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WARNING: CPU: 1 PID: 10800 at kernel/rcu/tree_stall.h:1001 rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:993
Modules linked in:
CPU: 1 PID: 10800 Comm: vhost-10799 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:1001
Code: ff ff ff 48 c7 c7 a0 a4 30 97 be 04 00 00 00 e8 1a d3 6d 00 48 89 df b8 01 00 00 00 87 05 7c 2a bf 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff c0 72 13 8d 74 47 48 c7 c0 ac 23 8b 8e 48 c1 e8 03
RSP: 0018:ffffc900001f0bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8d1372c0 RCX: ffffffff81717a16
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8d1372c0
RBP: ffffc900001f0e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff2e61494 R12: 0000000000002904
R13: ffffffff8d1372c0 R14: 0000000000000a02 R15: dffffc0000000000
FS:  00007f4cbfbdb6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000002 CR3: 0000000053c47000 CR4: 00000000003506e0
Call Trace:
 <IRQ>
 rcu_core+0x635/0x1770 kernel/rcu/tree.c:2462
 handle_softirqs+0x280/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:lock_acquire+0x208/0x420 kernel/locking/lockdep.c:5758
Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3c 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 43 c7 44 3c 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc90003397740 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: a0b84f1c5bfeca00
RDX: 0000000000000000 RSI: ffffffff8acadae0 RDI: ffffffff8b1c85a0
RBP: ffffc90003397848 R08: dffffc0000000000 R09: 1ffffffff22382a6
R10: dffffc0000000000 R11: fffffbfff22382a7 R12: 1ffff92000672ef4
R13: ffff888079aa14a0 R14: 0000000000000246 R15: dffffc0000000000
 internal_get_user_pages_fast+0x215/0x2760 mm/gup.c:3209
 set_bit_to_user drivers/vhost/vhost.c:2194 [inline]
 log_write+0xc3/0x370 drivers/vhost/vhost.c:2220
 vhost_update_used_flags+0x1c3/0x290 drivers/vhost/vhost.c:2339
 vhost_disable_notify+0xad/0x1b0 drivers/vhost/vhost.c:2947
 vhost_vsock_handle_tx_kick+0x15e/0xd80 drivers/vhost/vsock.c:487
 vhost_run_work_list+0x13d/0x1b0 drivers/vhost/vhost.c:419
 vhost_task_fn+0x2df/0x460 kernel/vhost_task.c:49
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
----------------
Code disassembly (best guess):
   0:	f7 84 24 80 00 00 00 	testl  $0x200,0x80(%rsp)
   7:	00 02 00 00
   b:	43 c6 44 3c 04 f8    	movb   $0xf8,0x4(%r12,%r15,1)
  11:	0f 85 f0 00 00 00    	jne    0x107
  17:	41 f7 c6 00 02 00 00 	test   $0x200,%r14d
  1e:	74 01                	je     0x21
  20:	fb                   	sti
  21:	48 c7 44 24 60 0e 36 	movq   $0x45e0360e,0x60(%rsp)
  28:	e0 45
* 2a:	4b c7 04 3c 00 00 00 	movq   $0x0,(%r12,%r15,1) <-- trapping instruction
  31:	00
  32:	43 c7 44 3c 08 00 00 	movl   $0x0,0x8(%r12,%r15,1)
  39:	00 00
  3b:	65                   	gs
  3c:	48                   	rex.W
  3d:	8b                   	.byte 0x8b
  3e:	04 25                	add    $0x25,%al