On 9/22/25 2:24 PM, syzbot wrote: > 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. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title > > If you want syzbot to run the reproducer, reply with: > #syz test: git://repo/address.git branch-or-commit-hash > If you attach or paste a git patch, syzbot will apply it before testing. > > If you want to overwrite report's subsystems, reply with: > #syz set subsystems: new-subsystem > (See the list of subsystem names on the web dashboard) > > If the report is a duplicate of another one, reply with: > #syz dup: exact-subject-of-another-report > > If you want to undo deduplication, reply with: > #syz undup Adding Ming, looks related to the SRCU changes perhaps? -- Jens Axboe
