------------[ cut here ]------------ VFS: brelse: Trying to free free buffer WARNING: CPU: 1 PID: 52 at fs/buffer.c:1145 __brelse fs/buffer.c:1145 [inline] WARNING: CPU: 1 PID: 52 at fs/buffer.c:1145 brelse include/linux/buffer_head.h:326 [inline] WARNING: CPU: 1 PID: 52 at fs/buffer.c:1145 __invalidate_bh_lrus fs/buffer.c:1380 [inline] WARNING: CPU: 1 PID: 52 at fs/buffer.c:1145 invalidate_bh_lru+0xf8/0x1a0 fs/buffer.c:1393 Modules linked in: CPU: 1 PID: 52 Comm: kworker/1:1H Not tainted 6.1.127-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events_highpri snd_vmidi_output_work RIP: 0010:__brelse fs/buffer.c:1145 [inline] RIP: 0010:brelse include/linux/buffer_head.h:326 [inline] RIP: 0010:__invalidate_bh_lrus fs/buffer.c:1380 [inline] RIP: 0010:invalidate_bh_lru+0xf8/0x1a0 fs/buffer.c:1393 Code: 00 e8 dc 8d e0 ff f0 ff 0b eb 21 e8 42 f9 88 ff 41 80 3c 2e 00 75 26 eb 2c e8 34 f9 88 ff 48 c7 c7 e0 11 1a 8b e8 48 12 51 ff <0f> 0b 48 bd 00 00 00 00 00 fc ff df 41 80 3c 2e 00 74 08 4c 89 ff RSP: 0018:ffffc900001e0f38 EFLAGS: 00010046 RAX: 0054aa9477b42c00 RBX: ffff88804ccdf060 RCX: ffff8880206d3b80 RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff8152b84e R09: fffff5200003c149 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b8f368f8 R13: 0000000000000000 R14: 1ffff110171e6d1f R15: ffff8880b8f368f8 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000202d2000 CR3: 000000005947f000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __flush_smp_call_function_queue+0x2d9/0xd00 kernel/smp.c:641 __sysvec_call_function_single+0xbb/0x360 arch/x86/kernel/smp.c:267 instr_sysvec_call_function_single arch/x86/kernel/smp.c:262 [inline] sysvec_call_function_single+0x98/0xc0 arch/x86/kernel/smp.c:262 asm_sysvec_call_function_single+0x16/0x20 arch/x86/include/asm/idtentry.h:699 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 02 f0 24 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 f7 4f a1 f6 65 8b 05 98 2f 45 75 85 c0 74 3f 48 c7 04 24 0e 36 RSP: 0018:ffffc90000bd7a40 EFLAGS: 00000206 RAX: 0054aa9477b42c00 RBX: 1ffff9200017af4c RCX: ffffffff816b127a RDX: dffffc0000000000 RSI: ffffffff8b0c0340 RDI: 0000000000000001 RBP: ffffc90000bd7ad0 R08: dffffc0000000000 R09: fffffbfff224a06d R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff9200017af48 R14: ffffc90000bd7a60 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] snd_rawmidi_transmit+0x33a/0x3f0 sound/core/rawmidi.c:1478 snd_vmidi_output_work+0x1dd/0x460 sound/core/seq/seq_virmidi.c:151 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 9c pushf 1: 8f 44 24 20 pop 0x20(%rsp) 5: 42 80 3c 23 00 cmpb $0x0,(%rbx,%r12,1) a: 74 08 je 0x14 c: 4c 89 f7 mov %r14,%rdi f: e8 02 f0 24 f7 call 0xf724f016 14: f6 44 24 21 02 testb $0x2,0x21(%rsp) 19: 75 4e jne 0x69 1b: 41 f7 c7 00 02 00 00 test $0x200,%r15d 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 f7 4f a1 f6 call 0xf6a15026 <-- trapping instruction 2f: 65 8b 05 98 2f 45 75 mov %gs:0x75452f98(%rip),%eax # 0x75452fce 36: 85 c0 test %eax,%eax 38: 74 3f je 0x79 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss