Commit 7c302cfb authored by Joey Gouly's avatar Joey Gouly Committed by Catalin Marinas
Browse files

arm64: add PTE_WRITE to PROT_SECT_NORMAL 



With PIE enabled, PROT_SECT_NORMAL would map onto PAGE_KERNEL_RO.
Add PTE_WRITE so that this maps onto PAGE_KERNEL, so that it is writable.

Without PIE, this should enable DBM for PROT_SECT_NORMAL. However PTE_RDONLY
is already cleared, so the DBM mechanism is not used, and it is always writable,
so this is functionally equivalent.

Signed-off-by: default avatarJoey Gouly <joey.gouly@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20230606145859.697944-13-joey.gouly@arm.com


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent f0af339f

arch/arm64/include/asm/pgtable-prot.h

+1 −1
Original line number Diff line number Diff line
@@ -60,7 +60,7 @@ extern bool arm64_use_ng_mappings; 
#define PROT_NORMAL_TAGGED	(PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_TAGGED))



#define PROT_SECT_DEVICE_nGnRE	(PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_DEVICE_nGnRE))

#define PROT_SECT_NORMAL	(PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))

#define PROT_SECT_NORMAL	(PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PTE_WRITE | PMD_ATTRINDX(MT_NORMAL))

#define PROT_SECT_NORMAL_EXEC	(PROT_SECT_DEFAULT | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))



#define _PAGE_DEFAULT		(_PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL))