From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id gfS+K7rUml/FCQAAWB0awg (envelope-from ) for ; Thu, 29 Oct 2020 10:42:02 -0400 Received: by simark.ca (Postfix, from userid 112) id A6AFE1EFC1; Thu, 29 Oct 2020 10:42:02 -0400 (EDT) X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on simark.ca X-Spam-Level: X-Spam-Status: No, score=-1.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPS id CE7DA1E58E for ; Thu, 29 Oct 2020 10:42:01 -0400 (EDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 5DCFB3854832; Thu, 29 Oct 2020 14:42:01 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 5DCFB3854832 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1603982521; bh=EsuapYKEN500brMNduzSK/6WBCj9KOqgsAcY7kup8IQ=; h=Subject:To:References:Date:In-Reply-To:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=lMj2DJcVmNUmOPoE5W5hNm1+zFdSlzRmte2JxCwRKoemyX1G+nb9BH9tl+Z5VtKhJ AEKpExvkoMyp72pNDgh2LJSqGAy7oF/R15OG8LUx+Fu037bGPZWeKdC3HbSyjSLwMg T/+BA5+hqrxxnle0yFBwT633phoQjFgGB2FHyVlc= Received: from mail-qt1-x841.google.com (mail-qt1-x841.google.com [IPv6:2607:f8b0:4864:20::841]) by sourceware.org (Postfix) with ESMTPS id E4F883861034 for ; Thu, 29 Oct 2020 14:41:58 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org E4F883861034 Received: by mail-qt1-x841.google.com with SMTP id c5so1964667qtw.3 for ; Thu, 29 Oct 2020 07:41:58 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=EsuapYKEN500brMNduzSK/6WBCj9KOqgsAcY7kup8IQ=; b=qARIeOOeMvctj7siRe292kLaGDnZu9Sptb6pV81VsIPT/u7FjVaouaikJ6SXQEzntJ O9yedDOu70gGgJKEDdXArsI0y2sPo7uDV1JGnIUwFL3u5V04RIbX6ObNWofCCJMKU24x qHibCBKCUxC3WnKdkXjeJLxcZ4V6d+p7uBDY/cLH9aozK+t80Xk/7bIoVmifwUig7LqL ecXkcc3Rp7Sr5A/4zwHFHm8saDhPf/8qNCbsjHMB/Lswuzbu5sPTqCcYAW/uFrTlL2G6 V7iUWqS/aeO3k4aPfWsqambQaFBgjeOEndVm5vNNzFPIRrPk6ZGJ7GwI4PdXozTl5Bf4 cTuQ== X-Gm-Message-State: AOAM530K6pr6Me7nDj8gtUTwrQm9PSi8b7UsGrOZZRv9DtjVsx3ApBz7 RtXFSZkWLe0YqrfZ6XqSEq/Zhg== X-Google-Smtp-Source: ABdhPJzV38BXTF4SxKJZir0iuopxpM6MWne0Q+cQPo48CbtV9lBuG92D/OuN6tq0c7KOXqzza7Gj3w== X-Received: by 2002:ac8:4295:: with SMTP id o21mr3793732qtl.313.1603982517949; Thu, 29 Oct 2020 07:41:57 -0700 (PDT) Received: from ?IPv6:2804:7f0:8284:1487:6a9e:2ef6:314b:f393? ([2804:7f0:8284:1487:6a9e:2ef6:314b:f393]) by smtp.gmail.com with ESMTPSA id z134sm1207742qka.21.2020.10.29.07.41.55 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 29 Oct 2020 07:41:57 -0700 (PDT) Subject: Re: [PATCH v2 03/24] Add GDB-side remote target support for memory tagging To: Alan Hayward References: <20201022200014.5189-1-luis.machado@linaro.org> <20201022200014.5189-4-luis.machado@linaro.org> <95EFCF01-4654-467A-BEC1-C516F33F44AF@arm.com> Message-ID: Date: Thu, 29 Oct 2020 11:41:54 -0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <95EFCF01-4654-467A-BEC1-C516F33F44AF@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Luis Machado via Gdb-patches Reply-To: Luis Machado Cc: "david.spickett@linaro.org" , nd , "gdb-patches\\@sourceware.org" Errors-To: gdb-patches-bounces@sourceware.org Sender: "Gdb-patches" On 10/29/20 11:22 AM, Alan Hayward wrote: > > >> On 22 Oct 2020, at 20:59, Luis Machado wrote: >> >> Updates for v2: >> >> - Add type field to target hooks. >> - Add type data to qMemTags and QMemTags. The packets now look like this: >> >> qMemTags:
,: >> QMemTags:
,:: >> >> -- >> >> This patch adds memory tagging support to GDB's remote side, with >> packet string checks, new packet support and an implementation of >> the two new tags methods fetch_atags and store_atags. >> >> GDBserver needs to know how to read/write allocation tags, since that is >> done via ptrace. It doesn't need to know about logical tags. >> >> The new packets are: >> >> qMemTags:
, >> -- >> >> Reads tags from the address range [
,
) >> >> QMemTags:
,: >> -- >> Writes the tags represented by the uninterpreted bytes to the address range >> [
,
). >> >> The interpretation of what to do with the tag bytes is up to the arch-specific >> code. >> >> Note that these new packets consider the case of packet size overflow as an >> error, given the common use case is to read/write only a few memory tags at >> a time. Having to use a couple new packets for multi-part transfers wouldn't >> make sense for the little use it would have. >> > > Minor nit: "Having to use a couple new packets”. Even after adding an “of” I’m > not fully sure if that’s what you meant to write. > > I guess I could make it more clear. What I meant to say is that we would need to come up with new packets (in addition to the couple ones we've added) to extend the current design to cope with multi-part transfers of tags in the remote protocol.