On Fri, Aug 13, 2021 at 11:59:22AM -0500, Tom Lendacky wrote:
diff --git a/arch/x86/include/asm/protected_guest.h b/arch/x86/include/asm/protected_guest.h new file mode 100644 index 000000000000..51e4eefd9542 --- /dev/null +++ b/arch/x86/include/asm/protected_guest.h @@ -0,0 +1,29 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/*
- Protected Guest (and Host) Capability checks
- Copyright (C) 2021 Advanced Micro Devices, Inc.
- Author: Tom Lendacky thomas.lendacky@amd.com
- */
+#ifndef _X86_PROTECTED_GUEST_H +#define _X86_PROTECTED_GUEST_H
+#include <linux/mem_encrypt.h>
+#ifndef __ASSEMBLY__
+static inline bool prot_guest_has(unsigned int attr) +{ +#ifdef CONFIG_AMD_MEM_ENCRYPT
- if (sme_me_mask)
return amd_prot_guest_has(attr);+#endif
- return false;
+}
+#endif /* __ASSEMBLY__ */
+#endif /* _X86_PROTECTED_GUEST_H */
I think this can be simplified more, diff ontop below:
- no need for the ifdeffery as amd_prot_guest_has() has versions for both when CONFIG_AMD_MEM_ENCRYPT is set or not.
- the sme_me_mask check is pushed there too.
- and since this is vendor-specific, I'm checking the vendor bit. Yeah, yeah, cross-vendor but I don't really believe that.
--- diff --git a/arch/x86/include/asm/protected_guest.h b/arch/x86/include/asm/protected_guest.h index 51e4eefd9542..8541c76d5da4 100644 --- a/arch/x86/include/asm/protected_guest.h +++ b/arch/x86/include/asm/protected_guest.h @@ -12,18 +12,13 @@
#include <linux/mem_encrypt.h>
-#ifndef __ASSEMBLY__ - static inline bool prot_guest_has(unsigned int attr) { -#ifdef CONFIG_AMD_MEM_ENCRYPT - if (sme_me_mask) + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD || + boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) return amd_prot_guest_has(attr); -#endif
return false; }
-#endif /* __ASSEMBLY__ */ - #endif /* _X86_PROTECTED_GUEST_H */ diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index edc67ddf065d..5a0442a6f072 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -392,6 +392,9 @@ bool noinstr sev_es_active(void)
bool amd_prot_guest_has(unsigned int attr) { + if (!sme_me_mask) + return false; + switch (attr) { case PATTR_MEM_ENCRYPT: return sme_me_mask != 0;