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=-13.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 83524C2B9F4 for ; Tue, 15 Jun 2021 02:46:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 57128613C2 for ; Tue, 15 Jun 2021 02:46:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230188AbhFOCse (ORCPT ); Mon, 14 Jun 2021 22:48:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48774 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229609AbhFOCs3 (ORCPT ); Mon, 14 Jun 2021 22:48:29 -0400 Received: from mail-ej1-x633.google.com (mail-ej1-x633.google.com [IPv6:2a00:1450:4864:20::633]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C2892C061574 for ; Mon, 14 Jun 2021 19:46:24 -0700 (PDT) Received: by mail-ej1-x633.google.com with SMTP id gt18so1377291ejc.11 for ; Mon, 14 Jun 2021 19:46:24 -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; bh=vVu/q50mLKZC8+FmqE6RzI+X9/hmuWYOAB854u4sNe0=; b=lH8grbcFhCAO4tnhWvsAdMiBjS0dTx3HutQQBO9coicIiuYTgrOeRLwpRjHXqMce1/ jlap8x9hVMfojCAQL0TmYXz+FyLqz+bqKIlRSJS3e+s2DHZplVtmv0r7hBkVZzC2o+er nxlHTtAb3r4mchIxkgI5MOGYLAzko3i2pecmOL0Z42EF0b3ox+/Pmr1dSd7003L0FrDr aoAuPuvRiIIuj+kiBzu5zJQcJDus9CmYTMuIB9AyBdYK4OnA7adx7M6L4FlbGfyhjdmq I8QALrFxn/N9hR0DJ6Xv8/n4+4+0/0zRI6bM7liU6yRbMP0oPJL0Pt48DtbAVjrqTH/u BxVg== 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; bh=vVu/q50mLKZC8+FmqE6RzI+X9/hmuWYOAB854u4sNe0=; b=MWlssjUwyrX1417TslAeDnVWZXx2AkPHF0fgcjBx9x4FEHwY6EjfMJzDGU9cWme/+R k7RoXE8Zahj9YkwuMjZ9ono+1M0iafmG6R7+Sjc4nJez7q+Tif7KulkcT13oSV87bTDF vZRbtq1JaEyIFuyOV+sKuiN5zT7EfG6v68Ou7IoRagKiB7yXhUwpV80vVBNVGujMlZu8 aCrB255pqCw/wCbOqbucoiM7o+fEdx05ZCiiHK9qQSdLqQBsOJLkQAKBTFV7jSaJ62AA 8MxVroZJTWrxWwWgvLps7Rv+eQFHjBolHA3BC30MkOHXCr005nA1qMtRsgbceuw0R71k 5REA== X-Gm-Message-State: AOAM533MZRRdIEE6mRMwY0PEftv/AlekNfPQMGjQRwpMJYIFHdFEWJyE mAgiEmqTxfVGw5+7lkOI/vRQE0d/CF4EpuVV9YZ3NYojMlx0gQ== X-Google-Smtp-Source: ABdhPJxZ/dgSfmoQFiza4iMe8qVVuP8sYLGcxHmV82OdFool6B9csSY6OkHOGeXlUVIIywTaOOGzKuIwejrZQ+CsBo0= X-Received: by 2002:a05:6512:1144:: with SMTP id m4mr14563109lfg.390.1623724714373; Mon, 14 Jun 2021 19:38:34 -0700 (PDT) MIME-Version: 1.0 References: <20210615012014.1100672-1-jannh@google.com> <20210614190032.09d8b7ac530c8b14ace44b82@linux-foundation.org> In-Reply-To: From: Jann Horn Date: Tue, 15 Jun 2021 04:38:08 +0200 Message-ID: Subject: Re: [PATCH v2] mm/gup: fix try_grab_compound_head() race with split_huge_page() To: Andrew Morton Cc: Linux-MM , kernel list , Matthew Wilcox , "Kirill A . Shutemov" , John Hubbard , Jan Kara , stable , Michal Hocko Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 15, 2021 at 4:36 AM Jann Horn wrote: > If you don't like the ifdeffery in this patch, can you please merge > the v1 patch? It's not like I was adding a new BUG_ON(), I was just > refactoring an existing BUG_ON() into a helper function, so I wasn't > making things worse; and I don't want to think about how to best > design WARN/BUG macros for the VM subsystem in order to land this > bugfix. Ah, nevermind, I hadn't seen that you already merged this one. 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=-13.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 9D51CC2B9F4 for ; Tue, 15 Jun 2021 02:38:37 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3E0F1613C2 for ; Tue, 15 Jun 2021 02:38:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3E0F1613C2 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D385B6B0036; Mon, 14 Jun 2021 22:38:36 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D07A26B006E; Mon, 14 Jun 2021 22:38:36 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BB0E86B0070; Mon, 14 Jun 2021 22:38:36 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0204.hostedemail.com [216.40.44.204]) by kanga.kvack.org (Postfix) with ESMTP id 8AC7B6B0036 for ; Mon, 14 Jun 2021 22:38:36 -0400 (EDT) Received: from smtpin34.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 291C38249980 for ; Tue, 15 Jun 2021 02:38:36 +0000 (UTC) X-FDA: 78254399832.34.960BB8C Received: from mail-lf1-f46.google.com (mail-lf1-f46.google.com [209.85.167.46]) by imf26.hostedemail.com (Postfix) with ESMTP id AE8D341449E4 for ; Tue, 15 Jun 2021 02:38:30 +0000 (UTC) Received: by mail-lf1-f46.google.com with SMTP id q20so9519842lfo.2 for ; Mon, 14 Jun 2021 19:38:35 -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; bh=vVu/q50mLKZC8+FmqE6RzI+X9/hmuWYOAB854u4sNe0=; b=lH8grbcFhCAO4tnhWvsAdMiBjS0dTx3HutQQBO9coicIiuYTgrOeRLwpRjHXqMce1/ jlap8x9hVMfojCAQL0TmYXz+FyLqz+bqKIlRSJS3e+s2DHZplVtmv0r7hBkVZzC2o+er nxlHTtAb3r4mchIxkgI5MOGYLAzko3i2pecmOL0Z42EF0b3ox+/Pmr1dSd7003L0FrDr aoAuPuvRiIIuj+kiBzu5zJQcJDus9CmYTMuIB9AyBdYK4OnA7adx7M6L4FlbGfyhjdmq I8QALrFxn/N9hR0DJ6Xv8/n4+4+0/0zRI6bM7liU6yRbMP0oPJL0Pt48DtbAVjrqTH/u BxVg== 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; bh=vVu/q50mLKZC8+FmqE6RzI+X9/hmuWYOAB854u4sNe0=; b=B2CNgfx0R+/B0tKRHjykwgQznIuGhzmaSNUeUF65O0HZ3nuH8ITYIOkY1DDoOhpD4D tAqLKFwQ4GyQ1LcH6EsBu4QbDE7UdrJJXnlsCqvgKVEuPOwJOYBUPT6W9nf7DwBUfH+d E7hiJoikb2eOggRgKjVS9QbbhIQBEaxUMVrOhIXVqvlD0w2hGNzooGyssyfna2qEfLQb uQNMLX1Oe2NS9eSIk69IivyptLMyS5ssB67gGbRoVafgRCt5F1Jfe2NV3z0kDKZrdqNJ 8k8YLSZNS1BJjd8cqokIYiPo2uz+2MYHjoNa+NcKETP3k2SK7ISzRoaUIhj8mw6ZxMHe R3PA== X-Gm-Message-State: AOAM53195FEZj66wIta37mcPP6QCmb7DqzZ9qqSQhvcG78iTtArkEOcB uDRAXGB+CpV+IK8ERDkfRV3svUilTO2gNE7VF++d2w== X-Google-Smtp-Source: ABdhPJxZ/dgSfmoQFiza4iMe8qVVuP8sYLGcxHmV82OdFool6B9csSY6OkHOGeXlUVIIywTaOOGzKuIwejrZQ+CsBo0= X-Received: by 2002:a05:6512:1144:: with SMTP id m4mr14563109lfg.390.1623724714373; Mon, 14 Jun 2021 19:38:34 -0700 (PDT) MIME-Version: 1.0 References: <20210615012014.1100672-1-jannh@google.com> <20210614190032.09d8b7ac530c8b14ace44b82@linux-foundation.org> In-Reply-To: From: Jann Horn Date: Tue, 15 Jun 2021 04:38:08 +0200 Message-ID: Subject: Re: [PATCH v2] mm/gup: fix try_grab_compound_head() race with split_huge_page() To: Andrew Morton Cc: Linux-MM , kernel list , Matthew Wilcox , "Kirill A . Shutemov" , John Hubbard , Jan Kara , stable , Michal Hocko Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: AE8D341449E4 Authentication-Results: imf26.hostedemail.com; dkim=pass header.d=google.com header.s=20161025 header.b=lH8grbcF; spf=pass (imf26.hostedemail.com: domain of jannh@google.com designates 209.85.167.46 as permitted sender) smtp.mailfrom=jannh@google.com; dmarc=pass (policy=reject) header.from=google.com X-Stat-Signature: zxhwyqw8ift5i3p4i5i9w1su1w8qgfj8 X-HE-Tag: 1623724710-724129 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Jun 15, 2021 at 4:36 AM Jann Horn wrote: > If you don't like the ifdeffery in this patch, can you please merge > the v1 patch? It's not like I was adding a new BUG_ON(), I was just > refactoring an existing BUG_ON() into a helper function, so I wasn't > making things worse; and I don't want to think about how to best > design WARN/BUG macros for the VM subsystem in order to land this > bugfix. Ah, nevermind, I hadn't seen that you already merged this one.