Re: [PATCH] Fix kunmap_atomic's use of kpte_clear_flush()

[Jeremy Fitzhardinge]

Rusty Russell wrote:
> On Tue, 2006-11-07 at 16:22 -0800, Jeremy Fitzhardinge wrote:
>   
> > kunmap_atomic() will call kpte_clear_flush with vaddr/ptep arguments
> > which don't correspond if the vaddr is just a normal lowmem address
> > (ie, not in the KMAP area).  This patch makes sure that the pte is
> > only cleared if kmap area was actually used for the mapping.
> >     
>
> Or in other words, if kmap_atomic() does nothing, kunmap_atomic() should
> do nothing.
>   

Sure.  I guess there's no particular reason why kmap_atomic() couldn't 
always map, but I guess avoid the pagetable updates is worthwhile.

   J
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/