On Wed, Sep 29, 2010 at 03:51:21PM +0100, Catalin Marinas wrote:
> Hi Santosh,
>
> Santosh Shilimkar <santosh.shilimkar@xxxxxx> wrote:
> > This patch populates the L1 entries for MT_MEMORY and MT_MEMORY_NONCACHED
> > types so that at boot-up, we can map memories outside system memory
> > at page level granularity
> >
> > Previously the mapping was limiting to section level, which creates
> > unnecessary addiotional mapping for which physical memory may not
> > present. On the newer ARM with speculation, this is dangerous and can
> > result in untraceable aborts.
> >
> > Signed-off-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
> > Reviewed-by: Russell King <linux@xxxxxxxxxxxxxxxx>
> > ---
> > arch/arm/mm/mmu.c | 17 +++++++++++++++--
> > 1 files changed, 15 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
> > index 6e1c4f6..3e986a6 100644
> > --- a/arch/arm/mm/mmu.c
> > +++ b/arch/arm/mm/mmu.c
> > @@ -246,6 +246,9 @@ static struct mem_type mem_types[] = {
> > .domain = DOMAIN_USER,
> > },
> > [MT_MEMORY] = {
> > + .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
> > + L_PTE_USER | L_PTE_EXEC,
> > + .prot_l1 = PMD_TYPE_TABLE,
>
> Just a quick question - does this need to have L_PTE_USER? Is it
> read-only or it needs L_PTE_WRITE as well?
Eek. It should not have L_PTE_USER or else it will be accessible to
userspace.
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