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WARNING: CPU: 0 PID: 6505 at kernel/rcu/tree_stall.h:1015 rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1015
Modules linked in:
CPU: 0 UID: 0 PID: 6505 Comm: syz.4.176 Not tainted 6.16.0-rc3-syzkaller-ge34a79b96ab9 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1015
Code: ff ff 48 c7 c7 40 74 ac 99 be 04 00 00 00 e8 03 2e 7c 00 4c 89 f7 b8 01 00 00 00 87 05 65 cd 04 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 00 42 14 8e 74 47 48 c7 c0 30 3e a1 8f 48 c1 e8
RSP: 0018:ffffc90000007bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000a02 RCX: ffffffff81a7a6cd
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8e144200
RBP: ffffc90000007e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff3358e88 R12: 0000000000002904
R13: 1ffff110170c75f2 R14: ffffffff8e144200 R15: dffffc0000000000
FS:  00007f5cc3b676c0(0000) GS:ffff888125c50000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9a99fa7f98 CR3: 0000000068904000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_core+0x5f7/0x1710 kernel/rcu/tree.c:2827
 handle_softirqs+0x286/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0xa3/0xc0 arch/x86/kernel/irq_work.c:17
 </IRQ>
 <TASK>
 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738
RIP: 0010:rcu_read_unlock_special+0x87/0x4c0 kernel/rcu/tree_plugin.h:694
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 a2 35 f5 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
RSP: 0018:ffffc9001b4c64a0 EFLAGS: 00000206
RAX: 30a74626ca38ed00 RBX: 1ffff92003698c9c RCX: 30a74626ca38ed00
RDX: 0000000000000006 RSI: ffffffff8d982385 RDI: ffffffff8be28d40
RBP: ffffc9001b4c6598 R08: ffffffff8fa10cf7 R09: 1ffffffff1f4219e
R10: dffffc0000000000 R11: fffffbfff1f4219f R12: ffffffff8e144200
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x84/0xe0 kernel/rcu/tree_plugin.h:438
 rcu_read_unlock include/linux/rcupdate.h:873 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0x19ae/0x2390 arch/x86/kernel/unwind_orc.c:680
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf5/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 free_unref_folios+0xc66/0x14d0 mm/page_alloc.c:2763
 folios_put_refs+0x559/0x640 mm/swap.c:992
 folios_put include/linux/mm.h:1415 [inline]
 folio_batch_move_lru+0x319/0x3a0 mm/swap.c:175
 __folio_batch_add_and_move+0x5ad/0xd20 mm/swap.c:196
 shmem_alloc_and_add_folio+0xcb3/0xf60 mm/shmem.c:1949
 shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2536
 shmem_get_folio mm/shmem.c:2642 [inline]
 shmem_write_begin+0xf7/0x2b0 mm/shmem.c:3292
 generic_perform_write+0x2c7/0x910 mm/filemap.c:4112
 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3467
 __kernel_write_iter+0x390/0x860 fs/read_write.c:619
 dump_emit_page fs/coredump.c:1112 [inline]
 dump_user_range+0x873/0xc70 fs/coredump.c:1186
 elf_core_dump+0x32ed/0x3900 fs/binfmt_elf.c:2075
 do_coredump+0x2806/0x3440 fs/coredump.c:950
 get_signal+0x1109/0x1340 kernel/signal.c:3019
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 irqentry_exit_to_user_mode+0x81/0x120 kernel/entry/common.c:184
 exc_page_fault+0x9f/0xf0 arch/x86/mm/fault.c:1535
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x41ed01b6031b
Code: Unable to access opcode bytes at 0x41ed01b602f1.
RSP: 002b:00002000000004a8 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f5cc2fb5fa0 RCX: 00007f5cc2d8e929
RDX: 00002000000004c0 RSI: 00002000000004a0 RDI: 0000000020004000
RBP: 00007f5cc2e10b39 R08: 0000200000000540 R09: 0000200000000540
R10: 0000200000000500 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f5cc2fb5fa0 R15: 00007ffc36482a58
 </TASK>
----------------
Code disassembly (best guess):
   0:	f1                   	int1
   1:	f1                   	int1
   2:	f1                   	int1
   3:	00 f2                	add    %dh,%dl
   5:	f2 f2 4a 89 04 2b    	repnz repnz mov %rax,(%rbx,%r13,1)
   b:	66 42 c7 44 2b 09 f3 	movw   $0xf3f3,0x9(%rbx,%r13,1)
  12:	f3
  13:	42 c6 44 2b 0b f3    	movb   $0xf3,0xb(%rbx,%r13,1)
  19:	65 44 8b 35 a2 35 f5 	mov    %gs:0x10f535a2(%rip),%r14d        # 0x10f535c3
  20:	10
  21:	41 f7 c6 00 00 f0 00 	test   $0xf00000,%r14d
  28:	74 49                	je     0x73
* 2a:	48 c7 44 24 40 0e 36 	movq   $0x45e0360e,0x40(%rsp) <-- trapping instruction
  31:	e0 45
  33:	4a c7 04 2b 00 00 00 	movq   $0x0,(%rbx,%r13,1)
  3a:	00
  3b:	66                   	data16
  3c:	42                   	rex.X
  3d:	c7                   	.byte 0xc7
  3e:	44                   	rex.R
  3f:	2b                   	.byte 0x2b