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 and push it to the patch system ? Regards Santosh -- 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
