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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id D02B7C433F5 for ; Thu, 10 Feb 2022 07:20:37 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 270A16B0071; Thu, 10 Feb 2022 02:20:37 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 221696B0074; Thu, 10 Feb 2022 02:20:37 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 110B46B0075; Thu, 10 Feb 2022 02:20:37 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0245.hostedemail.com [216.40.44.245]) by kanga.kvack.org (Postfix) with ESMTP id F2F6A6B0071 for ; Thu, 10 Feb 2022 02:20:36 -0500 (EST) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 8A18C972EA for ; Thu, 10 Feb 2022 07:20:36 +0000 (UTC) X-FDA: 79126022472.18.EA6D037 Received: from mail-yb1-f172.google.com (mail-yb1-f172.google.com [209.85.219.172]) by imf13.hostedemail.com (Postfix) with ESMTP id 4E13220004 for ; Thu, 10 Feb 2022 07:20:35 +0000 (UTC) Received: by mail-yb1-f172.google.com with SMTP id y129so12807680ybe.7 for ; Wed, 09 Feb 2022 23:20:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ZX/WOZsnGI7NHrW3LHW9fWbxuWWXkvq+KrfxlH19WkQ=; b=mnCQTtryb0tmtF8+f3k+sVI71drjg1mVtn46FiiiRafv0su+7dnP8kwTMp/ROdO048 fcfOjVYrES+pwRrCHDsb2EFqdXLRXvCOJUML8Byl50JsMjb2ZqqzRvyi27AFULX36V4k e0bSSMnAvdy+UuvKrjJF2Eq/gWCNzHStw1iY8Gd29DOd4pTEqiMb6E4B7Yc8wGmJ1dPg tK05dDTqrH0pimHGgGB5AoLlLnyIFeckKIV8XW2xPI+VISAKUXI633AEmu4XAbQfENd5 +CTvdOtmZZU5UzYXvyu94nambEXkpN3j2sx3dD7w9y9ciuqii1a6zZf1spDvyf1PlvZf h8dA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ZX/WOZsnGI7NHrW3LHW9fWbxuWWXkvq+KrfxlH19WkQ=; b=VM40qmcpL2qxuU3AkPR0Pzr1c8rk4qdTm9cWt1QH8VoZtq1GPqmlokl2j7G5lYycoV JUvbUt6zExSX2gfiyWbsiM8BPy/RVE6nl8adzYUxbRDzLF8NzYsHNs993ltZor+ibSTj PZpHmUvS/bOS5w4BpySUeydQFJqzqZoNgOoIGpMaaR9hP16HDtuW1P972JhhmAQeN7+h J5ioHopdMuo+5+FCZOPJKcJvKxHCQeq+G1WzIJWhvLwIs2D6duLJJTdOANE5RsxXjiRh dhqpZ2MqfTdjIf+UpSZnkwrDmiL7CPo0ziwMze8lweRq53yftU0E8hu91mmMMVPKgC4w w5RA== X-Gm-Message-State: AOAM532EnrWTUWAeiFP9Ho3DuzayM74g7rXwy0O1HEwxUcwvtJaT7L+F 6bmYqpvjc2MzilvrMmCWNJf7uqSJMNG+YEiAfVRdZw== X-Google-Smtp-Source: ABdhPJwaXiABsmttpq0abL+FY1DkbKr8FxxA6gSxIWp2Lq3V0jvddYBCy3+ENnEdd8oHMco7G1iYYIzkL6kvQl23mjM= X-Received: by 2002:a81:4524:: with SMTP id s36mr6060238ywa.331.1644477634424; Wed, 09 Feb 2022 23:20:34 -0800 (PST) MIME-Version: 1.0 References: <20220208073617.70342-1-songmuchun@bytedance.com> <20220208073617.70342-4-songmuchun@bytedance.com> In-Reply-To: From: Muchun Song Date: Thu, 10 Feb 2022 15:19:57 +0800 Message-ID: Subject: Re: [PATCH v4 3/5] mm: hugetlb: fix missing cache flush in copy_huge_page_from_user() To: Mike Kravetz Cc: Andrew Morton , zi.yan@cs.rutgers.edu, "Kirill A. Shutemov" , David Rientjes , Lars Persson , Zi Yan , Linux Memory Management List , LKML , Xiongchun duan , Fam Zheng Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 4E13220004 X-Stat-Signature: 64ytfoqbqg64i6sjj4o696ayq3z868yr X-Rspam-User: Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=bytedance-com.20210112.gappssmtp.com header.s=20210112 header.b=mnCQTtry; spf=pass (imf13.hostedemail.com: domain of songmuchun@bytedance.com designates 209.85.219.172 as permitted sender) smtp.mailfrom=songmuchun@bytedance.com; dmarc=pass (policy=none) header.from=bytedance.com X-Rspamd-Server: rspam05 X-HE-Tag: 1644477635-457876 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 Thu, Feb 10, 2022 at 3:07 AM Mike Kravetz wrote: > > On 2/7/22 23:36, Muchun Song wrote: > > The userfaultfd calls copy_huge_page_from_user() which does not do > > any cache flushing for the target page. Then the target page will > > be mapped to the user space with a different address (user address), > > which might have an alias issue with the kernel address used to copy > > the data from the user to. Fix this issue by flushing dcache in > > copy_huge_page_from_user(). > > Quick question. > > Should this also be done for the non-hugetlb case? Take a look at the > routines __mcopy_atomic() and mcopy_atomic_pte(). Or, is that somehow > handled? Actually, you are right. __mcopy_atomic() and mcopy_atomic_pte() should also be fixed. And shmem_mfill_atomic_pte() also should be fixed. I'll fix those places in the next version. Thanks. > > For this change, > Reviewed-by: Mike Kravetz Thanks Mike.