From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AA5072063DB for ; Tue, 4 Feb 2025 20:09:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738699744; cv=none; b=E1wMpQHXZ5X+lTsltfv+HCRI1M44Rookm4DqZKfPfuOQVwjAmxsyfxPM8YJ7Xx2MTU8/hhcosqn2f9SHLhlQjHwL4IMoxaKe9XAtLKui0CS4vE6HN2dvPxdPez0Cq2dnTx+JufJ+tQc9ixvWxja88ZDSwpehSKw5bC31hFCj7ss= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738699744; c=relaxed/simple; bh=j8WMMwH8T5XWzuLoFTNF44Zl9T2jicDXJwYmEbB86Xw=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ZvQIekZZhGsIQfCgWSlTg/oXSdwt2uAUTtP8n6OTBCLAidoYqTvUWIGip09CG3qvlGJa14Jm/uE9MZl48uVc2ipcNf/+b3bksXDYdRCu1NPPw+QRdRxGVdf9hwsBoBpHDDsSQ22jz1bN5/rxgD/K9RBKDBfnndQSRFHe32HjpgA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SIB4SUiN; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="SIB4SUiN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 12DA8C4CEDF; Tue, 4 Feb 2025 20:09:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1738699744; bh=j8WMMwH8T5XWzuLoFTNF44Zl9T2jicDXJwYmEbB86Xw=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=SIB4SUiN3OlZR1QcxASA3hlTZEsdO+kjXCZRmFS/y7oWC2CeWxodXKHC7r/T8p2Sj GZAsOuj9qDuwMxB3B1rqZwziUO0jRDrb3rNp4Laoap+Iv45Ased0fSelhGo7YuBszc QAL4qxlVOO9vYbxAXujGHu6b/6Gb3dPz/nRasQqUzFirJYOK2B2zr/rdBzTBPIe3Co GuBfrP820IHbterN0NYmhPXIqAil2rC4GRj7wsTGoRSzhIcyMfekR+hAzjAFBnvUt5 zuPdL5IHuFcAEOXcF/r1QBSk19Uie/wi2rtV1qcG8XtWlVi41fbWJumCoerJusHjSp hbXYmRZy+vZDQ== Date: Tue, 4 Feb 2025 12:09:03 -0800 From: Jakub Kicinski To: Eric Dumazet Cc: "David S . Miller" , Paolo Abeni , netdev@vger.kernel.org, Kuniyuki Iwashima , Simon Horman , eric.dumazet@gmail.com Subject: Re: [PATCH v3 net 11/16] ipv6: input: convert to dev_net_rcu() Message-ID: <20250204120903.6c616fc8@kernel.org> In-Reply-To: <20250204132357.102354-12-edumazet@google.com> References: <20250204132357.102354-1-edumazet@google.com> <20250204132357.102354-12-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Tue, 4 Feb 2025 13:23:52 +0000 Eric Dumazet wrote: > @@ -488,7 +488,7 @@ static int ip6_input_finish(struct net *net, struct sock *sk, struct sk_buff *sk > int ip6_input(struct sk_buff *skb) > { > return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_IN, > - dev_net(skb->dev), NULL, skb, skb->dev, NULL, > + dev_net_rcu(skb->dev), NULL, skb, skb->dev, NULL, > ip6_input_finish); > } > EXPORT_SYMBOL_GPL(ip6_input); One more here: [ 4326.034939][ T50] ============================= [ 4326.035125][ T50] WARNING: suspicious RCU usage [ 4326.035299][ T50] 6.13.0-virtme #1 Not tainted [ 4326.035955][ T50] ----------------------------- [ 4326.036124][ T50] ./include/net/net_namespace.h:404 suspicious rcu_dereference_check() usage! [ 4326.036398][ T50] [ 4326.036398][ T50] other info that might help us debug this: [ 4326.036398][ T50] [ 4326.036684][ T50] [ 4326.036684][ T50] rcu_scheduler_active = 2, debug_locks = 1 [ 4326.036910][ T50] 2 locks held by kworker/2:1/50: [ 4326.037111][ T50] #0: ffff8880010a9548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7ec/0x16d0 [ 4326.037439][ T50] #1: ffffc9000036fd40 ((work_completion)(&trans->work)){+.+.}-{0:0}, at: process_one_work+0xe0b/0x16d0 [ 4326.037741][ T50] [ 4326.037741][ T50] stack backtrace: [ 4326.037930][ T50] CPU: 2 UID: 0 PID: 50 Comm: kworker/2:1 Not tainted 6.13.0-virtme #1 [ 4326.037935][ T50] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 4326.037937][ T50] Workqueue: events xfrm_trans_reinject [ 4326.037947][ T50] Call Trace: [ 4326.037949][ T50] [ 4326.037952][ T50] dump_stack_lvl+0xb0/0xd0 [ 4326.037963][ T50] lockdep_rcu_suspicious+0x1ea/0x280 [ 4326.037975][ T50] ip6_input+0x262/0x3e0 [ 4326.038009][ T50] xfrm_trans_reinject+0x2a2/0x460 [ 4326.038055][ T50] process_one_work+0xe55/0x16d0 [ 4326.038098][ T50] worker_thread+0x58c/0xce0 [ 4326.038121][ T50] kthread+0x359/0x5d0 [ 4326.038141][ T50] ret_from_fork+0x31/0x70 [ 4326.038150][ T50] ret_from_fork_asm+0x1a/0x30 Test output: https://netdev-3.bots.linux.dev/vmksft-net-dbg/results/978202/61-l2tp-sh/ Decoded: https://netdev-3.bots.linux.dev/vmksft-net-dbg/results/978202/vm-crash-thr2-0