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 CE1CAC433E0 for ; Mon, 28 Dec 2020 18:22:35 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3CF352242A for ; Mon, 28 Dec 2020 18:22:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3CF352242A 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 6E4888D0016; Mon, 28 Dec 2020 13:22:34 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 6960B8D0010; Mon, 28 Dec 2020 13:22:34 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 50CF58D0017; Mon, 28 Dec 2020 13:22:34 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0201.hostedemail.com [216.40.44.201]) by kanga.kvack.org (Postfix) with ESMTP id 392B48D0016 for ; Mon, 28 Dec 2020 13:22:34 -0500 (EST) Received: from smtpin04.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id EC7F91EF1 for ; Mon, 28 Dec 2020 18:22:33 +0000 (UTC) X-FDA: 77643511386.04.test32_5c03d4d27495 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin04.hostedemail.com (Postfix) with ESMTP id BF388800504F for ; Mon, 28 Dec 2020 18:22:33 +0000 (UTC) X-HE-Tag: test32_5c03d4d27495 X-Filterd-Recvd-Size: 3912 Received: from mail-ej1-f47.google.com (mail-ej1-f47.google.com [209.85.218.47]) by imf17.hostedemail.com (Postfix) with ESMTP for ; Mon, 28 Dec 2020 18:22:33 +0000 (UTC) Received: by mail-ej1-f47.google.com with SMTP id ga15so15261546ejb.4 for ; Mon, 28 Dec 2020 10:22:33 -0800 (PST) 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=z2QbH8RGPNV6UCpysofOcmKw2kvcdsWtyhs8XyCCINw=; b=oK1bIMFlk9+9P3yM6IxgC3sGgIIGBKSSzhxKjcmUmJw7zLxWGUG5Z4FT5RjgRhaBPN i7pYF9MtjhuJl7YWB8Sew1jRxwXZSpYdf7aochu1zb+ZWaH/fiz/eL4vSeZrajQE63Mv z8yRPyof9nFuCxMdTOpQKJbsFriOk4ifql5kOVecC6wXCqfH3/TJiCf5HKOIcx3H/IHz eIH4ub0+o/wzo0oEQ22VsKGEYwpVGASXaadXI+DYrBGeTAtjrCS7Bn2U/ZMS4ZMjCFOD I+9SQ2avnuepdBFUxQ4VZoQZyuyE/I1RxB1mpVZUmeo/uUA5VcVuLaaClMMSXkvR+40v RCrA== 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=z2QbH8RGPNV6UCpysofOcmKw2kvcdsWtyhs8XyCCINw=; b=Nu4wYrVf80j2K54kt/7oBHu4SFqN6lTF7pu0/n/nGN9lQstFo+JUgiXYrYB86j+yAv cZimf1V1nFM5BbumCXDsb33jT3bFrutod+oD7i0xaTyJTIvLh+d2OF/Ulh6WtHJHqod5 xnpa3hce92JffvTrpuYo7RFR8O1rL6NiF0bJa4WhPNxHU/uwv+q5jdl9fVBsu7UT9QCR DK+aHDFnFN+LMvB1+1tbU/gSkr4wP/iUUYl37ovb3Km5OWZzTmi5vI4/e+j68AVN7+by lcAGXCdWRMMSe468pRFuLOPsE4UCC+6l1uTGJqimw+Z38Fljs6GBtE9Xn3YC1VvQi1Qt 4ICQ== X-Gm-Message-State: AOAM532E1ag1uBAMWhmngpOzh/DBrXmmpJNNfdQc+wB79Y7mDgjdMgNK F+2tXblgG1Fkwo2wUzKFTQyqrFnLIixRWLj5iLyoZQ== X-Google-Smtp-Source: ABdhPJwvPxy4pkRK8okJN0/k8NDFvWE5wVUKTWXkCWpjS8Ii2ZVkfms8OJy9V0jmRbDe+48+k7MFRRK2mCrz0IR2NF4= X-Received: by 2002:a17:906:447:: with SMTP id e7mr42157038eja.172.1609179752023; Mon, 28 Dec 2020 10:22:32 -0800 (PST) MIME-Version: 1.0 References: <20201013013416.390574-1-dima@arista.com> <20201013013416.390574-3-dima@arista.com> In-Reply-To: <20201013013416.390574-3-dima@arista.com> From: Brian Geffon Date: Mon, 28 Dec 2020 10:21:56 -0800 Message-ID: Subject: Re: [PATCH 2/6] mm/mremap: For MREMAP_DONTUNMAP check security_vm_enough_memory_mm() To: Dmitry Safonov Cc: LKML , Dmitry Safonov <0x7f454c46@gmail.com>, Alexander Viro , Andrew Morton , Andy Lutomirski , Catalin Marinas , Dan Williams , Dave Jiang , Hugh Dickins , Ingo Molnar , "Kirill A. Shutemov" , Mike Kravetz , Minchan Kim , Russell King , Thomas Bogendoerfer , Thomas Gleixner , Vishal Verma , Vlastimil Babka , Will Deacon , linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, linux-mm Content-Type: text/plain; charset="UTF-8" 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: This looks good to me with a small comment. > if (do_munmap(mm, old_addr, old_len, uf_unmap) < 0) { > /* OOM: unable to split vma, just get accounts right */ > - if (vm_flags & VM_ACCOUNT) > + if (vm_flags & VM_ACCOUNT && !(flags & MREMAP_DONTUNMAP)) > vm_acct_memory(new_len >> PAGE_SHIFT); Checking MREMAP_DONTUNMAP in the do_munmap path is unnecessary as MREMAP_DONTUNMAP will have already returned by this point.