diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2018-04-25 17:58:20 +0100 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2018-07-09 11:37:42 +0100 |
| commit | 2f6ea23f63cca99cd514c221f075c986b57c927e (patch) | |
| tree | 23f3397f81f925209b318a6df577a58fa529ba47 /arch | |
| parent | 09605e94c2cbb67c6472c07e1c06a7a0e7271f83 (diff) | |
arm64: KVM: Avoid marking pages as XN in Stage-2 if CTR_EL0.DIC is set
On systems where CTR_EL0.DIC is set, we don't need to perform
icache invalidation to guarantee that we'll fetch the right
instruction stream.
This also means that taking a permission fault to invalidate the
icache is an unnecessary overhead.
On such systems, we can safely leave the page as being executable.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/include/asm/pgtable-prot.h | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index c66c3047400e..78b942c1bea4 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -77,8 +77,18 @@ __val; \ }) -#define PAGE_S2 __pgprot(_PROT_DEFAULT | PAGE_S2_MEMATTR(NORMAL) | PTE_S2_RDONLY | PTE_S2_XN) -#define PAGE_S2_DEVICE __pgprot(_PROT_DEFAULT | PAGE_S2_MEMATTR(DEVICE_nGnRE) | PTE_S2_RDONLY | PTE_S2_XN) +#define PAGE_S2_XN \ + ({ \ + u64 __val; \ + if (cpus_have_const_cap(ARM64_HAS_CACHE_DIC)) \ + __val = 0; \ + else \ + __val = PTE_S2_XN; \ + __val; \ + }) + +#define PAGE_S2 __pgprot(_PROT_DEFAULT | PAGE_S2_MEMATTR(NORMAL) | PTE_S2_RDONLY | PAGE_S2_XN) +#define PAGE_S2_DEVICE __pgprot(_PROT_DEFAULT | PAGE_S2_MEMATTR(DEVICE_nGnRE) | PTE_S2_RDONLY | PAGE_S2_XN) #define PAGE_NONE __pgprot(((_PAGE_DEFAULT) & ~PTE_VALID) | PTE_PROT_NONE | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN) #define PAGE_SHARED __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE) |