syzbot


INFO: rcu detected stall in lapb_t1timer_expiry

Status: auto-closed as invalid on 2022/06/25 00:02
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 221d, last: 221d

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10499 ticks this GP) idle=613/1/0x4000000000000000 softirq=44916/44916 fqs=22 
	(t=10501 jiffies g=55989 q=53 ncpus=2)
rcu: rcu_preempt kthread starved for 10446 jiffies! g55989 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:28680 pid:   16 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5106 [inline]
 __schedule+0xa9a/0x4cc0 kernel/sched/core.c:6421
 schedule+0xd2/0x1f0 kernel/sched/core.c:6493
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1907
 rcu_gp_fqs_loop+0x1c0/0x840 kernel/rcu/tree.c:2078
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2267
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
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: 14797 Comm: syz-executor.0 Not tainted 5.18.0-rc3-next-20220422-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:kvm_wait+0x98/0x100 arch/x86/kernel/kvm.c:1058
Code: fa 83 e2 07 38 d0 7f 04 84 c0 75 63 0f b6 07 40 38 c6 74 35 48 83 c4 10 c3 c3 e8 23 91 4b 00 eb 07 0f 00 2d da b1 94 08 fb f4 <48> 83 c4 10 c3 89 74 24 0c 48 89 3c 24 e8 56 8f 4b 00 8b 74 24 0c
RSP: 0018:ffffc90002bafc08 EFLAGS: 00000246
RAX: 0000000000000007 RBX: ffff8880b9d3ae40 RCX: 1ffffffff1b73199
RDX: 0000000000000000 RSI: ffffffff81807171 RDI: ffffffff8134dffd
RBP: ffff8880b9c3ae54 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff81807158 R11: 0000000000000000 R12: ffffed10173a75ca
R13: ffff8880b9d3ae54 R14: dffffc0000000000 R15: ffff8880b9c3ae40
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2dc4d000 CR3: 0000000078990000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000003b DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:603 [inline]
 pv_wait_node kernel/locking/qspinlock_paravirt.h:325 [inline]
 __pv_queued_spin_lock_slowpath+0x6d8/0xb50 kernel/locking/qspinlock.c:476
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock+0x200/0x2a0 kernel/locking/spinlock_debug.c:115
 spin_lock include/linux/spinlock.h:354 [inline]
 task_lock include/linux/sched/task.h:170 [inline]
 mm_update_next_owner+0x21a/0x7a0 kernel/exit.c:457
 exit_mm kernel/exit.c:509 [inline]
 do_exit+0xa0a/0x2a00 kernel/exit.c:782
 do_group_exit+0xd2/0x2f0 kernel/exit.c:925
 __do_sys_exit_group kernel/exit.c:936 [inline]
 __se_sys_exit_group kernel/exit.c:934 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:934
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fc7780890e9
Code: Unable to access opcode bytes at RIP 0x7fc7780890bf.
RSP: 002b:00007ffe9bd28308 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000000000000001e RCX: 00007fc7780890e9
RDX: 00007fc77803bd2b RSI: ffffffffffffffb8 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000074cbe9ed R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffe9bd283f0
 </TASK>
NMI backtrace for cpu 1
CPU: 1 PID: 14799 Comm: syz-executor.0 Not tainted 5.18.0-rc3-next-20220422-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x262/0x3f0 kernel/rcu/tree_stall.h:369
 print_cpu_stall kernel/rcu/tree_stall.h:665 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:749 [inline]
 rcu_pending kernel/rcu/tree.c:4068 [inline]
 rcu_sched_clock_irq.cold+0x144/0x8fc kernel/rcu/tree.c:2755
 update_process_times+0x16d/0x200 kernel/time/timer.c:1811
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:243
 tick_sched_timer+0xee/0x120 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1106
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:kvm_wait+0x98/0x100 arch/x86/kernel/kvm.c:1058
Code: fa 83 e2 07 38 d0 7f 04 84 c0 75 63 0f b6 07 40 38 c6 74 35 48 83 c4 10 c3 c3 e8 23 91 4b 00 eb 07 0f 00 2d da b1 94 08 fb f4 <48> 83 c4 10 c3 89 74 24 0c 48 89 3c 24 e8 56 8f 4b 00 8b 74 24 0c
RSP: 0018:ffffc90000de02c8 EFLAGS: 00000246
RAX: 0000000000000007 RBX: 0000000000000000 RCX: 1ffffffff1b73199
RDX: 0000000000000000 RSI: ffffffff81807171 RDI: ffffffff8134dffd
RBP: ffff8880244a0948 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff81807158 R11: 0000000000000001 R12: 0000000000000000
R13: ffffed1004894129 R14: 0000000000000001 R15: ffff8880b9d3ae40
 pv_wait arch/x86/include/asm/paravirt.h:603 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x8c7/0xb50 kernel/locking/qspinlock.c:511
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock+0x200/0x2a0 kernel/locking/spinlock_debug.c:115
 spin_lock include/linux/spinlock.h:354 [inline]
 task_lock include/linux/sched/task.h:170 [inline]
 __get_task_comm+0x23/0x50 fs/exec.c:1219
 __set_page_owner_handle mm/page_owner.c:174 [inline]
 __set_page_owner+0x253/0x380 mm/page_owner.c:192
 prep_new_page mm/page_alloc.c:2394 [inline]
 get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4135
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5356
 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2273
 alloc_slab_page mm/slub.c:1797 [inline]
 allocate_slab+0x26c/0x3c0 mm/slub.c:1942
 new_slab mm/slub.c:2002 [inline]
 ___slab_alloc+0x985/0xd90 mm/slub.c:3002
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3089
 slab_alloc_node mm/slub.c:3180 [inline]
 slab_alloc mm/slub.c:3222 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3229 [inline]
 kmem_cache_alloc+0x360/0x3b0 mm/slub.c:3239
 skb_clone+0x170/0x3c0 net/core/skbuff.c:1520
 dev_queue_xmit_nit+0x393/0xb20 net/core/dev.c:2263
 xmit_one net/core/dev.c:3532 [inline]
 dev_hard_start_xmit+0xad/0x920 net/core/dev.c:3553
 __dev_queue_xmit+0x2cbf/0x3b10 net/core/dev.c:4208
 lapb_data_transmit+0x8f/0xc0 net/lapb/lapb_iface.c:447
 lapb_transmit_buffer+0x183/0x390 net/lapb/lapb_out.c:149
 lapb_send_control+0x1c7/0x370 net/lapb/lapb_subr.c:251
 lapb_t1timer_expiry+0x5c6/0x8d0 net/lapb/lapb_timer.c:142
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1444
 expire_timers kernel/time/timer.c:1489 [inline]
 __run_timers.part.0+0x679/0xa80 kernel/time/timer.c:1760
 __run_timers kernel/time/timer.c:1738 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1773
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:check_region_inline mm/kasan/generic.c:175 [inline]
RIP: 0010:kasan_check_range+0x27/0x180 mm/kasan/generic.c:189
Code: 00 00 00 48 85 f6 0f 84 3c 01 00 00 49 89 f9 41 54 44 0f b6 c2 49 01 f1 55 53 0f 82 18 01 00 00 48 b8 ff ff ff ff ff 7f ff ff <48> 39 c7 0f 86 05 01 00 00 49 83 e9 01 48 89 fd 48 b8 00 00 00 00
RSP: 0018:ffffc90002bdef40 EFLAGS: 00000282
RAX: ffff7fffffffffff RBX: ffff8880244a0000 RCX: ffffffff815ea4d0
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880244a0948
RBP: ffff8880244a0948 R08: 0000000000000000 R09: ffff8880244a094c
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88801337d668
R13: 0000000000000010 R14: ffff88801337d648 R15: 0000000000000007
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
 queued_spin_is_locked include/asm-generic/qspinlock.h:28 [inline]
 debug_spin_unlock kernel/locking/spinlock_debug.c:100 [inline]
 do_raw_spin_unlock+0x50/0x230 kernel/locking/spinlock_debug.c:140
 __raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_unlock+0x1a/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:394 [inline]
 task_unlock include/linux/sched/task.h:175 [inline]
 __get_task_comm+0x3d/0x50 fs/exec.c:1222
 __set_page_owner_handle mm/page_owner.c:174 [inline]
 __set_page_owner+0x253/0x380 mm/page_owner.c:192
 prep_new_page mm/page_alloc.c:2394 [inline]
 get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4135
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5356
 alloc_pages_vma+0xf9/0x770 mm/mempolicy.c:2221
 wp_page_copy+0xaef/0x1e20 mm/memory.c:3100
 do_wp_page+0x573/0x1b60 mm/memory.c:3397
 handle_pte_fault mm/memory.c:4922 [inline]
 __handle_mm_fault+0x1fe6/0x33d0 mm/memory.c:5043
 handle_mm_fault+0x1c8/0x790 mm/memory.c:5141
 do_user_addr_fault+0x489/0x11c0 arch/x86/mm/fault.c:1397
 handle_page_fault arch/x86/mm/fault.c:1484 [inline]
 exc_page_fault+0x9e/0x180 arch/x86/mm/fault.c:1540
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0010:copy_user_enhanced_fast_string+0xa/0x40 arch/x86/lib/copy_user_64.S:166
Code: ff c9 75 f2 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 8d 0c ca 89 ca eb 20 0f 01 cb 83 fa 40 72 38 89 d1 <f3> a4 31 c0 0f 01 ca c3 89 ca eb 0a 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90002bdf7a8 EFLAGS: 00050206
RAX: 0000000000000001 RBX: 0000000000001000 RCX: 0000000000000100
RDX: 0000000000001000 RSI: ffff88805e32cf00 RDI: 000000002014f000
RBP: 000000002014e100 R08: 0000000000000000 R09: ffff88805e32cfff
R10: ffffed100bc659ff R11: 0000000000000000 R12: ffff88805e32c000
R13: 00007fffffffe000 R14: 0000000000000000 R15: ffffc90002bdfd70
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline]
 copyout.part.0+0xd8/0x100 lib/iov_iter.c:155
 copyout lib/iov_iter.c:667 [inline]
 _copy_to_iter+0x2b9/0x1890 lib/iov_iter.c:667
 copy_to_iter include/linux/uio.h:162 [inline]
 simple_copy_to_iter+0x4c/0x70 net/core/datagram.c:518
 __skb_datagram_iter+0x4a5/0x770 net/core/datagram.c:447
 skb_copy_datagram_iter+0xa2/0x2c0 net/core/datagram.c:532
 skb_copy_datagram_msg include/linux/skbuff.h:3884 [inline]
 unix_stream_read_actor+0x78/0xc0 net/unix/af_unix.c:2884
 unix_stream_read_generic+0x80e/0x2150 net/unix/af_unix.c:2803
 unix_stream_recvmsg+0x187/0x1b0 net/unix/af_unix.c:2921
 sock_recvmsg_nosec net/socket.c:948 [inline]
 sock_recvmsg net/socket.c:966 [inline]
 sock_recvmsg net/socket.c:962 [inline]
 __sys_recvfrom+0x242/0x390 net/socket.c:2129
 __do_sys_recvfrom net/socket.c:2147 [inline]
 __se_sys_recvfrom net/socket.c:2143 [inline]
 __x64_sys_recvfrom+0xdd/0x1b0 net/socket.c:2143
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fc7780890e9
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc779178168 EFLAGS: 00000246 ORIG_RAX: 000000000000002d
RAX: ffffffffffffffda RBX: 00007fc77819bf60 RCX: 00007fc7780890e9
RDX: 00000000ffffffe8 RSI: 0000000020000100 RDI: 0000000000000006
RBP: 00007fc7780e308d R08: 0000000000000000 R09: ffffffffffffff49
R10: 0000000040012500 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe9bd280cf R14: 00007fc779178300 R15: 0000000000022000
 </TASK>
----------------
Code disassembly (best guess):
   0:	fa                   	cli
   1:	83 e2 07             	and    $0x7,%edx
   4:	38 d0                	cmp    %dl,%al
   6:	7f 04                	jg     0xc
   8:	84 c0                	test   %al,%al
   a:	75 63                	jne    0x6f
   c:	0f b6 07             	movzbl (%rdi),%eax
   f:	40 38 c6             	cmp    %al,%sil
  12:	74 35                	je     0x49
  14:	48 83 c4 10          	add    $0x10,%rsp
  18:	c3                   	retq
  19:	c3                   	retq
  1a:	e8 23 91 4b 00       	callq  0x4b9142
  1f:	eb 07                	jmp    0x28
  21:	0f 00 2d da b1 94 08 	verw   0x894b1da(%rip)        # 0x894b202
  28:	fb                   	sti
  29:	f4                   	hlt
* 2a:	48 83 c4 10          	add    $0x10,%rsp <-- trapping instruction
  2e:	c3                   	retq
  2f:	89 74 24 0c          	mov    %esi,0xc(%rsp)
  33:	48 89 3c 24          	mov    %rdi,(%rsp)
  37:	e8 56 8f 4b 00       	callq  0x4b8f92
  3c:	8b 74 24 0c          	mov    0xc(%rsp),%esi

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-linux-next-kasan-gce-root 2022/04/26 00:00 linux-next e7d6987e09a3 152baedd .config log report info INFO: rcu detected stall in lapb_t1timer_expiry
* Struck through repros no longer work on HEAD.