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 X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 442E8C433DF for ; Mon, 22 Jun 2020 06:42:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2420925424 for ; Mon, 22 Jun 2020 06:42:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="EyF5FuUs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726718AbgFVGm0 (ORCPT ); Mon, 22 Jun 2020 02:42:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41202 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726712AbgFVGm0 (ORCPT ); Mon, 22 Jun 2020 02:42:26 -0400 Received: from mail-qt1-x841.google.com (mail-qt1-x841.google.com [IPv6:2607:f8b0:4864:20::841]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E094DC061796 for ; Sun, 21 Jun 2020 23:42:25 -0700 (PDT) Received: by mail-qt1-x841.google.com with SMTP id g13so1499093qtv.8 for ; Sun, 21 Jun 2020 23:42:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=UhciZLVdGKEJk7KHTw+RU8JWs5dQKAECyz5UjSzBrP0=; b=EyF5FuUsWQitHjx7BN4lfK2XcWY7vlK1Elm2C5+czbIrJnmhqFTAkpW5dNchOjMYQa m2TLVe5resLpBBx6d16MAKG8YbkEM7gSyEr0VRWn6GoH7+uEoEW090OfViix7wAoT/6E vP8jz4YaO+TAiSfGRcxcZLnf94KukhpdZugyRYd9Cr/xOsWN93pQOg4ZrSpwwQPypW3y Xc/FL4aARuZ3E6Aoh8B/DXUBsDQxJ6n0Ey9MzbMssaMalGxbbiW+y4MMWDiQ8/y80Mhj SOLke1Gc4AIHcB/xAxa07KjuW2Gin3VRjJaRkMucEqOZeq60mtVn2HfRwq97kVDrfsgb jZ7Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=UhciZLVdGKEJk7KHTw+RU8JWs5dQKAECyz5UjSzBrP0=; b=D0iebjPyvMiGoMcQwmNodwQL1x1mHm2LaMMOz/fWcrnbMmlCGAbw7e0NCDXtj1VgBX 5TuXFjb66Cl+Lz2dIS/kRg+O8FsOYfCRwd4xIRlGazAG34qUiKsyffWNGywVelbXz+qS UFEcYuMV77uqfXhzkun/OmzBalKFR/BFDqyTSxxHLkO/du6DgXKKXpv6HokwRqSs4lp4 BCfCesvzser/2Wo/nInFZHBfcsBiRsT8cGaQJy6QQbqmoLD+OK83fxaGAviGrCozF6yx oZKkNsN7JjUYUznwSb0CV+w+l9vwRAXQUvqTHznFFGW1J3ZYbzfLBqiK4HOa0VnDTymn c0rA== X-Gm-Message-State: AOAM533ovW+Gh8KHGxKwaa/FmT0xwkx4aMmAO+N5sek2G9wCogWwKtKe gouODfp8TWpq9/rnE6cgGWr+v9OuTm1De5/cU33Siw== X-Google-Smtp-Source: ABdhPJxrXaR2MRdiPAJU6NZZSqPOj09boIx0YXa64M3CfHeEi2VvHVT8MYtt4nmImQOknEhCv3I16YGiBoKqk30+teY= X-Received: by 2002:ac8:36c2:: with SMTP id b2mr15006149qtc.257.1592808144668; Sun, 21 Jun 2020 23:42:24 -0700 (PDT) MIME-Version: 1.0 References: <000000000000617f9d05a8a5a2c4@google.com> <4A35E92B-9DEF-4833-81DD-0C6FA50EB174@lca.pw> In-Reply-To: <4A35E92B-9DEF-4833-81DD-0C6FA50EB174@lca.pw> From: Dmitry Vyukov Date: Mon, 22 Jun 2020 08:42:13 +0200 Message-ID: Subject: Re: linux-next boot error: WARNING in kmem_cache_free To: Qian Cai Cc: syzbot , linux-fsdevel , LKML , Linux-Next Mailing List , Stephen Rothwell , syzkaller-bugs , Al Viro Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-next-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-next@vger.kernel.org On Mon, Jun 22, 2020 at 8:29 AM Qian Cai wrote: > > On Jun 22, 2020, at 1:37 AM, syzbot wrote: > > > > WARNING: CPU: 0 PID: 0 at mm/slab.h:232 kmem_cache_free+0x0/0x200 mm/sl= ab.c:2262 > > Is there any particular reason to use CONFIG_SLAB rather than CONFIG_SLUB= ? There is a reason, it's still important for us. But also it's not our strategy to deal with bugs by not testing configurations and closing eyes on bugs, right? If it's an official config in the kernel, it needs to be tested. If SLAB is in the state that we don't care about any bugs in it, then we need to drop it. It will automatically remove it from all testing systems out there. Or at least make it "depends on BROKEN" to slowly phase it out during several releases. > You are really asking for trouble to test something that almost nobody is= exercising that code path very well nowadays. > > Anyway, there is a patchset in -mm that might well introduce this regress= ion that we could go to confirm it, but I kind of don=E2=80=99t want to spe= nd too much time on SLAB that suppose to be obsolete eventually.