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=-8.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 1605EC433E3 for ; Mon, 22 Mar 2021 09:14:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BAA1061980 for ; Mon, 22 Mar 2021 09:14:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229946AbhCVJOJ (ORCPT ); Mon, 22 Mar 2021 05:14:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229953AbhCVJNs (ORCPT ); Mon, 22 Mar 2021 05:13:48 -0400 Received: from mail-lj1-x22a.google.com (mail-lj1-x22a.google.com [IPv6:2a00:1450:4864:20::22a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C9E93C061574 for ; Mon, 22 Mar 2021 02:13:47 -0700 (PDT) Received: by mail-lj1-x22a.google.com with SMTP id f26so20089553ljp.8 for ; Mon, 22 Mar 2021 02:13:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=shutemov-name.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=oeb+PAJt63mP/90xgvzuCXrpKeElQVZ936dwu02SQSs=; b=vzzAMo3aw5fcRzSX+G3c49ViQ1+a2Z3evKUgoQIyGT2wxwNav+apCuqkclUmMbnlaN zqGSCJfOcEWSq8ssQkZwj+LJc/Ty/8pfNOYsNDllj78fk8jwexa9D9uyOL/WKSj70Usr b/FnwK1wkHphsBamUAgAH2GFPKESAUjtpENKMfga60ik9YyY9NFua3ZxI2CL7RjVZn6K aSBDoq5ZZSIdeXCzP2lF/W52ZHtaKfzU8cZU95Kpzj3XmLXkes3IYhX0QRvKkBO7r6B0 waP7sq+Dfk9clJC3leU31iwsQYM3gisuCqBiHUGWg7CkT3CIms5CXdbp1NC4TqHkgmOp F7mw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=oeb+PAJt63mP/90xgvzuCXrpKeElQVZ936dwu02SQSs=; b=XM07VOv0bLPDG2RXnJNNwVUwBDalbiLH9y9X1Q7fHTsjACrbUmJphSnzKQJlZNy7B4 E+PcqgrLf0mYC4a8yfC2AeHCUrtrY92zKXXiCYtx2ieumaW2bYK1/TylZ7u33aFNH39p XIyno17nDcclFy2UiWskPAjQjnvHhpjfNZHtg5hOXUivawCPBszDSYJxpKE/YX9E+f0n MckUVdDHMxLFcsxTMGCWWazALp+Ke10rpdvtE5rv6JQLrMlG8T2o9N/4j+FrwljkeeQM 8m+URGnmgFHTzdheOpvmc/xTP94mmGkwIsN9yWrGnWnONuYHfs/TLKdsD2QQprCOBnuC BZsg== X-Gm-Message-State: AOAM530Isr9ksDQxihOP7TD8pssnHehxZrvriK2HzR+CdKscwEmYEGff T9urgdUok7dfi7ABKbGhsK8ICg== X-Google-Smtp-Source: ABdhPJxTA9cuU0Tj6UyaICAHV1a7JefKb/E4L50FuiajXX8hVPb/1lKfnwtXmcDOwPFeHA+rJ9ZfkA== X-Received: by 2002:a05:651c:2005:: with SMTP id s5mr9499871ljo.491.1616404424784; Mon, 22 Mar 2021 02:13:44 -0700 (PDT) Received: from box.localdomain ([86.57.175.117]) by smtp.gmail.com with ESMTPSA id b39sm1792329ljf.68.2021.03.22.02.13.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 Mar 2021 02:13:44 -0700 (PDT) Received: by box.localdomain (Postfix, from userid 1000) id A074B101DEB; Mon, 22 Mar 2021 12:13:51 +0300 (+03) Date: Mon, 22 Mar 2021 12:13:51 +0300 From: "Kirill A. Shutemov" To: Yu-cheng Yu Cc: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Christoph Hellwig Subject: Re: [PATCH v23 07/28] x86/mm: Remove _PAGE_DIRTY from kernel RO pages Message-ID: <20210322091351.ulemcluuhqkzuwkm@box> References: <20210316151054.5405-1-yu-cheng.yu@intel.com> <20210316151054.5405-8-yu-cheng.yu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210316151054.5405-8-yu-cheng.yu@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 16, 2021 at 08:10:33AM -0700, Yu-cheng Yu wrote: > The x86 family of processors do not directly create read-only and Dirty > PTEs. These PTEs are created by software. One such case is that kernel > read-only pages are historically setup as Dirty. > > New processors that support Shadow Stack regard read-only and Dirty PTEs as > shadow stack pages. This results in ambiguity between shadow stack and > kernel read-only pages. To resolve this, removed Dirty from kernel read- > only pages. > > Signed-off-by: Yu-cheng Yu > Cc: "H. Peter Anvin" > Cc: Kees Cook > Cc: Thomas Gleixner > Cc: Dave Hansen > Cc: Christoph Hellwig > Cc: Andy Lutomirski > Cc: Ingo Molnar > Cc: Borislav Petkov > Cc: Peter Zijlstra Looks good to me. Reviewed-by: Kirill A. Shutemov -- Kirill A. Shutemov