Hello, syzbot found the following issue on: HEAD commit: 846bd2225ec3 Add linux-next specific files for 20250919 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=13c238e2580000 kernel config: https://syzkaller.appspot.com/x/.config?x=135377594f35b576 dashboard link: https://syzkaller.appspot.com/bug?extid=5c5d41e80248d610221f compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=155e427c580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17bb8142580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/c53d48022f8a/disk-846bd222.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/483534e784c8/vmlinux-846bd222.xz kernel image: https://storage.googleapis.com/syzbot-assets/721b36eec9b3/bzImage-846bd222.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+5c5d41e80248d610221f@xxxxxxxxxxxxxxxxxxxxxxxxx Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 0 UID: 0 PID: 5962 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: rcu_gp srcu_invoke_callbacks RIP: 0010:__list_del_entry_valid_or_report+0x25/0x190 lib/list_debug.c:49 Code: 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 41 55 41 54 53 48 89 fb 49 bd 00 00 00 00 00 fc ff df 48 83 c7 08 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 05 e8 af 58 47 fd 4c 8b 7b 08 48 89 d8 48 c1 e8 RSP: 0018:ffffc90003d2f8e8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffff88802f573c80 RDX: 0000000000000000 RSI: 0000000000000200 RDI: 0000000000000008 RBP: dffffc0000000000 R08: ffffffff8fe4db77 R09: 1ffffffff1fc9b6e R10: dffffc0000000000 R11: ffffffff84b089f0 R12: 1ffff11004cb1e1f R13: dffffc0000000000 R14: ffff88802658f0a0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881257a2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055946acdc950 CR3: 000000007a708000 CR4: 00000000003526f0 Call Trace: <TASK> __list_del_entry_valid include/linux/list.h:132 [inline] __list_del_entry include/linux/list.h:223 [inline] list_del_init include/linux/list.h:295 [inline] blk_mq_free_tags_callback+0x5a/0x180 block/blk-mq-tag.c:593 srcu_invoke_callbacks+0x208/0x450 kernel/rcu/srcutree.c:1807 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__list_del_entry_valid_or_report+0x25/0x190 lib/list_debug.c:49 Code: 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 41 55 41 54 53 48 89 fb 49 bd 00 00 00 00 00 fc ff df 48 83 c7 08 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 05 e8 af 58 47 fd 4c 8b 7b 08 48 89 d8 48 c1 e8 RSP: 0018:ffffc90003d2f8e8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffff88802f573c80 RDX: 0000000000000000 RSI: 0000000000000200 RDI: 0000000000000008 RBP: dffffc0000000000 R08: ffffffff8fe4db77 R09: 1ffffffff1fc9b6e R10: dffffc0000000000 R11: ffffffff84b089f0 R12: 1ffff11004cb1e1f R13: dffffc0000000000 R14: ffff88802658f0a0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881257a2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055946acdc950 CR3: 000000007a708000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: f3 0f 1e fa endbr64 9: 41 57 push %r15 b: 41 56 push %r14 d: 41 55 push %r13 f: 41 54 push %r12 11: 53 push %rbx 12: 48 89 fb mov %rdi,%rbx 15: 49 bd 00 00 00 00 00 movabs $0xdffffc0000000000,%r13 1c: fc ff df 1f: 48 83 c7 08 add $0x8,%rdi 23: 48 89 f8 mov %rdi,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2f: 74 05 je 0x36 31: e8 af 58 47 fd call 0xfd4758e5 36: 4c 8b 7b 08 mov 0x8(%rbx),%r15 3a: 48 89 d8 mov %rbx,%rax 3d: 48 rex.W 3e: c1 .byte 0xc1 3f: e8 .byte 0xe8 --- This report is generated by a bot. 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