linux-kernel - RE: [PATCH] sysfs: Remove page boundary align limitation on sysfs_emit and sysfs_emit

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Message-ID: <DM6PR12MB4250080A69BD3E2DB0050273FBD49@DM6PR12MB4250.namprd12.prod.outlook.com>
Date:   Wed, 8 Sep 2021 13:21:16 +0000
From:   "Yu, Lang" <Lang.Yu@....com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>
CC:     Joe Perches <joe@...ches.com>,
        "Rafael J . Wysocki" <rafael@...nel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH] sysfs: Remove page boundary align limitation on
 sysfs_emit and sysfs_emit_at

[AMD Official Use Only]



>-----Original Message-----
>From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
>Sent: Wednesday, September 8, 2021 9:04 PM
>To: Yu, Lang <Lang.Yu@....com>
>Cc: Joe Perches <joe@...ches.com>; Rafael J . Wysocki <rafael@...nel.org>;
>linux-kernel@...r.kernel.org
>Subject: Re: [PATCH] sysfs: Remove page boundary align limitation on sysfs_emit
>and sysfs_emit_at
>
>A:
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>A: Because it messes up the order in which people normally read text.
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>
>A: No.
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>
>On Wed, Sep 08, 2021 at 12:52:43PM +0000, Yu, Lang wrote:
>> [AMD Official Use Only]
>>
>> Thanks for your reply.
>> Just curious if we don't put such a limitation, what are the consequences?
>> If we remove the limitation, sys_emit/sys_emit_at api will be more flexible.
>> Since the comments of  sysfs_emit/ sys_emit_at api are " sysfs_emit -
>> scnprintf equivalent, aware of PAGE_SIZE buffer. ", Why not make them
>> more equivalent with scnprintf?
>
>Because this is not a general replacement for scnprintf(), it is only to be used with
>sysfs files.
>
>Where else are you wanting to use these functions that this patch woulud be
>required that does not haver to deal with sysfs?
>
>thanks,
>
>greg k-h

But some guys think it is a general replacement for scnprintf(),
and  recommend that use sysfs_emit() instead of scnprintf(),
and send many patches that replace  scnprintf() with sysfs_emit(),
and finally cause some invalid sysfs_emit_at: buf:00000000f19bdfde warnings.
 
I think we better not put " scnprintf equivalent, aware of PAGE_SIZE buffer " words in comments.
It is obviously not. Some  guys are misled by that. Thanks! 

Regards,
Lang