[PATCH 3.13 043/151] arm64: Make DMA coherent and strongly ordered mappings not executable

Kamal Mostafa kamal at canonical.com
Fri May 2 15:37:11 UTC 2014


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

------------------

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

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 at arm.com>
Reported-by: Bharat Bhushan <Bharat.Bhushan at freescale.com>
Tested-by: Laura Abbott <lauraa at codeaurora.org>
Tested-by: Bharat Bhushan <Bharat.Bhushan at freescale.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 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 2c121f7..a08be42 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,
-- 
1.9.1





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