Re: [PATCH 1/2] Introduce copy_user_handle_tail routine

[Andi Kleen]

On Mon, Jul 07, 2008 at 02:12:56PM +0200, Vitaly Mayatskikh wrote:
> Vitaly Mayatskikh <v.mayatskih@xxxxxxxxx> writes:
> 
> >> one), by limiting the byte-for-byte one to be within a page, but that 
> >> would be a "future enhancement" thing.
> >
> > Btw, how much does it cost to CPU to do a fault? Can it be compared with
> > average time of find_vma()?
> 
> Remark: this is for preventing fault in memset, not byte-to-byte copy.

memset never faults.

The current code doesn't handle it and it never happened.

-Andi
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