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 947B6C678D4 for ; Tue, 7 Mar 2023 10:33:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230258AbjCGKdf (ORCPT ); Tue, 7 Mar 2023 05:33:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43204 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230189AbjCGKdF (ORCPT ); Tue, 7 Mar 2023 05:33:05 -0500 Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7D7AA72A6; Tue, 7 Mar 2023 02:32:57 -0800 (PST) Received: from zn.tnic (p5de8e9fe.dip0.t-ipconnect.de [93.232.233.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id D9B1F1EC0683; Tue, 7 Mar 2023 11:32:55 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1678185175; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=TSaRNnuYPMpqfKbVyvY5NfwUuBAd5KNTO4zFjqwOrxs=; b=L1XBCtD23na6R3E13elS6V0ZP5T2POm9e9hiV/ka1IMvkPwbFMAaKSQRD70gxI+wvR11FF roVJC30ow7iteUYrsOIzCJ2K4IwqmiCNeCZ4S7YrnBe99Ta9WPZTuwVAKPjZAHFH6BfcSS dQ3+Z1erhtgZDIYxF6Y1uAhTxiZbhgc= Date: Tue, 7 Mar 2023 11:32:51 +0100 From: Borislav Petkov To: "Edgecombe, Rick P" Cc: "david@redhat.com" , "bsingharora@gmail.com" , "hpa@zytor.com" , "Syromiatnikov, Eugene" , "peterz@infradead.org" , "rdunlap@infradead.org" , "keescook@chromium.org" , "Yu, Yu-cheng" , "dave.hansen@linux.intel.com" , "kirill.shutemov@linux.intel.com" , "Eranian, Stephane" , "linux-mm@kvack.org" , "fweimer@redhat.com" , "nadav.amit@gmail.com" , "jannh@google.com" , "dethoma@microsoft.com" , "kcc@google.com" , "linux-arch@vger.kernel.org" , "pavel@ucw.cz" , "oleg@redhat.com" , "hjl.tools@gmail.com" , "Yang, Weijiang" , "Lutomirski, Andy" , "linux-doc@vger.kernel.org" , "arnd@arndb.de" , "tglx@linutronix.de" , "Schimpe, Christina" , "mike.kravetz@oracle.com" , "x86@kernel.org" , "akpm@linux-foundation.org" , "debug@rivosinc.com" , "jamorris@linux.microsoft.com" , "john.allen@amd.com" , "rppt@kernel.org" , "andrew.cooper3@citrix.com" , "mingo@redhat.com" , "corbet@lwn.net" , "linux-kernel@vger.kernel.org" , "linux-api@vger.kernel.org" , "gorcunov@gmail.com" Subject: Re: [PATCH v7 21/41] mm: Add guard pages around a shadow stack. Message-ID: <20230307103251.GAZAcS0zpon573Ox3N@fat_crate.local> References: <20230227222957.24501-1-rick.p.edgecombe@intel.com> <20230227222957.24501-22-rick.p.edgecombe@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On Tue, Mar 07, 2023 at 01:29:50AM +0000, Edgecombe, Rick P wrote: > On Mon, 2023-03-06 at 09:08 +0100, Borislav Petkov wrote: > > Just typos: > > All seem reasonable to me. Thanks. > > For using the log verbiage for the comment, it is quite big. Does > something like this seem reasonable? Yeah, it does. I wouldn't want to lose that explanation in a commit message. However, this special aspect pertains to the shstk implementation in x86 but the code is generic mm and such arch-specific comments are kinda unfitting there. I wonder if it would be better if you could stick that explanation somewhere in arch/x86/ and only refer to it in a short comment above VM_SHADOW_STACK check in stack_guard_start_gap()... Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette