-----Original Message-----
From: Catalin Marinas [mailto:catalin.marinas at arm.com]
Sent: Wednesday, September 29, 2010 8:21 PM
To: Shilimkar, Santosh
Cc: linux-omap at vger.kernel.org; linux-arm-kernel at lists.infradead.org
Subject: Re: [PATCH 01/14] ARM: mmu: Setup MT_MEMORY and
MT_MEMORY_NONCACHED L1 entries

Hi Santosh,

Santosh Shilimkar [off-list ref] wrote:

quoted

This patch populates the L1 entries for MT_MEMORY and

MT_MEMORY_NONCACHED

quoted

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 <redacted>
Reviewed-by: Russell King <redacted>
---
 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?

I think you are right. It should have "L_PTE_WRITE" as well.

Regards,
Santosh