syzbot

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WARNING: CPU: 1 PID: 3585 at kernel/rcu/tree_stall.h:953 rcu_check_gp_start_stall+0x2c8/0x450 kernel/rcu/tree_stall.h:938
Modules linked in:
CPU: 1 PID: 3585 Comm: syz-executor152 Not tainted 6.1.53-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
RIP: 0010:rcu_check_gp_start_stall+0x2c8/0x450 kernel/rcu/tree_stall.h:953
Code: c7 c7 40 bf cd 91 be 04 00 00 00 e8 02 1e 6d 00 b8 01 00 00 00 87 05 67 25 5a 10 85 c0 0f 85 1c ff ff ff 48 c7 c0 40 ee 12 8d <0f> 0b 49 39 c7 74 47 48 c7 c0 24 e8 73 8e 48 c1 e8 03 42 0f b6 04
RSP: 0018:ffffc900001e0bb8 EFLAGS: 00010046
RAX: ffffffff8d12ee40 RBX: 0000000100003d9a RCX: ffffffff817399ce
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff91cdbf40
RBP: ffffc900001e0df0 R08: dffffc0000000000 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8880b993ad60 R14: 0000000000000246 R15: ffffffff8d12ee40
FS:  00007ff9440536c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff944032d58 CR3: 0000000021843000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_core+0x67f/0x1790 kernel/rcu/tree.c:2506
 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x155/0x240 kernel/softirq.c:650
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:finish_lock_switch+0x91/0x100 kernel/sched/core.c:5001
Code: 45 31 c9 68 97 43 60 81 e8 ac b1 09 00 48 83 c4 08 4c 89 ff e8 c0 cc fe ff 66 90 4c 89 ff e8 06 a9 2f 09 e8 a1 89 30 00 fb 5b <41> 5c 41 5d 41 5e 41 5f c3 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 87
RSP: 0018:ffffc90003bdf298 EFLAGS: 00000286
RAX: b844a98fb0107800 RBX: ffff888023871df4 RCX: ffffffff91c97103
RDX: dffffc0000000000 RSI: ffffffff8aebe2a0 RDI: ffffffff8b3ceb80
RBP: ffffc90003bdf310 R08: dffffc0000000000 R09: ffffed10173273c1
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff1101732756b R14: ffff8880b993ab58 R15: ffff8880b9939e00
 finish_task_switch+0x134/0x630 kernel/sched/core.c:5118
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x1334/0x4330 kernel/sched/core.c:6554
 schedule+0xbf/0x180 kernel/sched/core.c:6630
 schedule_timeout+0xac/0x300 kernel/time/timer.c:1911
 unix_wait_for_peer+0x24b/0x330 net/unix/af_unix.c:1449
 unix_dgram_sendmsg+0x1348/0x2050 net/unix/af_unix.c:2047
 sock_sendmsg_nosec net/socket.c:716 [inline]
 sock_sendmsg net/socket.c:736 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2482
 ___sys_sendmsg net/socket.c:2536 [inline]
 __sys_sendmmsg+0x3ab/0x730 net/socket.c:2622
 __do_sys_sendmmsg net/socket.c:2651 [inline]
 __se_sys_sendmmsg net/socket.c:2648 [inline]
 __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2648
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7ff944092599
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff944053228 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007ff9440536c0 RCX: 00007ff944092599
RDX: 0000000000000318 RSI: 00000000200bd000 RDI: 0000000000000004
RBP: 00007ff94411c328 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff94411c320
R13: 00007ff9440e9064 R14: 00007fff1f08b9f0 R15: 00007fff1f08bad8
 </TASK>
----------------
Code disassembly (best guess):
   0:	45 31 c9             	xor    %r9d,%r9d
   3:	68 97 43 60 81       	push   $0xffffffff81604397
   8:	e8 ac b1 09 00       	call   0x9b1b9
   d:	48 83 c4 08          	add    $0x8,%rsp
  11:	4c 89 ff             	mov    %r15,%rdi
  14:	e8 c0 cc fe ff       	call   0xfffeccd9
  19:	66 90                	xchg   %ax,%ax
  1b:	4c 89 ff             	mov    %r15,%rdi
  1e:	e8 06 a9 2f 09       	call   0x92fa929
  23:	e8 a1 89 30 00       	call   0x3089c9
  28:	fb                   	sti
  29:	5b                   	pop    %rbx
* 2a:	41 5c                	pop    %r12 <-- trapping instruction
  2c:	41 5d                	pop    %r13
  2e:	41 5e                	pop    %r14
  30:	41 5f                	pop    %r15
  32:	c3                   	ret
  33:	44 89 f1             	mov    %r14d,%ecx
  36:	80 e1 07             	and    $0x7,%cl
  39:	80 c1 03             	add    $0x3,%cl
  3c:	38 c1                	cmp    %al,%cl
  3e:	7c 87                	jl     0xffffffc7