[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [XEN PATCH] x86/guest_walk: address violations of MISRA C:2012 Rule 8.3
- To: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>, Federico Serafini <federico.serafini@xxxxxxxxxxx>
- From: Jan Beulich <jbeulich@xxxxxxxx>
- Date: Tue, 28 Nov 2023 14:43:34 +0100
- Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=suse.com; dmarc=pass action=none header.from=suse.com; dkim=pass header.d=suse.com; arc=none
- Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=bRnlGgR3goSptBX4lELfDp94qd3aU64P1ZdD374ZpQY=; b=GDM3OmJZtHDFwq72ODlfP7Q+v0S55yZS9KvB4zoswFSoS4DHAZSsEK8Y1A++l1ABH/oafWkFb6GMSvu04m9yLGC54gCpmnZZ5/grqlnkQ4eBVVQ+v19oZqlWkT401BGH3opsHaCxKn91bRToDItfx5WdqkLk7X+lwG9UrTUbo3n+vPhGJ4RD6WHAmdBcWtij0LJNyQuUtLSILXFMVgzUubYhgpFHtQwbDBv/0/ssd79lErzmohR1OUMvYpEh9s44hVSn4TCvzYx9QfJVgHAo2/bMKjnV4mm5wOLZWGR/PwIgxXc7h8kU7/gcNP7w1xJ1t3rkD9Z9vhMH2jynyM448g==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=RFjOp1rbzcCkBiThiDqzgN3NowHPl5YxYHiThpotWIAd4XYs6atX+JsZwHQAPSsk0YosGHdKFsRxJD1Jxx5a9N3ePDlQ7POF+qRYXT+Efa+Kb+Bm2rq7jfjrcv3wBc91uzB8IBc3PAYDP855CwI4jBMX9h0E/1FlaDuo2R1YRPFMvk5qUJv/VT7MAwc35N7wSNe0Gs+men1C9aRcTL+BIpUCGZZSfZZ9lw3V9OryrC6lcsj9xVehGwa/Wz/QTyQEEYmxX6ptc4E28qnvicyDK1N1LKkPwnjhT2g3xOQHe/jQB1qhjHvmJS/Aszy7YUyqnNVtOI0uKOEUYfvxY9HEPw==
- Authentication-results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=suse.com;
- Autocrypt: addr=jbeulich@xxxxxxxx; keydata= xsDiBFk3nEQRBADAEaSw6zC/EJkiwGPXbWtPxl2xCdSoeepS07jW8UgcHNurfHvUzogEq5xk hu507c3BarVjyWCJOylMNR98Yd8VqD9UfmX0Hb8/BrA+Hl6/DB/eqGptrf4BSRwcZQM32aZK 7Pj2XbGWIUrZrd70x1eAP9QE3P79Y2oLrsCgbZJfEwCgvz9JjGmQqQkRiTVzlZVCJYcyGGsD /0tbFCzD2h20ahe8rC1gbb3K3qk+LpBtvjBu1RY9drYk0NymiGbJWZgab6t1jM7sk2vuf0Py O9Hf9XBmK0uE9IgMaiCpc32XV9oASz6UJebwkX+zF2jG5I1BfnO9g7KlotcA/v5ClMjgo6Gl MDY4HxoSRu3i1cqqSDtVlt+AOVBJBACrZcnHAUSuCXBPy0jOlBhxPqRWv6ND4c9PH1xjQ3NP nxJuMBS8rnNg22uyfAgmBKNLpLgAGVRMZGaGoJObGf72s6TeIqKJo/LtggAS9qAUiuKVnygo 3wjfkS9A3DRO+SpU7JqWdsveeIQyeyEJ/8PTowmSQLakF+3fote9ybzd880fSmFuIEJldWxp Y2ggPGpiZXVsaWNoQHN1c2UuY29tPsJgBBMRAgAgBQJZN5xEAhsDBgsJCAcDAgQVAggDBBYC AwECHgECF4AACgkQoDSui/t3IH4J+wCfQ5jHdEjCRHj23O/5ttg9r9OIruwAn3103WUITZee e7Sbg12UgcQ5lv7SzsFNBFk3nEQQCACCuTjCjFOUdi5Nm244F+78kLghRcin/awv+IrTcIWF hUpSs1Y91iQQ7KItirz5uwCPlwejSJDQJLIS+QtJHaXDXeV6NI0Uef1hP20+y8qydDiVkv6l IreXjTb7DvksRgJNvCkWtYnlS3mYvQ9NzS9PhyALWbXnH6sIJd2O9lKS1Mrfq+y0IXCP10eS FFGg+Av3IQeFatkJAyju0PPthyTqxSI4lZYuJVPknzgaeuJv/2NccrPvmeDg6Coe7ZIeQ8Yj t0ARxu2xytAkkLCel1Lz1WLmwLstV30g80nkgZf/wr+/BXJW/oIvRlonUkxv+IbBM3dX2OV8 AmRv1ySWPTP7AAMFB/9PQK/VtlNUJvg8GXj9ootzrteGfVZVVT4XBJkfwBcpC/XcPzldjv+3 HYudvpdNK3lLujXeA5fLOH+Z/G9WBc5pFVSMocI71I8bT8lIAzreg0WvkWg5V2WZsUMlnDL9 mpwIGFhlbM3gfDMs7MPMu8YQRFVdUvtSpaAs8OFfGQ0ia3LGZcjA6Ik2+xcqscEJzNH+qh8V m5jjp28yZgaqTaRbg3M/+MTbMpicpZuqF4rnB0AQD12/3BNWDR6bmh+EkYSMcEIpQmBM51qM EKYTQGybRCjpnKHGOxG0rfFY1085mBDZCH5Kx0cl0HVJuQKC+dV2ZY5AqjcKwAxpE75MLFkr wkkEGBECAAkFAlk3nEQCGwwACgkQoDSui/t3IH7nnwCfcJWUDUFKdCsBH/E5d+0ZnMQi+G0A nAuWpQkjM1ASeQwSHEeAWPgskBQL
- Cc: consulting@xxxxxxxxxxx, Roger Pau Monné <roger.pau@xxxxxxxxxx>, Wei Liu <wl@xxxxxxx>, George Dunlap <george.dunlap@xxxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxxx
- Delivery-date: Tue, 28 Nov 2023 13:43:52 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
On 28.11.2023 14:17, Andrew Cooper wrote:
> On 28/11/2023 1:00 pm, Jan Beulich wrote:
>> On 28.11.2023 10:46, Federico Serafini wrote:
>>> Uniform declaration and definition of guest_walk_tables() using
>>> parameter name "pfec_walk":
>>> this name highlights the connection with PFEC_* constants and it is
>>> consistent with the use of the parameter within function body.
>>> No functional change.
>>>
>>> Signed-off-by: Federico Serafini <federico.serafini@xxxxxxxxxxx>
>> I'm curious what other x86 maintainers think. I for one don't like this,
>> but not enough to object if others are happy. That said, there was earlier
>> discussion (and perhaps even a patch), yet without a reference I don't
>> think I can locate this among all the Misra bits and pieces.
>
> I looked at this and wanted a bit of time to think.
>
> Sadly, this code is half way through some cleanup, which started before
> speculation and will continue in my copious free time.
>
> It's wrong to be passing PFEC_* constants, and that's why I renamed pfec
> -> walk the last time I was fixing security bugs here (indeed, passing
> the wrong constant here *was* the security issue). I missed the
> prototype while fixing the implementation.
>
> At some point, PFEC_* will no longer be passed in.
>
> Therefore I'd far rather this was a one-line change for the declaration
> changing pfec -> walk.
So that was what Federico originally had. Did you see my response at
https://lists.xenproject.org/archives/html/xen-devel/2023-07/msg00122.html ?
While I certainly agree with your plans (as far as I understand them),
doing as you suggest would make it harder to spot what values are correct
to pass to the function today. With a suitable new set of constants and
perhaps even a proper typedef, such confusion would likely not arise.
Jan
|
