From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id aL5gMu/kkV9pSAAAWB0awg (envelope-from ) for ; Thu, 22 Oct 2020 16:00:47 -0400 Received: by simark.ca (Postfix, from userid 112) id CC51A1E89B; Thu, 22 Oct 2020 16:00:47 -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 BA3731E552 for ; Thu, 22 Oct 2020 16:00:45 -0400 (EDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 3183E39874D6; Thu, 22 Oct 2020 20:00:45 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 3183E39874D6 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1603396845; bh=eEzuSGiJ0ZJFZtwkA95k3GdVR1EZp3VzZaV6JuYm9P4=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=hQAPmwMx0gKr8jDMymuj7H00Kwi3LaC5FAMTLigWH8JK8rrdfJAVUV5jjBbwmUX/2 FaB6Fakh1ydb9Rpuwq5ZLNzFXzvNHJVw6oE2ZBqhZS0E3qXUHiglBB+8P5uoZd9gSo gbvQE4BA1yD6WQ472PLZdBH9Cati9Psq7KeScoRo= Received: from mail-qk1-x744.google.com (mail-qk1-x744.google.com [IPv6:2607:f8b0:4864:20::744]) by sourceware.org (Postfix) with ESMTPS id 562C039874F1 for ; Thu, 22 Oct 2020 20:00:42 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 562C039874F1 Received: by mail-qk1-x744.google.com with SMTP id x20so3106626qkn.1 for ; Thu, 22 Oct 2020 13:00:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=eEzuSGiJ0ZJFZtwkA95k3GdVR1EZp3VzZaV6JuYm9P4=; b=lak4oPveKjhYZeKMDQp86k1lTiYj5UU0E99kQexk5ysBj0KSUXQzNe2pal6XniE8Kz FlcmErjQyTlr3yCLimxmIEoQQ+A4+ipY4xKFcZX7ULK7dH2mZmfwDP+B7eXrg0IcQ6Z4 tdakOKpdI5b+DnPq7kcHOe5IEpAE5DCiML0Y9pLtwOAVX4MIRwQOWCX/62plzaqEqCXN Tifq2E0Cp5jl3jCIr7w8xIaAlmR7jiJU0yKx7pR15vTBGEIPWiOsCQJxHAJpTsw64cJX IyfTzCYWE0mmQnjVJefJCEcMegxheIknXJMiwAAxu0iQRvCCbdXC2bwc9I7jRly4DGTx kK3g== X-Gm-Message-State: AOAM533ntg9vJWDoAU1TPfmQBcxNKa1vvS9bVm/hNiU/5JJiFKXbxuia JkpAeRYn05VU1LPBJF6dYqvhQeA+ohVC4Q== X-Google-Smtp-Source: ABdhPJwo+RTGV2ZZnKJuzfVmOBrgPxxrgsP8MXEQL8zeq5qNdwkRxwxVS8zBJ4aUU8jbYzqxi0ENiw== X-Received: by 2002:a37:9d0c:: with SMTP id g12mr4180904qke.264.1603396841643; Thu, 22 Oct 2020 13:00:41 -0700 (PDT) Received: from localhost.localdomain ([2804:7f0:8284:1487:b9b1:f72a:8f1:600]) by smtp.gmail.com with ESMTPSA id a21sm1711208qkk.98.2020.10.22.13.00.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 22 Oct 2020 13:00:41 -0700 (PDT) To: gdb-patches@sourceware.org Subject: [PATCH v2 07/24] Documentation for memory tagging remote packets Date: Thu, 22 Oct 2020 16:59:57 -0300 Message-Id: <20201022200014.5189-8-luis.machado@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201022200014.5189-1-luis.machado@linaro.org> References: <20201022200014.5189-1-luis.machado@linaro.org> 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 Errors-To: gdb-patches-bounces@sourceware.org Sender: "Gdb-patches" Updates on v2: - Update documentation to mention the packet's type field. -- Document the remote packet changes to support memory tagging. gdb/doc/ChangeLog: YYYY-MM-DD Luis Machado * gdb.texinfo (General Query Packets): Document qMemTags and QMemTags. Document the "memory-tagging" feature. --- gdb/doc/gdb.texinfo | 90 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 90 insertions(+) diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index 2636b6f990..b778e48dd4 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -40762,6 +40762,83 @@ is a sequence of thread IDs, @var{threadid} (eight hex digits), from the target. See @code{remote.c:parse_threadlist_response()}. @end table +@item qMemTags:@var{start address},@var{length}:@var{type} +@cindex fetch memory tags +@cindex @samp{qMemTags} packet +Fetch memory tags of type @var{type} from the address range +@r{[}@var{start address}, @var{start address} + @var{length}@r{)}. The target +is responsible for calculating how many tags will be returned, as this is +architecture-specific. + +@var{start address} is the starting address of the memory range. + +@var{length} is the length, in bytes, of the memory range. + +@var{type} is the type of tag, a signed integer, the request wants to fetch. + +Reply: +@table @samp +@item @var{mxx}@dots{} +Hex encoded sequence of uninterpreted bytes, @var{xx}@dots{}, representing the +tags found in the request memory range. + +@item E @var{nn} +An error occured. This means that fetching of memory tags failed for some +reason. + +@item @w{} +An empty reply indicates that @samp{qMemTags} is not supported by the stub, +although this should not happen given @value{GDBN} will only send this packet +if the stub has advertised support for memory tagging via @samp{qSupported}. +@end table + +@item QMemTags:@var{start address},@var{length}:@var{type}:@var{tag bytes} +@cindex store memory tags +@cindex @samp{QMemTags} packet +Store memory tags of type @var{type} to the address range +@r{[}@var{start address}, @var{start address} + @var{length}@r{)}. The target +is responsible for interpreting the type, the tag bytes and modifying the +memory tag granules accordingly, given this is architecture-specific. + +The interpretation of how many tags should be written to how many memory tag +granules is also architecture-specific. The behavior is +implementation-specific, but the following is suggested. + +If the number of memory tags, @var{nt}, is greater than or equal to the +number of memory tag granules, @var{ng}, only @var{ng} tags will be +stored. + +If @var{nt} is less than @var{ng}, the behavior is that of a fill operation, +and the tag bytes will be used as a pattern that will get repeated until +@var{ng} tags are stored. + +@var{start address} is the starting address of the memory range. The address +does not have any restriction on alignment or size. + +@var{length} is the length, in bytes, of the memory range. + +@var{type} is the type of tag, a signed integer, the request wants to store. + +@var{tag bytes} is a sequence of hex encoded uninterpreted bytes which will be +interpreted by the target. Each pair of hex digits is interpreted as a +single byte. + +Reply: +@table @samp +@item OK +The request was successful and the memory tag granules were modified +accordingly. + +@item E @var{nn} +An error occured. This means that modifying the memory tag granules failed +for some reason. + +@item @w{} +An empty reply indicates that @samp{QMemTags} is not supported by the stub, +although this should not happen given @value{GDBN} will only send this packet +if the stub has advertised support for memory tagging via @samp{qSupported}. +@end table + @item qOffsets @cindex section offsets, remote request @cindex @samp{qOffsets} packet @@ -41429,6 +41506,11 @@ These are the currently defined stub features and their properties: @tab @samp{-} @tab No +@item @samp{memory-tagging} +@tab No +@tab @samp{-} +@tab No + @end multitable These are the currently defined stub features, in more detail: @@ -41643,6 +41725,14 @@ The remote stub understands the @samp{QThreadEvents} packet. @item no-resumed The remote stub reports the @samp{N} stop reply. +@item memory-tagging +The remote stub supports and implements the required memory tagging +functionality and understands the @samp{qMemTags} and @samp{QMemTags} packets. + +For AArch64 GNU/Linux systems, this feature also requires access to the +@file{/proc/@var{pid}/smaps} file so memory mapping page flags can be inspected. +This is done via the @samp{vFile} requests. + @end table @item qSymbol:: -- 2.17.1