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| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2022-04-06 02:29:13 +0300 |
|---|---|---|
| committer | Dave Hansen <dave.hansen@linux.intel.com> | 2022-04-07 18:27:50 +0300 |
| commit | 41394e33f3a0ce791caf0e086e1fca850832ddec (patch) | |
| tree | 0aa0b1d188e8af08b4802449060688a10bbf6e0c /arch/x86/coco/core.c | |
| parent | eb94f1b6a70a683040d60d21bbb6ad65f082600a (diff) | |
| download | linux-41394e33f3a0ce791caf0e086e1fca850832ddec.tar.xz | |
x86/tdx: Extend the confidential computing API to support TDX guests
Confidential Computing (CC) features (like string I/O unroll support,
memory encryption/decryption support, etc) are conditionally enabled
in the kernel using cc_platform_has() API. Since TDX guests also need
to use these CC features, extend cc_platform_has() API and add TDX
guest-specific CC attributes support.
CC API also provides an interface to deal with encryption mask. Extend
it to cover TDX.
Details about which bit in the page table entry to be used to indicate
shared/private state is determined by using the TDINFO TDCALL.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20220405232939.73860-5-kirill.shutemov@linux.intel.com
Diffstat (limited to 'arch/x86/coco/core.c')
| -rw-r--r-- | arch/x86/coco/core.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/coco/core.c b/arch/x86/coco/core.c index fc1365dd927e..3f3008783e05 100644 --- a/arch/x86/coco/core.c +++ b/arch/x86/coco/core.c @@ -87,9 +87,18 @@ EXPORT_SYMBOL_GPL(cc_platform_has); u64 cc_mkenc(u64 val) { + /* + * Both AMD and Intel use a bit in the page table to indicate + * encryption status of the page. + * + * - for AMD, bit *set* means the page is encrypted + * - for Intel *clear* means encrypted. + */ switch (vendor) { case CC_VENDOR_AMD: return val | cc_mask; + case CC_VENDOR_INTEL: + return val & ~cc_mask; default: return val; } @@ -97,9 +106,12 @@ u64 cc_mkenc(u64 val) u64 cc_mkdec(u64 val) { + /* See comment in cc_mkenc() */ switch (vendor) { case CC_VENDOR_AMD: return val & ~cc_mask; + case CC_VENDOR_INTEL: + return val | cc_mask; default: return val; } |