Commit 79042f08 authored Jun 24, 2005 by Catalin Marinas Committed by Russell King Jun 24, 2005

[PATCH] ARM: 2698/1: Enable kernel r/w access to user pages on ARMv6



Patch from Catalin Marinas

cpu_v6_set_pte() sets the kernel access rights to r/o for user
pages (L_PTE_USER) when neither L_PTE_WRITE nor L_PTE_DIRTY are
set. This causes a kernel data abort when writing the TLS value
in the 0xffff0000 page. This patch enables the kernel r/w access.

Signed-off-by: Catalin Marinas
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

parent 5932ae3f

arch/arm/mm/proc-v6.S

+3 −3

Original line number	Diff line number	Diff line
		@@ -132,8 +132,8 @@ ENTRY(cpu_v6_switch_mm)
		* 100x 1 0 1 r/o no acc
		* 10x0 1 0 1 r/o no acc
		* 1011 0 0 1 r/w no acc
		* 110x 1 1 0 r/o r/o
		* 11x0 1 1 0 r/o r/o
		* 110x 0 1 0 r/w r/o
		* 11x0 0 1 0 r/w r/o
		* 1111 0 1 1 r/w r/w
		*/
		ENTRY(cpu_v6_set_pte)
		@@ -150,7 +150,7 @@ ENTRY(cpu_v6_set_pte)
		tst r1, #L_PTE_USER
		orrne r2, r2, #AP1 \| nG
		tstne r2, #APX
		eorne r2, r2, #AP0
		bicne r2, r2, #APX \| AP0

		tst r1, #L_PTE_YOUNG
		biceq r2, r2, #APX \| AP1 \| AP0