From: Arvind Sankar nivedita@alum.mit.edu
commit 29ac40cbed2bc06fa218ca25d7f5e280d3d08a25 upstream.
The PAT bit is in different locations for 4k and 2M/1G page table entries.
Add a definition for _PAGE_LARGE_CACHE_MASK to represent the three caching bits (PWT, PCD, PAT), similar to _PAGE_CACHE_MASK for 4k pages, and use it in the definition of PMD_FLAGS_DEC_WP to get the correct PAT index for write-protected pages.
Fixes: 6ebcb060713f ("x86/mm: Add support to encrypt the kernel in-place") Signed-off-by: Arvind Sankar nivedita@alum.mit.edu Signed-off-by: Borislav Petkov bp@suse.de Tested-by: Tom Lendacky thomas.lendacky@amd.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20201111160946.147341-1-nivedita@alum.mit.edu Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/include/asm/pgtable_types.h | 1 + arch/x86/mm/mem_encrypt_identity.c | 4 ++-- 2 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index 71ea49e7db74..02806d95ad6e 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -148,6 +148,7 @@ enum page_cache_mode { #endif
#define _PAGE_CACHE_MASK (_PAGE_PAT | _PAGE_PCD | _PAGE_PWT) +#define _PAGE_LARGE_CACHE_MASK (_PAGE_PWT | _PAGE_PCD | _PAGE_PAT_LARGE) #define _PAGE_NOCACHE (cachemode2protval(_PAGE_CACHE_MODE_UC)) #define _PAGE_CACHE_WP (cachemode2protval(_PAGE_CACHE_MODE_WP))
diff --git a/arch/x86/mm/mem_encrypt_identity.c b/arch/x86/mm/mem_encrypt_identity.c index c9faf34cbb62..1f25201de0af 100644 --- a/arch/x86/mm/mem_encrypt_identity.c +++ b/arch/x86/mm/mem_encrypt_identity.c @@ -47,8 +47,8 @@ #define PMD_FLAGS_LARGE (__PAGE_KERNEL_LARGE_EXEC & ~_PAGE_GLOBAL)
#define PMD_FLAGS_DEC PMD_FLAGS_LARGE -#define PMD_FLAGS_DEC_WP ((PMD_FLAGS_DEC & ~_PAGE_CACHE_MASK) | \ - (_PAGE_PAT | _PAGE_PWT)) +#define PMD_FLAGS_DEC_WP ((PMD_FLAGS_DEC & ~_PAGE_LARGE_CACHE_MASK) | \ + (_PAGE_PAT_LARGE | _PAGE_PWT))
#define PMD_FLAGS_ENC (PMD_FLAGS_LARGE | _PAGE_ENC)