Received-SPF: pass (google.com: domain of linux-kernel+bounces-7490-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) client-ip=2604:1380:40f1:3f00::1;
Message-ID: <fbc0ae3f-ced6-39c0-2e9c-f5d56cb26d43@intel.com>
Date: Wed, 20 Dec 2023 14:12:17 -0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101
 Thunderbird/102.6.1
Subject: Re: [Intel-wired-lan] [PATCH v5 iwl-next] i40e: Use correct buffer
 size in i40e_dbg_command_read
Content-Language: en-US
To: "Nelson, Shannon" <shannon.nelson@amd.com>, "Pucha, HimasekharX Reddy"
	<himasekharx.reddy.pucha@intel.com>, Kunwu Chan <chentao@kylinos.cn>,
	"Brandeburg, Jesse" <jesse.brandeburg@intel.com>, "davem@davemloft.net"
	<davem@davemloft.net>, "edumazet@google.com" <edumazet@google.com>,
	"kuba@kernel.org" <kuba@kernel.org>, "pabeni@redhat.com" <pabeni@redhat.com>,
	"jeffrey.t.kirsher@intel.com" <jeffrey.t.kirsher@intel.com>
CC: Kunwu Chan <kunwu.chan@hotmail.com>, "netdev@vger.kernel.org"
	<netdev@vger.kernel.org>, "linux-kernel@vger.kernel.org"
	<linux-kernel@vger.kernel.org>, "Lobakin, Aleksander"
	<aleksander.lobakin@intel.com>, "intel-wired-lan@lists.osuosl.org"
	<intel-wired-lan@lists.osuosl.org>, Simon Horman <horms@kernel.org>
References: <20231208031950.47410-1-chentao@kylinos.cn>
 <BL0PR11MB31226B042632413AB8C12D63BD90A@BL0PR11MB3122.namprd11.prod.outlook.com>
 <bd95de9e-1dcc-4fbd-ba47-9d33c8bdc6fa@amd.com>
From: Tony Nguyen <anthony.l.nguyen@intel.com>
In-Reply-To: <bd95de9e-1dcc-4fbd-ba47-9d33c8bdc6fa@amd.com>
Content-Type: text/plain; charset="UTF-8"; format=flowed
Content-Transfer-Encoding: 8bit
Precedence: bulk
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?eUdBendXcm1HZFU5bUgybXJHZ2lrZG5IMEpDVFA1UW9KQjlXb3g3TWlnUlQx?=
 =?utf-8?B?SWZua1p6WGVlM1hCdzJKSUxHUHh1dTFteVRFQ2xTSHlUWWVtS3ZOcEozU1Ex?=
 =?utf-8?B?OVYxT3BSVG9CZWN5ZkU1SHZWMlJ1MnpHVUcwRDI2dzhLZXM1K2lFSXptZHgz?=
 =?utf-8?B?ejIxcEhBZ3NiV1NKZ0Z6cHh6Q2tHdnJVZWtqWFlWdkpKT2kzUWc5Qk9EM0NK?=
 =?utf-8?B?b0JGNVpjT1BjZkppK004UCs4RkhYUm5QTkFURjdWU3crbmJGNG9wK0NxVU5q?=
 =?utf-8?B?bnpIbUtFMXNKVy9OZDNFRXRzSklxM1RrNHlNekRyZDQ3NGxpSlNoSHFMNkR4?=
 =?utf-8?B?Q0xlQ0F4RGlROHVjNmxjR1RFZmxiZjV4TlcvNHlJUkd3R0FqMFBuSkw1aFhj?=
 =?utf-8?B?YzdLOEdycnRQOHd1ZVZpSU90emkzcTdKT3RZNGc3aXRxRVdyNTd1ZFJOUm9r?=
 =?utf-8?B?b3c4S0pBRzRsc2hnNDhiMStQellFTGExUDdZek5mQ3pNdzNHSHoyeU9IN2hE?=
 =?utf-8?B?QktGRWJ6cmk0blRiNlpKc0ZleFFYUVZvajkxeGw4dFBhbVlVTUdMckViWXJV?=
 =?utf-8?B?YXdOdzdoRVRoUWRpNzVXZjFwTzNVcTQ2OFBBSVhkbHBnMS84aW1BNUdFVG5t?=
 =?utf-8?B?NUNpMGo1WWZ5ZG51alVDQlBCQXVXMnpzR1JFUTE0NCt1aEJPY1E4U3BzKzk0?=
 =?utf-8?B?VVBPeHVtekR5Z0hYelMrVm1YWU9rTDlaTVNaVWtUWVNyZ2dRY1VkNk5QTHJw?=
 =?utf-8?B?czdsMWlvakFVbWp1WVdmTVd4U21jYlR2S1d6LzRQTVFCenVzTWhoVWFGek5l?=
 =?utf-8?B?WHh1Z0duektDWlRjcG5sS3Q3aTV5eXk4OEtFcWYzUHA1eGgvZUpsd2U0MmlQ?=
 =?utf-8?B?U285eUhVcUlib1JNU1ZNYUptZE5FTit3MVUxOFdqTFE0eTdGcHZjOGZPd3Ny?=
 =?utf-8?B?N0lJeHB0MFJ2NXNTZzhBU1lONTdoSXp4UjI5VlR0VnNsWURtN01ZQjIzNkdM?=
 =?utf-8?B?YkhvQ0h2N1UrSzU5RCtzUDNSa2FYS0YyMTNSZkg4ZzFhQVhOTklKenhPbE9X?=
 =?utf-8?B?SFFYdWF5ZWRoU0pXQnRVUUlRTU9xQUN0QnJqZmpuQk0yc2pKWU5WL1NPSWFU?=
 =?utf-8?B?bzd4ekRxWW4xN2RPS0tEOVRrTVhkN0htcStVSTllN0dKKzhVekNzZnhDaXF6?=
 =?utf-8?B?THljcDc4a3dEYVBKOVVYSGcwTWN4WmdwRW5oUmlUSlZpckx4NkZFK2ZmMTJP?=
 =?utf-8?B?d3Y1T0VyM0l4OHRGZkV6OHFIT3JRTTI4SXR0NVBOanJHTWVZcFg3K05DZXk1?=
 =?utf-8?B?Q3lsdzF0OVNSVU9EL0grQXh5SGxNbzRCL0UxckNhVnIxWEs4VjRubW1teDQ5?=
 =?utf-8?B?UzJITWFLalhzaC9xeVVWR1kzOTJ1RGtlMm1QYjdYWEZ6MnRaYXZQNEtTWFls?=
 =?utf-8?B?RTZjZFNVWmU5bFh3YTBLT3IxMjZTOUVZekhOUTJQZUI4Q2hhZ240ZWRiOGpO?=
 =?utf-8?B?TVZKUGN2N2hCQVVDdW9mOVBzQzE3YTFaRTBYQk5KdFJtTVVheWYxRlJRUmdx?=
 =?utf-8?B?U0dLRUhkVmlYZFJsZExnb3QvUHpocjJ3OCtsVzhiR3V5NVpHT0VMazhqeE9y?=
 =?utf-8?B?MmZXcHNaWVBaZnNTVXVKT1lBS3NHMU44SlUrUng1Mko5NXQ2RVAzZmNjNDkw?=
 =?utf-8?B?VWN5ck16UUJaMzBjMkttY1hnRENuNzZ6UFg0MDdCdUl4WVlNRFlBRm5xQjB0?=
 =?utf-8?B?OFdEV3grNEVFcGsvUWtJMjdsQjdrNjFSZUpuakwvNmxpYW9CL0VrWHBkdzFh?=
 =?utf-8?B?dWNkRVRvN21tcVB0VlRHd3VJWWhQbjM3WWxqTXB4NnIzbHp1ekNmNWdCZHR6?=
 =?utf-8?B?c0piRkszZVdqQUVJc3k1ak04SjNocTBqTUJkcXZwS01YTlpSUk1aQjNabTkx?=
 =?utf-8?B?RFRVQ1NKTjVIcmJlQSt1dmxKOTJ2T01pVHYwangyMXZ6K1laQjI2Y01MMTVO?=
 =?utf-8?B?OXJDNmRwNlVmTUwwNER2aEFxQ0pZSENPNm03Qy9JNW9DT0N6TWJrbE1yOWRo?=
 =?utf-8?B?UmV5WDU4WGJEa1VnT0paUnRRcjVRbCtwUmN2UkZVOWNPOFpkSjdjSzBlSXZ4?=
 =?utf-8?B?STJ3NTZXYms1ZzRTU3pUUFprVFhhWFZ6UkQzbHBKVEl6Rm1jaCs2QUhpQXd2?=
 =?utf-8?B?dHc9PQ==?=
X-MS-Exchange-CrossTenant-Network-Message-Id: 12504d78-23dc-4d42-ffc5-08dc01a8bcc1
X-MS-Exchange-CrossTenant-AuthSource: BL3PR11MB6435.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Dec 2023 22:12:21.4805
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: 1AXys71KWPSF8Yq3U1+CHagGj+s5Vh2LgGrEpaxnACn/vgzhsiLXfPKY9+xQe8FFiaCKsoWHkMWS9keRC7uzA+0FCA4TI5qOaSJnk9bj10o=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO1PR11MB4788
X-OriginatorOrg: intel.com


On 12/19/2023 5:32 PM, Nelson, Shannon wrote:
> On 12/17/2023 9:54 PM, Pucha, HimasekharX Reddy wrote:
>>
>>> -----Original Message-----
>>> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf 
>>> Of Kunwu Chan
>>> Subject: [Intel-wired-lan] [PATCH v5 iwl-next] i40e: Use correct 
>>> buffer size in i40e_dbg_command_read
>>>
>>> The size of "i40e_dbg_command_buf" is 256, the size of "name"
>>> depends on "IFNAMSIZ", plus a null character and format size,
>>> the total size is more than 256.
>>>
>>> Improve readability and maintainability by replacing a hardcoded string
>>> allocation and formatting by the use of the kasprintf() helper.
>>>
>>> Fixes: 02e9c290814c ("i40e: debugfs interface")
>>> Suggested-by: Simon Horman <horms@kernel.org>
>>> Suggested-by: Alexander Lobakin <aleksander.lobakin@intel.com>
>>> Suggested-by: Tony Nguyen <anthony.l.nguyen@intel.com>
>>> Cc: Kunwu Chan <kunwu.chan@hotmail.com>
>>> Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
>>> ---

...

> Much of this debugfs command code was an early driver hack that probably 
> never should have gone upstream in the form that it did.  The 
> i40e_dbg_command_buf itself was originally meant as a scratchpad to put 
> the 'last command processed', which was not really very useful, and as a 
> static global that might be written by any number of instances of i40e 
> devices, was problematic from the beginning.  Now, unless I'm mistaken, 
> it looks like nothing is writing to the buffer at all anymore, so the 
> buffer and the i40e_dbg_command_read() callback probably should just all 
> go away rather than trying to pretty up some useless code.

Thanks for the history Shannon. I'm not seeing the buffer used either 
so, I agree, we should remove it altogether.

Thanks,
Tony

> sln