From: Li Yang Date: Fri, 7 May 2010 08:38:34 +0000 (+0800) Subject: powerpc/fsl-booke: Fix InstructionTLBError execute permission check X-Git-Tag: accepted/tizen/common/20141203.182822~11137^2~8^2~1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=fa6bd996db2fbecd7a9a408c158105c55a51fe41;p=platform%2Fkernel%2Flinux-arm64.git powerpc/fsl-booke: Fix InstructionTLBError execute permission check In CONFIG_PTE_64BIT the PTE format has unique permission bits for user and supervisor execute. However on !CONFIG_PTE_64BIT we overload the supervisor bit to imply user execute with _PAGE_USER set. This allows us to use the same permission check mask for user or supervisor code on !CONFIG_PTE_64BIT. However, on CONFIG_PTE_64BIT we map _PAGE_EXEC to _PAGE_BAP_UX so we need a different permission mask based on the fault coming from a kernel address or user space. Without unique permission masks we see issues like the following with modules: 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 Signed-off-by: Jin Qing Signed-off-by: Kumar Gala --- diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S index 7255265..edd4a57 100644 --- a/arch/powerpc/kernel/head_fsl_booke.S +++ b/arch/powerpc/kernel/head_fsl_booke.S @@ -639,6 +639,13 @@ 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@h +#else + li r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC +#endif b 4f /* Get the PGD for the current thread */ @@ -646,15 +653,15 @@ 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@h #else li r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC #endif +4: FIND_PTE andc. r13,r13,r11 /* Check permission */