[PATCH] pte_fsl_booke: fix instruction TLB error permission check

Li Yang leoli at freescale.com
Fri May 7 18:38:34 EST 2010


Check the user/supervisor execution permission base on the code address.
This fixes the following oops on module loading or removing.

Unable to handle kernel paging request for instruction fetch
Faulting instruction address: 0xf938d040
Oops: Kernel access of bad area, sig: 11 [#1]

Signed-off-by: Li Yang <leoli at freescale.com>
Signed-off-by: Jin Qing <b24347 at freescale.com>
---
 arch/powerpc/kernel/head_fsl_booke.S |   13 ++++++++++---
 1 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index 78aac7b..61b6687 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -684,6 +684,13 @@ interrupt_base:
 	rlwinm	r12,r12,0,16,1
 	mtspr	SPRN_MAS1,r12
 
+	/* Make up the required permissions for kernel code */
+#ifdef CONFIG_PTE_64BIT
+	li	r13,_PAGE_PRESENT | _PAGE_BAP_SX
+	oris	r13,r13,_PAGE_ACCESSED at h
+#else
+	li	r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
+#endif
 	b	4f
 
 	/* Get the PGD for the current thread */
@@ -691,15 +698,15 @@ interrupt_base:
 	mfspr	r11,SPRN_SPRG_THREAD
 	lwz	r11,PGDIR(r11)
 
-4:
-	/* Make up the required permissions */
+	/* Make up the required permissions for user code */
 #ifdef CONFIG_PTE_64BIT
-	li	r13,_PAGE_PRESENT | _PAGE_EXEC
+	li	r13,_PAGE_PRESENT | _PAGE_BAP_UX
 	oris	r13,r13,_PAGE_ACCESSED at h
 #else
 	li	r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
 #endif
 
+4:
 	FIND_PTE
 	andc.	r13,r13,r11		/* Check permission */
 
-- 
1.6.6-rc1.GIT



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