Message ID | 1a708210a8056aa356407e72973e00970523e7e2.1525356769.git.andreyknvl@google.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show
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[209.85.220.65]) by mx.google.com with SMTPS id 2sor1612358wml.0.2018.05.03.07.15.59 for <linux-mm@kvack.org> (Google Transport Security); Thu, 03 May 2018 07:16:00 -0700 (PDT) Received-SPF: pass (google.com: domain of andreyknvl@google.com designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=SCYKEXLS; spf=pass (google.com: domain of andreyknvl@google.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=andreyknvl@google.com; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :in-reply-to:references; bh=UK5wc6DlUcroqlO7Swx8mX58fL3XtYOgQeE0FdL7+yM=; b=SCYKEXLSpkNlZ9mHjShUuLWwNSiajDqZHo9U6ZQfP94nylXpVwhaK/sq9SWYSuw6qZ xgQ1LKQGfbq7VMeFIP6LF7phM9DOO4kNWoESi0QbI1EHcEFsPwSEJmupL1OyoB05vXoE TupctVtdSq13zTI46v73lUWLEIohw8yHPSyROzFIi/sfPuE5ulZNhFr++XsbAQL2/i3U l7FJtduUS2tb6945qKr4Ok8wb+PScpzEommAHb3yD+rJ3Hb9yz8ruCtvZSL6xpamwEIm ywOUlxxHQ0CTeZuLgI4GuOUP+T5FSGpLlZMwsCUky+i7P3jHK2Y42sb6Z0bEOVVTa/+W xRrg== X-Google-Smtp-Source: AB8JxZp3MQmZZ6oNm3X5fe1bQ1T4o6Ql+t77Nx3UuR1G4D5mj7PNDW0sv4E6Oua5EgFMYH61+7XlKQ== X-Received: by 10.28.142.149 with SMTP id q143mr14751135wmd.161.1525356959476; Thu, 03 May 2018 07:15:59 -0700 (PDT) Received: from andreyknvl0.muc.corp.google.com ([2a00:79e0:15:10:84be:a42a:826d:c530]) by smtp.gmail.com with ESMTPSA id u20-v6sm22090298wru.33.2018.05.03.07.15.57 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 03 May 2018 07:15:58 -0700 (PDT) From: Andrey Konovalov <andreyknvl@google.com> To: Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will.deacon@arm.com>, Jonathan Corbet <corbet@lwn.net>, Mark Rutland <mark.rutland@arm.com>, Robin Murphy <robin.murphy@arm.com>, Al Viro <viro@zeniv.linux.org.uk>, Andrey Konovalov <andreyknvl@google.com>, James Morse <james.morse@arm.com>, Kees Cook <keescook@chromium.org>, Bart Van Assche <bart.vanassche@wdc.com>, Kate Stewart <kstewart@linuxfoundation.org>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Thomas Gleixner <tglx@linutronix.de>, Philippe Ombredanne <pombredanne@nexb.com>, Andrew Morton <akpm@linux-foundation.org>, Ingo Molnar <mingo@kernel.org>, "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>, Dan Williams <dan.j.williams@intel.com>, "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>, Zi Yan <zi.yan@cs.rutgers.edu>, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: Dmitry Vyukov <dvyukov@google.com>, Kostya Serebryany <kcc@google.com>, Evgeniy Stepanov <eugenis@google.com>, Lee Smith <Lee.Smith@arm.com>, Ramana Radhakrishnan <Ramana.Radhakrishnan@arm.com>, Jacob Bramley <Jacob.Bramley@arm.com>, Ruben Ayrapetyan <Ruben.Ayrapetyan@arm.com>, Chintan Pandya <cpandya@codeaurora.org> Subject: [PATCH v2 6/6] arm64: update Documentation/arm64/tagged-pointers.txt Date: Thu, 3 May 2018 16:15:44 +0200 Message-Id: <1a708210a8056aa356407e72973e00970523e7e2.1525356769.git.andreyknvl@google.com> X-Mailer: git-send-email 2.17.0.441.gb46fe60e1d-goog In-Reply-To: <cover.1525356769.git.andreyknvl@google.com> References: <cover.1525356769.git.andreyknvl@google.com> In-Reply-To: <cover.1525356769.git.andreyknvl@google.com> References: <cover.1525356769.git.andreyknvl@google.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: <linux-mm.kvack.org> X-Virus-Scanned: ClamAV using ClamSMTP |
diff --git a/Documentation/arm64/tagged-pointers.txt b/Documentation/arm64/tagged-pointers.txt index a25a99e82bb1..361481283f00 100644 --- a/Documentation/arm64/tagged-pointers.txt +++ b/Documentation/arm64/tagged-pointers.txt @@ -35,8 +35,9 @@ Using non-zero address tags in any of these locations may result in an error code being returned, a (fatal) signal being raised, or other modes of failure. -For these reasons, passing non-zero address tags to the kernel via -system calls is forbidden, and using a non-zero address tag for sp is +Some initial work for supporting non-zero address tags passed to the +kernel via system calls has been done, but the kernel doesn't provide +any guarantees at this point. Using a non-zero address tag for sp is strongly discouraged. Programs maintaining a frame pointer and frame records that use non-zero
Add a note that work on passing tagged user pointers to the kernel via syscalls has started, but might not be complete yet. Signed-off-by: Andrey Konovalov <andreyknvl@google.com> --- Documentation/arm64/tagged-pointers.txt | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)