On Sat, Apr 26, 2008 at 04:31:32PM +0800, WANG Cong wrote:
quoted text
> > +		rem = copy_to_user(buf, &data->contents[off], count);
> > +		*ppos += count - rem;
> > +		if (rem > 0)
> > +			return -EFAULT;
> 
> Could you please explain why check 'rem' after using it here?

Actually, this isn't as wrong as it looks. copy_to_user returns what
hasn't been copied (rem == remaining).  So, I think the mistake is to
return -EFAULT here.  Returning the short count would be right, unless
rem == count, in which case we return -EFAULT.

       	      	 Jeff

-- 
Work email - jdike at linux dot intel dot com
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