On Tue, May 08, 2012 at 03:20:43PM +0100, Santosh Shilimkar wrote: > On Tuesday 08 May 2012 07:46 PM, Catalin Marinas wrote: > > On Tue, May 08, 2012 at 03:01:57PM +0100, Shilimkar, Santosh wrote: > >> From b906ef372f0e2dfa7e1fbc3c87406b1c303d8975 Mon Sep 17 00:00:00 2001 > >> From: R Sricharan <r.sricharan@xxxxxx> > >> Date: Mon, 7 May 2012 15:11:58 +0530 > >> Subject: [PATCH] ARM: decompressor: Fix mmu mapping for non-DRAM address > >> space. > >> > >> ARM decompressor code setups entire 4GB address space pages. > >> Out of the 4GB, about 256MB are setup with normal memory attributes > >> for needed DRAM and the rest of the address space as Strongly ordered. > >> > >> But since all the sections are mapped in DOMAIN0(Manager), processor > >> like Cortex-A15, can speculatively prefetch from non-DRAM read sensitive > >> areas even in the presence of XN(Non-executable). This is because XN > >> attribute is ignored when domain is Manager. > >> > >> This can lead to accesses to non-accessible address regions leading > >> to various interconnect violations. The issue is observed on OMAP5. > >> > >> This patch tries to fix the issue by ensuring that all regions > >> are marked as a client domain so that XN attribute is effective. > >> > >> Signed-off-by: R Sricharan <r.sricharan@xxxxxx> > >> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx> > >> Cc: Russell King <linux@xxxxxxxxxxxxxxxx> > >> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> > >> --- > >> arch/arm/boot/compressed/head.S | 10 ++++++++-- > >> 1 files changed, 8 insertions(+), 2 deletions(-) > >> > >> diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S > >> index dc7e8ce..a2602b8 100644 > >> --- a/arch/arm/boot/compressed/head.S > >> +++ b/arch/arm/boot/compressed/head.S > >> @@ -578,10 +578,12 @@ __setup_mmu: sub r3, r4, #16384 @ Page directory size > >> mov r9, r0, lsr #18 > >> mov r9, r9, lsl #18 @ start of RAM > >> add r10, r9, #0x10000000 @ a reasonable RAM size > >> - mov r1, #0x12 > >> + mov r1, #0x02 @ Default executable section > > > > I think it is simpler if you leave the original code here (with XN) > > Sounds good. With that updated can I add your ack Yes. > and push it to the patch system ? That's up to Russell. -- Catalin -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
