dect
/
linux-2.6
Archived
13
0
Fork 0

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 <nico@linaro.org>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
Tested-by: Tomasz Figa <t.figa@samsung.com>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Nicolas Pitre 2013-01-15 18:51:32 +01:00 committed by Russell King
parent 568dca15aa
commit 6f16f4998f
1 changed files with 3 additions and 0 deletions

View File

@ -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