From 21d9bb4a05bac50fb4f850517af4030baecd00f6 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Thu, 7 Sep 2017 11:38:37 +0200 Subject: x86/mm: Make the SME mask a u64 The SME encryption mask is for masking 64-bit pagetable entries. It being an unsigned long works fine on X86_64 but on 32-bit builds in truncates bits leading to Xen guests crashing very early. And regardless, the whole SME mask handling shouldnt've leaked into 32-bit because SME is X86_64-only feature. So, first make the mask u64. And then, add trivial 32-bit versions of the __sme_* macros so that nothing happens there. Reported-and-tested-by: Boris Ostrovsky Tested-by: Brijesh Singh Signed-off-by: Borislav Petkov Acked-by: Tom Lendacky Acked-by: Thomas Gleixner Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Fixes: 21729f81ce8a ("x86/mm: Provide general kernel support for memory encryption") Link: http://lkml.kernel.org/r/20170907093837.76zojtkgebwtqc74@pd.tnic Signed-off-by: Ingo Molnar --- include/linux/mem_encrypt.h | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'include/linux/mem_encrypt.h') diff --git a/include/linux/mem_encrypt.h b/include/linux/mem_encrypt.h index 1255f09f5e42..265a9cd21cb4 100644 --- a/include/linux/mem_encrypt.h +++ b/include/linux/mem_encrypt.h @@ -21,7 +21,7 @@ #else /* !CONFIG_ARCH_HAS_MEM_ENCRYPT */ -#define sme_me_mask 0UL +#define sme_me_mask 0ULL #endif /* CONFIG_ARCH_HAS_MEM_ENCRYPT */ @@ -30,18 +30,23 @@ static inline bool sme_active(void) return !!sme_me_mask; } -static inline unsigned long sme_get_me_mask(void) +static inline u64 sme_get_me_mask(void) { return sme_me_mask; } +#ifdef CONFIG_AMD_MEM_ENCRYPT /* * The __sme_set() and __sme_clr() macros are useful for adding or removing * the encryption mask from a value (e.g. when dealing with pagetable * entries). */ -#define __sme_set(x) ((unsigned long)(x) | sme_me_mask) -#define __sme_clr(x) ((unsigned long)(x) & ~sme_me_mask) +#define __sme_set(x) ((x) | sme_me_mask) +#define __sme_clr(x) ((x) & ~sme_me_mask) +#else +#define __sme_set(x) (x) +#define __sme_clr(x) (x) +#endif #endif /* __ASSEMBLY__ */ -- cgit