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Date: Thu, 20 Jun 2013 16:16:40 +0800
From: Chen Gang <gang.chen@asianux.com>
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To: Thomas Gleixner <tglx@linutronix.de>
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Subject: Re: [PATCH] kernel/itimer.c: for return value, using -EINVAL instead
 of -EFAULT
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On 06/20/2013 03:44 PM, Thomas Gleixner wrote:
> We could do that, but that makes no sense. If we can detect it before
> copy_to_user() we can return the exactly same return value which we
> would return via copy_to_user(). That avoids to take a trap and run
> through the fixup code

I don't think "that makes no sense".

In most cases, the 'value' will not be NULL, so it is better for
performance (save one compare instruction, at least).

Also, it will make the code simpler and clearer for readers.



Thanks.
-- 
Chen Gang

Asianux Corporation