8f7593ea1aa27d00 RBX: 1ffff92000000ec0 RCX: 8f7593ea1aa27d00
RDX: 0000000000000002 RSI: ffffffff8d9987c6 RDI: ffffffff8be29f80
RBP: ffffc900000076b8 R08: ffffffff8fa1eaf7 R09: 1ffffffff1f43d5e
R10: dffffc0000000000 R11: fffffbfff1f43d5f R12: ffffffff8e144400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
FS:  00007fbc7b5426c0(0000) GS:ffff8880b861f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffddb95f010 CR3: 000000002a378000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __rcu_read_unlock+0x84/0xe0
 unwind_next_frame+0x19ae/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x62/0x70
 kmem_cache_free+0x18f/0x400
 delayed_put_task_struct+0x11f/0x2f0
 rcu_core+0xca8/0x1710
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:raw_spin_rq_unlock_irq+0x13/0x90
Code: cc e8 f1 7d db 09 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 53 66 90 e8 44 0b de 09 e8 bf 9f 34 00 fb 5b <41> 5e 41 5f c3 cc cc cc cc cc f3 0f 1e fa 49 be 00 00 00 00 00 fc
RSP: 0018:ffffc90003cef0c8 EFLAGS: 00000282
RAX: 8f7593ea1aa27d00 RBX: ffff888020d1a440 RCX: 8f7593ea1aa27d00
RDX: 0000000000000006 RSI: ffffffff8d9987c6 RDI: ffffffff8be29f80
RBP: ffffc90003cef2f0 R08: ffffffff8fa1eaf7 R09: 1ffffffff1f43d5e
R10: dffffc0000000000 R11: fffffbfff1f43d5f R12: ffff888020d19cc0
R13: dffffc0000000000 R14: ffff888020d19cc0 R15: ffff88804b039fc0
 __schedule+0x1948/0x4d00
 preempt_schedule_notrace+0xd1/0x110
 preempt_schedule_notrace_thunk+0x16/0x30
 lock_release+0x3ca/0x3e0
 __kmalloc_node_noprof+0xa9/0x4e0
 allocate_slab+0x17c/0x3b0
 ___slab_alloc+0xbfc/0x1480
 kmem_cache_alloc_lru_noprof+0x288/0x3d0
 proc_alloc_inode+0x2a/0xc0
 alloc_inode+0x6a/0x1b0
 new_inode+0x22/0x170
 proc_pid_make_inode+0x21/0x130
 proc_pident_instantiate+0x6d/0x2b0
 proc_pident_lookup+0x1b3/0x290
 __lookup_slow+0x297/0x3d0
 lookup_slow+0x53/0x70
 link_path_walk+0x935/0xea0
 path_openat+0x28c/0x3830
 do_filp_open+0x1fa/0x410
 do_sys_openat2+0x121/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbc7a78d310
Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 49 94 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 9c 94 02 00 8b 44
RSP: 002b:00007fbc7b541f10 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fbc7a78d310
RDX: 0000000000000002 RSI: 00007fbc7b541fa0 RDI: 00000000ffffff9c
RBP: 00007fbc7b541fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbc7a9b5fa0 R15: 00007ffc53ca6ee8
 </TASK>
sched: DL replenish lagged too much
