------------[ cut here ]------------
VFS: brelse: Trying to free free buffer
WARNING: CPU: 0 PID: 0 at fs/buffer.c:1235 __brelse fs/buffer.c:1235 [inline]
WARNING: CPU: 0 PID: 0 at fs/buffer.c:1235 __brelse+0x6d/0xb0 fs/buffer.c:1229
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.9.0-rc3-syzkaller-00208-g586b5dfb51b9 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__brelse fs/buffer.c:1235 [inline]
RIP: 0010:__brelse+0x6d/0xb0 fs/buffer.c:1229
Code: 84 d2 75 52 44 8b 63 60 31 ff 44 89 e6 e8 9b 95 81 ff 45 85 e4 75 20 e8 b1 9a 81 ff 90 48 c7 c7 e0 17 1e 8b e8 f4 6e 44 ff 90 <0f> 0b 90 90 5b 5d 41 5c e9 96 9a 81 ff e8 91 9a 81 ff be 04 00 00
RSP: 0018:ffffc90000007f40 EFLAGS: 00010082
RAX: 0000000000000000 RBX: ffff88806081c570 RCX: ffffffff81512be9
RDX: ffffffff8d495740 RSI: ffffffff81512bf6 RDI: 0000000000000001
RBP: ffff88806081c5d0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88806081c570 R14: dffffc0000000000 R15: ffffffff820cbbb0
FS:  0000000000000000(0000) GS:ffff88802c200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000030f21000 CR3: 00000000475c0000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 brelse include/linux/buffer_head.h:309 [inline]
 __invalidate_bh_lrus fs/buffer.c:1487 [inline]
 invalidate_bh_lru+0xa2/0x190 fs/buffer.c:1500
 csd_do_func kernel/smp.c:133 [inline]
 __flush_smp_call_function_queue+0x27a/0x8c0 kernel/smp.c:511
 __sysvec_call_function+0x8c/0x410 arch/x86/kernel/smp.c:262
 instr_sysvec_call_function arch/x86/kernel/smp.c:257 [inline]
 sysvec_call_function+0x90/0xb0 arch/x86/kernel/smp.c:257
 </IRQ>
 <TASK>
 asm_sysvec_call_function+0x1a/0x20 arch/x86/include/asm/idtentry.h:710
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline]
RIP: 0010:default_idle+0xf/0x20 arch/x86/kernel/process.c:743
Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d f3 e1 34 00 fb f4 <fa> c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
RSP: 0018:ffffffff8d407e20 EFLAGS: 00000246
RAX: 00000000000e0287 RBX: 0000000000000000 RCX: ffffffff8ad19b39
RDX: 0000000000000000 RSI: ffffffff8b0cb8e0 RDI: ffffffff8b6f0c20
RBP: fffffbfff1a92ae8 R08: 0000000000000001 R09: ffffed1005846fdd
R10: ffff88802c237eeb R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff8d495740 R14: ffffffff8f9d5890 R15: 0000000000000000
 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x32c/0x3f0 kernel/sched/idle.c:332
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
 rest_init+0x16b/0x2b0 init/main.c:737
 start_kernel+0x3a3/0x490 init/main.c:1079
 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
 common_startup_64+0x13e/0x148
 </TASK>
----------------
Code disassembly (best guess):
   0:	4c 01 c7             	add    %r8,%rdi
   3:	4c 29 c2             	sub    %r8,%rdx
   6:	e9 72 ff ff ff       	jmp    0xffffff7d
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	f3 0f 1e fa          	endbr64
  1f:	66 90                	xchg   %ax,%ax
  21:	0f 00 2d f3 e1 34 00 	verw   0x34e1f3(%rip)        # 0x34e21b
  28:	fb                   	sti
  29:	f4                   	hlt
* 2a:	fa                   	cli <-- trapping instruction
  2b:	c3                   	ret
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  2f:	cc                   	int3
  30:	66 66 2e 0f 1f 84 00 	data16 cs nopw 0x0(%rax,%rax,1)
  37:	00 00 00 00
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop