From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oa1-f71.google.com (mail-oa1-f71.google.com [209.85.160.71]) (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 1D16F2D9EFB for ; Mon, 21 Sep 2026 03:24:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.71 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789961056; cv=none; b=Y1POOW5ReGTDVBPk3DI3brO0s1i3S4YVLWNO58QF4JWsu9QlP3YL4pLHEYSRPHUahxJiXK7gFOutKHNbeK0HqvXW/m8lqUkUhUNU9avPL1D+F6HxSe1hG3YcqoKVTUOGcIbkD4I+7igj2ngWrhN7PZMtFG7qQHS53+chXPO0j2M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789961056; c=relaxed/simple; bh=Q/3/5Nx5FM48RTGX6txObAhBKRMQKcQXI809YkxxirY=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To:Cc: Content-Type; b=MTurBmuZm661AZPFM7r5ECTyKrHEywvcUQXBelXCoVUvl01s6Ph61XYAL2iYhN1IjOS6GoQE+kjfg+ST42vFD7rmN2G+49bDJwk9njB5IU3YA+IfMUvsmr+9Lbzt/pPdn7rvinkjgONQTX3+dahTWMLLmHNmXz9g+NRdA3Ez0b8= 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=209.85.160.71 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-oa1-f71.google.com with SMTP id 586e51a60fabf-4566537e644so4409732fac.0 for ; Sun, 20 Sep 2026 20:24:14 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1789961054; x=1790565854; h=content-type:cc:to:from:subject:message-id:in-reply-to:date :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to:content-type; bh=wJ3hMGw7iw6O9BkY5HoyPwy1BTyJgCiMk7aL5MnnWMw=; b=HJrbXtbIdE/j48HHsRvHS7T7azY6olFh0Xr9F2CpOme1dWMR9COSm463xUJmJOpTWA 1wd/mKgahensD7utGMrXtryv7XQavLmlotobyp9hhnVtUIe2rad4MyvOUSonolkLhBBP OiUxIoVmMPmwCE5UPH8wfYtkvaaPlXeLd/AqNteZ4bkNvCS0ZTSj6odkTVNs0X0qWkFz AcmNS+I8vnellkNSxihjYHjMI4kFMz+idf2BexNbl0ym8yTNDpKnbqOcLRFBOyjE+cNO CsN6C24ZYH9rsFhlyz65gdzR8JWGPkz8Gvse+dCYVyIRXTlx0angg1SmiWGq5+WnjuKL lqDg== X-Forwarded-Encrypted: i=1; AKwUvBxWo6h53kibCfwKliOIln9uMOK7y/BliOdwCNwgyX4HYb5qovm2IDLjDsHWnPashHQjXLps1JM=@vger.kernel.org X-Gm-Message-State: AFuF++lVxVoeREGUGbi1kmYd4FWHKv3mnCTovAUpZgotIfywX/VkTs3o 2CsC8svJ/HPVEp09x1EYzosLgpa5JXTTMysokcbKpPKdX4Gj/gGYbTkuFKyltV6/IRcMjG7IfTI lzkCVABoZvyTquy5meLFTD3PgdBsDzeKdOQ+fMOOh7TiNO0VJD17PU5rT0Lk= Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:4d0a:b0:6cd:3ffc:acfc with SMTP id 006d021491bc7-6cd3ffcef09mr6027448eaf.76.1789961053959; Sun, 20 Sep 2026 20:24:13 -0700 (PDT) Date: Sun, 20 Sep 2026 20:24:13 -0700 In-Reply-To: <20260918210419.4088201-1-kuba@kernel.org> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6ab0a35d.71f81b7d.15fa6d.001f.GAE@google.com> Subject: [syzbot ci] Re: net: opt loopback into instance locking From: syzbot ci To: andrew@lunn.ch, davem@davemloft.net, edumazet@google.com, horms@kernel.org, kuba@kernel.org, netdev@vger.kernel.org, pabeni@redhat.com Cc: syzbot@lists.linux.dev, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" syzbot ci has tested the following series [v1] net: opt loopback into instance locking https://lore.kernel.org/all/20260918210419.4088201-1-kuba@kernel.org * [PATCH net-next] net: opt loopback into instance locking and found the following issue: WARNING in ipv6_add_dev Full report is available here: https://ci.syzbot.org/series/f12bc892-cfa6-4277-beac-794482c9a3f7 *** WARNING in ipv6_add_dev tree: net-next URL: https://kernel.googlesource.com/pub/scm/linux/kernel/git/netdev/net-next.git base: 8830e65ed46de41f849eefb8ba227d4852c460f6 arch: amd64 compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 config: https://ci.syzbot.org/builds/ae142b5c-beb2-4c41-814c-2cd3e14bdbb0/config usbcore: registered new interface driver snd-usb-hiface usbcore: registered new interface driver snd-bcd2000 usbcore: registered new interface driver snd_usb_pod usbcore: registered new interface driver snd_usb_podhd usbcore: registered new interface driver snd_usb_toneport usbcore: registered new interface driver snd_usb_variax drop_monitor: Initializing network drop monitor service NET: Registered PF_LLC protocol family GACT probability on Mirror/redirect action on Simple TC action Loaded u32 classifier Performance counters on input device check on Actions configured nf_conntrack_irc: The irc conntrack helper is scheduled for removal. Please contact the netfilter-devel mailing list if you still need this. The pptp conntrack helper is scheduled for removal. Please contact the netfilter-devel mailing list if you still need this. The DCCP match is deprecated and scheduled to be removed in 2027. Please contact the netfilter-devel mailing list or update your iptables rules xt_time: kernel timezone is -0000 IPVS: Registered protocols (TCP, UDP, SCTP, AH, ESP) IPVS: Connection hash table configured (size=4096, memory=32Kbytes) IPVS: ipvs loaded. IPVS: [rr] scheduler registered. IPVS: [wrr] scheduler registered. IPVS: [lc] scheduler registered. IPVS: [wlc] scheduler registered. IPVS: [fo] scheduler registered. IPVS: [ovf] scheduler registered. IPVS: [lblc] scheduler registered. IPVS: [lblcr] scheduler registered. IPVS: [dh] scheduler registered. IPVS: [sh] scheduler registered. IPVS: [mh] scheduler registered. IPVS: [sed] scheduler registered. IPVS: [nq] scheduler registered. IPVS: [twos] scheduler registered. IPVS: [sip] pe registered. ipip: IPv4 and MPLS over IPv4 tunneling driver gre: GRE over IPv4 demultiplexer driver ip_gre: GRE over IPv4 tunneling driver IPv4 over IPsec tunneling driver Initializing XFRM netlink socket IPsec XFRM device driver xfrm_iptfs: IPsec IP-TFS tunnel mode module NET: Registered PF_INET6 protocol family ------------[ cut here ]------------ debug_locks && !(lock_is_held(&(&dev->lock)->dep_map) != 0) WARNING: ./include/net/netdev_lock.h:70 at ipv6_add_dev+0xfc1/0x1400, CPU#0: swapper/0/1 Modules linked in: CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:ipv6_add_dev+0xfc1/0x1400 Code: ff ff e8 a2 6e 3a f7 48 8d 3d 6b 56 fd 05 48 c7 c6 80 a2 32 8d ba 80 01 00 00 67 48 0f b9 3a e9 ab f0 ff ff e8 80 6e 3a f7 90 <0f> 0b 90 e9 cb f1 ff ff e8 72 6e 3a f7 48 8d 3d 5b 56 fd 05 48 c7 RSP: 0000:ffffc900000678c0 EFLAGS: 00010293 RAX: ffffffff8a8d6400 RBX: dffffc0000000000 RCX: ffff888102abda00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff90253707 R09: 1ffffffff204a6e0 R10: dffffc0000000000 R11: fffffbfff204a6e1 R12: dffffc0000000000 R13: ffff88810c036000 R14: ffffffff8caa6a10 R15: ffff88810c036008 FS: 0000000000000000(0000) GS:ffff88818d6cd000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff88823ffff000 CR3: 000000000eb48000 CR4: 00000000000006f0 Call Trace: addrconf_init+0x8b/0x170 inet6_init+0x228/0x3f0 do_one_initcall+0x250/0x870 do_initcall_level+0x10a/0x1a0 do_initcalls+0x59/0xa0 kernel_init_freeable+0x29d/0x3e0 kernel_init+0x22/0x1d0 ret_from_fork+0x514/0xb70 ret_from_fork_asm+0x1a/0x30 *** If these findings have caused you to resend the series or submit a separate fix, please add the following tag to your commit message: Tested-by: syzbot@syzkaller.appspotmail.com --- This report is generated by a bot. It may contain errors. syzbot ci engineers can be reached at syzkaller@googlegroups.com. To test a fix for this bug, please reply with `#syz test` (on a separate line) and attach the patch to the email. Notes: - The patch will be applied on top of the tested series (as an incremental fix). - To test a new version of the whole series, please send it directly to syzbot@lists.linux.dev. - Arguments like custom git repos and branches are not supported.