From 6f16f4998f98e42e3f2dedf663cfb691ff0324af Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Tue, 15 Jan 2013 18:51:32 +0100 Subject: ARM: 7628/1: head.S: map one extra section for the ATAG/DTB area We currently use a temporary 1MB section aligned to a 1MB boundary for mapping the provided device tree until the final page table is created. However, if the device tree happens to cross that 1MB boundary, the end of it remains unmapped and the kernel crashes when it attempts to access it. Given no restriction on the location of that DTB, it could end up with only a few bytes mapped at the end of a section. Solve this issue by mapping two consecutive sections. Signed-off-by: Nicolas Pitre Tested-by: Sascha Hauer Tested-by: Tomasz Figa Cc: stable@vger.kernel.org Signed-off-by: Russell King --- arch/arm/kernel/head.S | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 4eee351f466..61fcb18c7e5 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -246,6 +246,7 @@ __create_page_tables: /* * Then map boot params address in r2 if specified. + * We map 2 sections in case the ATAGs/DTB crosses a section boundary. */ mov r0, r2, lsr #SECTION_SHIFT movs r0, r0, lsl #SECTION_SHIFT @@ -253,6 +254,8 @@ __create_page_tables: addne r3, r3, #PAGE_OFFSET addne r3, r4, r3, lsr #(SECTION_SHIFT - PMD_ORDER) orrne r6, r7, r0 + strne r6, [r3], #1 << PMD_ORDER + addne r6, r6, #1 << SECTION_SHIFT strne r6, [r3] #ifdef CONFIG_DEBUG_LL -- cgit v1.2.3