PAGE_HYP_DEVICE is intended to encode attribute bits for an EL2 stage-1 pte mapping a device. Unfortunately, it includes PROT_DEVICE_nGnRE which encodes attributes for EL1 stage-1 mappings such as UXN and nG, which are RES0 for EL2, and DBM which is meaningless as TCR_EL2.HD is not set.
Fix the definition of PAGE_HYP_DEVICE so that it doesn't set RES0 bits at EL2.
Cc: Marc Zyngier maz@kernel.org Cc: Catalin Marinas catalin.marinas@arm.com Cc: James Morse james.morse@arm.com Cc: stable@vger.kernel.org Signed-off-by: Will Deacon will@kernel.org --- Marc -- I'm happy to take this as a fix via arm64 with your Ack. Please just let me know.
arch/arm64/include/asm/pgtable-prot.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index 2e7e0f452301..4d867c6446c4 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -67,7 +67,7 @@ extern bool arm64_use_ng_mappings; #define PAGE_HYP __pgprot(_HYP_PAGE_DEFAULT | PTE_HYP | PTE_HYP_XN) #define PAGE_HYP_EXEC __pgprot(_HYP_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY) #define PAGE_HYP_RO __pgprot(_HYP_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY | PTE_HYP_XN) -#define PAGE_HYP_DEVICE __pgprot(PROT_DEVICE_nGnRE | PTE_HYP) +#define PAGE_HYP_DEVICE __pgprot(_PROT_DEFAULT | PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_HYP | PTE_HYP_XN)
#define PAGE_S2_MEMATTR(attr) \ ({ \
On 2020-07-08 17:25, Will Deacon wrote:
PAGE_HYP_DEVICE is intended to encode attribute bits for an EL2 stage-1 pte mapping a device. Unfortunately, it includes PROT_DEVICE_nGnRE which encodes attributes for EL1 stage-1 mappings such as UXN and nG, which are RES0 for EL2, and DBM which is meaningless as TCR_EL2.HD is not set.
Fix the definition of PAGE_HYP_DEVICE so that it doesn't set RES0 bits at EL2.
Cc: Marc Zyngier maz@kernel.org Cc: Catalin Marinas catalin.marinas@arm.com Cc: James Morse james.morse@arm.com Cc: stable@vger.kernel.org Signed-off-by: Will Deacon will@kernel.org
Marc -- I'm happy to take this as a fix via arm64 with your Ack. Please just let me know.
arch/arm64/include/asm/pgtable-prot.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
Acked-by: Marc Zyngier maz@kernel.org
Thanks for fixing this!
M.
On Wed, 8 Jul 2020 17:25:46 +0100, Will Deacon wrote:
PAGE_HYP_DEVICE is intended to encode attribute bits for an EL2 stage-1 pte mapping a device. Unfortunately, it includes PROT_DEVICE_nGnRE which encodes attributes for EL1 stage-1 mappings such as UXN and nG, which are RES0 for EL2, and DBM which is meaningless as TCR_EL2.HD is not set.
Fix the definition of PAGE_HYP_DEVICE so that it doesn't set RES0 bits at EL2.
Applied to arm64 (for-next/fixes), thanks!
[1/1] KVM: arm64: Fix definition of PAGE_HYP_DEVICE https://git.kernel.org/arm64/c/68cf617309b5
Cheers,
linux-stable-mirror@lists.linaro.org