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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83846C433FE for ; Mon, 7 Mar 2022 18:48:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241187AbiCGSs7 (ORCPT ); Mon, 7 Mar 2022 13:48:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49612 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239995AbiCGSs6 (ORCPT ); Mon, 7 Mar 2022 13:48:58 -0500 Received: from mail-pj1-x102c.google.com (mail-pj1-x102c.google.com [IPv6:2607:f8b0:4864:20::102c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 177F74C788 for ; Mon, 7 Mar 2022 10:48:03 -0800 (PST) Received: by mail-pj1-x102c.google.com with SMTP id v4so14787276pjh.2 for ; Mon, 07 Mar 2022 10:48:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=8cawUedO3MiZdBH5IaNGoO6gaFsJGnxRPeumYwcEFvE=; b=HU6C9yy03NJRZkbgY1bu8iO3cicl+MngNKMUfRJ0jUqZnuC7P7bTL7AFMLcy+buiq9 a2YhYBWinbASKPzmHMYVSdz5m9lNWnLL8ggee0CRpLsqdTIjYcPFmObN0NJtEtBBblr9 K2DJOXUmuB66khzjw824WKgRyXhOWMVjGGEIKNg6opaZpOhSgkJcWCoXlSy5iI09Rn0E 76hToCG0ppU1mnblrRCNWBvX1Vp0aQnfOjs9Cc7h7G9HOKLkRyTyFRLPC8E/blD+FraJ 1ZJERAB+xBYPZK5l9ABvlsHQN6KVYlIYj3yQa7TO/jOtgsUwGT3inKQazYwKfe0cZdRn po4A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=8cawUedO3MiZdBH5IaNGoO6gaFsJGnxRPeumYwcEFvE=; b=jDcCLe0paDvyen+0aM7JVgdfdXliywEJgDCHPu6V7/9FUkIaF9ae4dTfIbb0PMy0ZE Mgk+QIDJ2tCXNgn/nluSR1z4ZtrQV6zvrg0CRK5CmiqlknftuBJ0VFErHcj6pPqrPn8J roZ/JepQFOv1BoJd4zL2O3++uP6Y2C2HLfw34Si4ovjJrTaK5CV99zGWq4N9cDx3NdZX eE5sD3Po6GsVvyJdgcuCs1XSD62ym18PqaQ6XZ+/TqPRoDA8/vMu2qyJrshAgEbu9rDF p9ZzTYpH6PqGbEIcBIbc6Z3lfcG06BcAagkaOS+vjmhrWtjLpQMKemkO2QBkciMtHIYe nwdQ== X-Gm-Message-State: AOAM531WQXvE/3ffT+HnoI5njSGZb3RBcUiWzZddfEB+UON7pygqA0bF Bg7Poaq70ji4qvH891TAECF4MJOCeOE= X-Google-Smtp-Source: ABdhPJzeg9uAJPZN+8w5f9UvK4956cDh6EgmDJiTjvWSZ1epk2qe7kLdihq+zwRF+gI9+OZz2RzWFQ== X-Received: by 2002:a17:90a:2c0b:b0:1be:da5a:b294 with SMTP id m11-20020a17090a2c0b00b001beda5ab294mr358642pjd.9.1646678882174; Mon, 07 Mar 2022 10:48:02 -0800 (PST) Received: from sc2-hs2-b1628.eng.vmware.com ([66.170.99.1]) by smtp.gmail.com with ESMTPSA id c18-20020a056a000ad200b004f0f9696578sm18624749pfl.141.2022.03.07.10.48.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Mar 2022 10:48:01 -0800 (PST) From: Nadav Amit X-Google-Original-From: Nadav Amit To: linux-man@vger.kernel.org Cc: Alejandro Colomar , "Michael Kerrisk )" , Peter Xu , David Hildenbrand , Nadav Amit Subject: [PATCH 1/2] ioctl_userfaultfd.2: add UFFD_FEATURE_EXACT_ADDRESS Date: Mon, 7 Mar 2022 18:48:51 +0000 Message-Id: <20220307184852.20351-1-namit@vmware.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-man@vger.kernel.org From: Nadav Amit Describe the new UFFD_FEATURE_EXACT_ADDRESS API feature. Signed-off-by: Nadav Amit --- man2/ioctl_userfaultfd.2 | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/man2/ioctl_userfaultfd.2 b/man2/ioctl_userfaultfd.2 index 504f61d4b..94480158e 100644 --- a/man2/ioctl_userfaultfd.2 +++ b/man2/ioctl_userfaultfd.2 @@ -214,6 +214,14 @@ memory accesses to the regions registered with userfaultfd. If this feature bit is set, .I uffd_msg.pagefault.feat.ptid will be set to the faulted thread ID for each page-fault message. +.TP +.BR UFFD_FEATURE_EXACT_ADDRESS " (since Linux 5.18)" +If this feature bit is set, +.I uffd_msg.pagefault.address +will be set to the exact page-fault address that was reported by the hardware, +and will not mask the offset within the page. +Note that old Linux versions might indicate the exact address as well, +even though the feature bit is not set. .PP The returned .I ioctls -- 2.25.1