Re: [PATCH v2 05/20] ARM: LPAE: Introduce L_PTE_NOEXEC andL_PTE_NOWRITE
From: Russell King - ARM Linux
Date: Wed Nov 17 2010 - 12:16:43 EST
On Wed, Nov 17, 2010 at 05:02:37PM +0000, Catalin Marinas wrote:
> On 15 November 2010 18:30, Russell King - ARM Linux
> <linux@xxxxxxxxxxxxxxxx> wrote:
> > On Fri, Nov 12, 2010 at 06:00:25PM +0000, Catalin Marinas wrote:
> >> --- a/arch/arm/include/asm/pgtable-2level.h
> >> +++ b/arch/arm/include/asm/pgtable-2level.h
> >> @@ -128,6 +128,8 @@
> >> #define L_PTE_USER (1 << 8)
> >> #define L_PTE_EXEC (1 << 9)
> >> #define L_PTE_SHARED (1 << 10) /* shared(v6), coherent(xsc3) */
> >> +#define L_PTE_NOEXEC (0)
> >> +#define L_PTE_NOWRITE (0)
> >
> > Let's not make this more complicated than it has to be. If we need the
> > inverse of WRITE and EXEC, then that's what we should change everyone to,
> > not invent a new system to work along side the old system.
>
> Question on the pgprot_noncached/writecombine/dmacoherent - in the
> current implementation we pass L_PTE_EXEC on the dmacoherent macro.
Erm. Please look at the code again.
--
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/