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=-3.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 DDCF3C2D0A8 for ; Mon, 28 Sep 2020 14:37:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 62D4A21941 for ; Mon, 28 Sep 2020 14:37:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="sztvg8Xs" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 62D4A21941 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 845738E0001; Mon, 28 Sep 2020 10:37:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7F5B46B005D; Mon, 28 Sep 2020 10:37:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 70B6E8E0001; Mon, 28 Sep 2020 10:37:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0130.hostedemail.com [216.40.44.130]) by kanga.kvack.org (Postfix) with ESMTP id 5CC646B005C for ; Mon, 28 Sep 2020 10:37:32 -0400 (EDT) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 1DDF58249980 for ; Mon, 28 Sep 2020 14:37:32 +0000 (UTC) X-FDA: 77312723544.29.lace26_0611e3127182 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin29.hostedemail.com (Postfix) with ESMTP id B1D5718086CD4 for ; Mon, 28 Sep 2020 14:37:31 +0000 (UTC) X-HE-Tag: lace26_0611e3127182 X-Filterd-Recvd-Size: 3157 Received: from mail-qk1-f171.google.com (mail-qk1-f171.google.com [209.85.222.171]) by imf03.hostedemail.com (Postfix) with ESMTP for ; Mon, 28 Sep 2020 14:37:31 +0000 (UTC) Received: by mail-qk1-f171.google.com with SMTP id c2so1120694qkf.10 for ; Mon, 28 Sep 2020 07:37:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to:cc; bh=9un1wrj3PTq7hOjdkXB7DO4gRSAxULKefYKMKy1C5EE=; b=sztvg8Xsp3jxgm/0E9EynYjZfFNu2om3bJC76o5nTDvNglwdbCuzzmaQb8H0b/+kSY LUom5AjRWc/hF4w0ETOs2jm1wqT0zGh1vuc5M3/ZBs3/zfz7dmxgE6KzxORiCiNGUiPL RBrLw7HYU4FfM98r3x12Yw990FCmvwnhzqGenpSsAUA/4NCDgeWNBaPSjVpcLTFEVQLn 2Bin7Mg8h807pMhAwhQOoIpKmn24mlFB3YoAXfnSv9HEtM+dsFWPjf45Is6StH8mR+7a KRbGND7jPeYCfYuyWceQ6JBLGbehOHQOxqZR9ZSBGurbcLsOqhfAj+KrtJBTulAEQhOo PfOg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to:cc; bh=9un1wrj3PTq7hOjdkXB7DO4gRSAxULKefYKMKy1C5EE=; b=hFNKkq9KHyJzJyQQHevLL9hVvc0zYA3KlHAG7X6ReDA3ymB2Q10z3h+eNkyjDrEL4q ciar4gwAWffqJd2ruonwhfc4L5SErH0GSqtzr0PSkqPQeKHqHfNLjrx7/qisXVnJEfzG KXYCUzIs6IstIz0BoOBe0IsCBbO8HaC4jbvBrBcMgb3g7go8juupIwipOUjPqCMaJTMD Cfz9MQo7sd5osVVsnRBLle9aj2CmEe5ncZYhE+z0Wt69eIGR5WOn0ovhMf6AIaIWbCLa NXKak9xz1fC3k9qy5kkH2g8q68IBpuxv/8MVePp8bqjxqjDv3PBTbyk3lnXjHxke3DjD 65tQ== X-Gm-Message-State: AOAM532kL1Wjh4rS6CwYHREoLcK3GYB9hyH+na0uSxElVX2F9/MrFpwa dfD+7UO4Ye54ndgu3V4uQAHip4baVx8qKVgkm9c= X-Google-Smtp-Source: ABdhPJzXG4Z+PUZWrDnmIZWqoyferBYQbQhL6n5BxoPBa6Vpji0JCsf+gAYNZMDhCNDDC2Ms05s3UYgj16JdaYd38zo= X-Received: by 2002:a37:a5d6:: with SMTP id o205mr1649836qke.314.1601303850655; Mon, 28 Sep 2020 07:37:30 -0700 (PDT) MIME-Version: 1.0 From: Hao Lee Date: Mon, 28 Sep 2020 22:37:17 +0800 Message-ID: Subject: Can we remove the checking of CONFIG_ARCH_HAS_PTE_SPECIAL in __vm_insert_mixed? To: npiggin@gmail.com Cc: dan.j.wiilliams@intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000009, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Sorry, the previous email is corrupted. This is a resending. In the current code, if the architecture supports PTE_SPECIAL, __vm_insert_mixed() becomes a simple encapsulation of insert_pfn() because it always calls insert_pfn() and never calls insert_page(). This behavior is inconsistent with the function's name. As described in commit 423bad600443 ("mm: add vm_insert_mixed"), this function is designed to supports _both_ raw pfns and pfns with struct page, but in architecture with PTE_SPECIAL, it treats the latter as the former. So, I think we'd better remove the checking of CONFIG_ARCH_HAS_PTE_SPECIAL to make the behavior consistent for all architectures. If my understanding is right, I can submit a patch to fix this. Thanks. Regards, Hao Lee