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(p200300cbc707a1000e2041dac49b8974.dip0.t-ipconnect.de. [2003:cb:c707:a100:e20:41da:c49b:8974]) by smtp.gmail.com with ESMTPSA id w2-20020a5d6802000000b002c7163660a9sm12202423wru.105.2023.03.07.02.44.03 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 07 Mar 2023 02:44:05 -0800 (PST) Message-ID: Date: Tue, 7 Mar 2023 11:44:03 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.8.0 Subject: Re: [PATCH v7 21/41] mm: Add guard pages around a shadow stack. Content-Language: en-US To: Borislav Petkov , "Edgecombe, Rick P" Cc: "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" References: <20230227222957.24501-1-rick.p.edgecombe@intel.com> <20230227222957.24501-22-rick.p.edgecombe@intel.com> <20230307103251.GAZAcS0zpon573Ox3N@fat_crate.local> From: David Hildenbrand Organization: Red Hat In-Reply-To: <20230307103251.GAZAcS0zpon573Ox3N@fat_crate.local> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On 07.03.23 11:32, Borislav Petkov wrote: > 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()... +1 -- Thanks, David / dhildenb