From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A326AC4167B for ; Sun, 26 Nov 2023 06:50:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229965AbjKZGue (ORCPT ); Sun, 26 Nov 2023 01:50:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56032 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229447AbjKZGua (ORCPT ); Sun, 26 Nov 2023 01:50:30 -0500 Received: from mail-pl1-f198.google.com (mail-pl1-f198.google.com [209.85.214.198]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 59A1AE5 for ; Sat, 25 Nov 2023 22:50:36 -0800 (PST) Received: by mail-pl1-f198.google.com with SMTP id d9443c01a7336-1cf7ff75820so37902395ad.1 for ; Sat, 25 Nov 2023 22:50:36 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700981436; x=1701586236; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=T/idrKmcOZ292i/teLtEPWoIY9+Yqi8viZCQk5eW5Pk=; b=M9NJwKt4yfMaT1eMTvLRxDjGYnqOCAeItssV6KsbGVFFKxGfVuUuaeYhEhDks9B2L+ SMdP/pf4Z63MjJA/+2TulLVM1GJodvxddfei6orIIUbk8NLztysJJDT+gSNGQ2lRxQq7 zzI5VxQpYbsKwPGmnpHHSom/vtDUAccXy1CPWjHeH075iU7+1PNjlE0euq8BTrCtAziG vBOl1OYexe1RN5KN8QibXXFZHWD/lqJ/ek8Via/U09ckAcT7xZhKj7IubZHCYYe3ju31 NtqHItr0eOfk9hMOo1/VeQgqca0gltJrwtsQVPqbScM0QhvpZ9JAbncUIJhOj1M3+0f5 aqVQ== X-Gm-Message-State: AOJu0YzjeGELxWNxY53wIRNYD/blMAxC2Nm2Yq1smr53XX6PrnjisHi+ gROvyn4v6O3btfqFH2LburKJfNimbaIwCS3QowBvHfod9PqzsPI= X-Google-Smtp-Source: AGHT+IEyk/ISFNEPopaSJLLIP24seorBy951tavxWN2PA5hIfLGCb2/pCdsWCrEh7/agNQPIF3m7YMBG3WzKmhSG84SZW4gSOtzS MIME-Version: 1.0 X-Received: by 2002:a17:902:d2d2:b0:1cf:9a43:d323 with SMTP id n18-20020a170902d2d200b001cf9a43d323mr1838939plc.11.1700981435983; Sat, 25 Nov 2023 22:50:35 -0800 (PST) Date: Sat, 25 Nov 2023 22:50:35 -0800 In-Reply-To: <000000000000f2771905a46374fe@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000042ee27060b089aff@google.com> Subject: Re: [syzbot] [net?] possible deadlock in sch_direct_xmit From: syzbot To: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org For archival purposes, forwarding an incoming command email to linux-kernel@vger.kernel.org. *** Subject: [net?] possible deadlock in sch_direct_xmit Author: eadavis@qq.com please test deadlock in sch_direct_xmit #syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 4195a4bc26ca..4605314e605e 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -338,8 +338,11 @@ bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, if (likely(skb)) { HARD_TX_LOCK(dev, txq, smp_processor_id()); - if (!netif_xmit_frozen_or_stopped(txq)) + if (!netif_xmit_frozen_or_stopped(txq)) { + netif_tx_stop_queue(txq); skb = dev_hard_start_xmit(skb, dev, txq, &ret); + netif_tx_start_queue(txq); + } else qdisc_maybe_clear_missed(q, txq);