Date: Tue, 11 Apr 2017 23:56:01 +0200
From: Borislav Petkov <bp@suse.de>
To: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>, Thomas Gleixner <tglx@linutronix.de>,
        "H. Peter Anvin" <hpa@zytor.com>, Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Brian Gerst <brgerst@gmail.com>, Chris Metcalf <cmetcalf@mellanox.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Masami Hiramatsu <mhiramat@kernel.org>, Huang Rui <ray.huang@amd.com>,
        Jiri Slaby <jslaby@suse.cz>, Jonathan Corbet <corbet@lwn.net>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Paul Gortmaker <paul.gortmaker@windriver.com>,
        Vlastimil Babka <vbabka@suse.cz>, Chen Yucong <slaoub@gmail.com>,
        Alexandre Julliard <julliard@winehq.org>, Stas Sergeev <stsp@list.ru>,
        Fenghua Yu <fenghua.yu@intel.com>,
        "Ravi V. Shankar" <ravi.v.shankar@intel.com>,
        Shuah Khan <shuah@kernel.org>, linux-kernel@vger.kernel.org,
        x86@kernel.org, linux-msdos@vger.kernel.org, wine-devel@winehq.org,
        Adam Buchbinder <adam.buchbinder@gmail.com>,
        Colin Ian King <colin.king@canonical.com>,
        Lorenzo Stoakes <lstoakes@gmail.com>,
        Qiaowei Ren <qiaowei.ren@intel.com>,
        Nathan Howard <liverlint@gmail.com>,
        Adan Hawthorn <adanhawthorn@gmail.com>, Joe Perches <joe@perches.com>
Subject: Re: [v6 PATCH 01/21] x86/mpx: Use signed variables to compute
 effective addresses
Message-ID: <20170411215601.kycakoyogyfdosi5@pd.tnic>
References: <20170308003254.27833-1-ricardo.neri-calderon@linux.intel.com>
 <20170308003254.27833-2-ricardo.neri-calderon@linux.intel.com>
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On Tue, Mar 07, 2017 at 04:32:34PM -0800, Ricardo Neri wrote:
> Even though memory addresses are unsigned. The operands used to compute the

				... unsigned, the operands ...

> effective address do have a sign. This is true for the r/m part of the
> ModRM byte, the base and index parts of the SiB byte as well as the
> displacement. Thus, signed variables shall be used when computing the
> effective address from these operands. Once the signed effective address
> has been computed, it is casted to an unsigned long to determine the
> linear address.
> 
> Variables are renamed to better reflect the type of address being
> computed.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--