[PATCH 3.12 007/182] arm64: Make DMA coherent and strongly ordered mappings not executable

Jiri Slaby
2014-05-13T10:40:22Z

From: Catalin Marinas <catalin.marinas@arm.com>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit de2db7432917a82b62d55bb59635586eeca6d1bd upstream.

pgprot_{dmacoherent,writecombine,noncached} don't need to generate
executable mappings with side-effects like __sync_icache_dcache() being
called when the mapping is in user space.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Tested-by: Laura Abbott <lauraa@codeaurora.org>
Tested-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
arch/arm64/include/asm/pgtable.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 62713586d6e3..05fe332c1061 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -253,11 +253,11 @@ static inline int has_transparent_hugepage(void)
* Mark the prot value as uncacheable and unbufferable.
*/
#define pgprot_noncached(prot) \
- __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE))
+ __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
#define pgprot_writecombine(prot) \
- __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC))
+ __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
#define pgprot_dmacoherent(prot) \
- __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC))
+ __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
#define __HAVE_PHYS_MEM_ACCESS_PROT
struct file;
extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
--
1.9.3