From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f79.google.com (mail-ot1-f79.google.com [209.85.210.79]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3A310346E40 for ; Fri, 19 Dec 2025 15:15:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.79 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766157336; cv=none; b=n/TLwHhHXMI6j/qBtGjf80MIuMSPB/Vnj9WoXhOUZlCaGObggOuwoq4TWsf5WBuvm20homLFPQ+zlIfDl8dp/171izg1VQ4OoWFZ9zu/zg9IHL2rketFWM4B32n2+kNq6aT9APfhzKgYdw8VCO3giqL657WVrxr5RPU2SeF34bo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766157336; c=relaxed/simple; bh=NpVeFPFpv1R4L9PnXHfMZPEoK7JZWYzlyOrmCHncVsQ=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=OXnWufVatygb7j85gq7axsw/mfUiuYCv3D9ZWnHVJip1YsBKll8TWITBkoTNkEbcmQvauzdGRfkanGI+NaGIHt3+kKTgAztIlTR7LJwxXBfByO3t+nyRp3GvvvwVHSoSpA42BABhhi+ItJ8Dco95cfDEebkngmGFKSdMr6oQeKU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.210.79 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-ot1-f79.google.com with SMTP id 46e09a7af769-7c7599be25cso3489519a34.2 for ; Fri, 19 Dec 2025 07:15:32 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1766157332; x=1766762132; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=ZrLXi5yFv0qYWcnJNp69lP7G3qb5LjucnWTiIeW8S9Q=; b=GDZ3t+WL4Q+6we48BZCeEU93Oi+ARhulASiEsobFzyEQ9KG8S6MzZiBA5Ilm17aRf2 hKDmK2Oxl9adFqGp7LtfOc1gk8fRmN6vsN77rCc8CMvJgN4tPKjWnyK1lBnm5s3bu7nX pT1r4rdCjdVLuaOvXon6GutcRZ37Y7QL6pr99aoH841tzfcF2x6gRFBdiyKUwpdgrDes KxbiE/I+0lPd/hR4Bz7C09jvd0XWzlLjDlETwLCwp7qpVTPfmrppxTar+ciswn3aHiWl QuG15P3uCyDuXn3jMoKeZnPUpbaEoz7Brq3AjdYtDlyUtdvIHk7taNMrwMrkc5RoP/kD 1YSQ== X-Forwarded-Encrypted: i=1; AJvYcCV7DA6s+hkoT/nSXjhQw92Ba1XPC/8D6PCd5jrhDOyREn2TbwDXTx22WnmQlvG1glX/lLXOUD1SAW0acA4=@vger.kernel.org X-Gm-Message-State: AOJu0YxZxbZ75eWSDllBAG9/m5t1Q1r8udihnNE8h/J/9dtVWJgGEiDL iDMN9aPH6dszLQKS7CcS1EnmU3qx5YwPiXlzUjJJ4RU6dZ1VNaEjDhp5Z1Wp6lHVw6llnpznPQB 0DMWSKPFHsCxzd0KOoEVADA8gonqrSPXkpHtdbujKlGVreIpdFD0ay4Ojw7A= X-Google-Smtp-Source: AGHT+IGo1p/eAOFq2gEg6L7vcl5bVFW/wX9QM04M4QuMiVtQUVMFgRZE3Pa57iTjNPK2XquQ4wXDw3yAEkjc2YOlIsCW7rfP5ajJ Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:f028:b0:65d:579:95d9 with SMTP id 006d021491bc7-65d0ea9bdf3mr1468400eaf.41.1766157332172; Fri, 19 Dec 2025 07:15:32 -0800 (PST) Date: Fri, 19 Dec 2025 07:15:32 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69456c14.a70a0220.207337.0115.GAE@google.com> Subject: [syzbot] [mm?] INFO: rcu detected stall in sys_io_uring_enter (3) From: syzbot To: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 8ffd015db85f Linux 6.15-rc2 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=137b4fe4580000 kernel config: https://syzkaller.appspot.com/x/.config?x=a972ee73c2fcf8ca dashboard link: https://syzkaller.appspot.com/bug?extid=a62ea1d07ee6ab5ec277 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/2640fd4fd0f2/disk-8ffd015d.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/1c5931df89bc/vmlinux-8ffd015d.xz kernel image: https://storage.googleapis.com/syzbot-assets/f8fece45017d/bzImage-8ffd015d.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a62ea1d07ee6ab5ec277@syzkaller.appspotmail.com bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6067/1:b..l rcu: (detected by 1, t=10503 jiffies, g=10825, q=1601 ncpus=2) task:syz.0.44 state:R running task stack:22760 pid:6067 tgid:6065 ppid:5852 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b88/0x5240 kernel/sched/core.c:6767 preempt_schedule_irq+0xfe/0x1c0 kernel/sched/core.c:7090 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x167/0x2f0 arch/x86/include/asm/irqflags.h:-1 Code: c7 44 24 10 00 00 00 00 9c 8f 44 24 10 f7 44 24 10 00 02 00 00 0f 85 fd 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 65 48 8b 45 00 <48> 3b 44 24 38 0f 85 72 01 00 00 48 83 c4 40 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000b6ef1e8 EFLAGS: 00000206 RAX: 85be2b162476f200 RBX: ffffffff8ed3dfa0 RCX: 85be2b162476f200 RDX: 0000000000000000 RSI: ffffffff8e4fde18 RDI: ffffffff8ca1b520 RBP: ffffffff9368d020 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000002 R14: 0000000000000246 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd5/0x23b0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11e/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x11a/0x1d0 kernel/stacktrace.c:122 save_stack+0xfc/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x76/0x1e0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xde8/0x10a0 mm/page_alloc.c:2680 discard_slab mm/slub.c:2720 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3189 put_cpu_partial+0x17e/0x250 mm/slub.c:3264 __slab_free+0x294/0x390 mm/slub.c:4516 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4151 [inline] kmem_cache_alloc_bulk_noprof+0x4fe/0x7c0 mm/slub.c:5375 __io_alloc_req_refill+0xa3/0x330 io_uring/io_uring.c:963 io_alloc_req io_uring/io_uring.h:450 [inline] io_submit_sqes+0xc47/0x1ce0 io_uring/io_uring.c:2331 __do_sys_io_uring_enter io_uring/io_uring.c:3402 [inline] __se_sys_io_uring_enter+0x2cd/0x3560 io_uring/io_uring.c:3336 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f744438d169 RSP: 002b:00007f74451ef038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007f74445a6080 RCX: 00007f744438d169 RDX: 0000000000000000 RSI: 00000000000047f6 RDI: 0000000000000008 RBP: 00007f744440e990 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f74445a6080 R15: 00007f74446cfa28 bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) --- 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@googlegroups.com. 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 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