[tip:,x86/sev] x86/mm: Fix memory encryption features advertisement
Commit Message
The following commit has been merged into the x86/sev branch of tip:
Commit-ID: 4cab62c058f5a150d9960c112362e5c76d204d9d
Gitweb: https://git.kernel.org/tip/4cab62c058f5a150d9960c112362e5c76d204d9d
Author: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
AuthorDate: Wed, 24 Jan 2024 16:02:16 +02:00
Committer: Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Mon, 29 Jan 2024 17:08:27 +01:00
x86/mm: Fix memory encryption features advertisement
When memory encryption is enabled, the kernel prints the encryption
flavor that the system supports.
The check assumes that everything is AMD SME/SEV if it doesn't have
the TDX CPU feature set.
Hyper-V vTOM sets cc_vendor to CC_VENDOR_INTEL when it runs as L2 guest
on top of TDX, but not X86_FEATURE_TDX_GUEST. Hyper-V only needs memory
encryption enabled for I/O without the rest of CoCo enabling.
To avoid confusion, check the cc_vendor directly.
[ bp: Massage commit message. ]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Jeremi Piotrowski <jpiotrowski@linux.microsoft.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Acked-by: Kai Huang <kai.huang@intel.com>
Link: https://lore.kernel.org/r/20240124140217.533748-1-kirill.shutemov@linux.intel.com
---
arch/x86/mm/mem_encrypt.c | 56 ++++++++++++++++++++------------------
1 file changed, 30 insertions(+), 26 deletions(-)
@@ -42,38 +42,42 @@ bool force_dma_unencrypted(struct device *dev)
static void print_mem_encrypt_feature_info(void)
{
- pr_info("Memory Encryption Features active:");
+ pr_info("Memory Encryption Features active: ");
- if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST)) {
- pr_cont(" Intel TDX\n");
- return;
- }
-
- pr_cont(" AMD");
+ switch (cc_vendor) {
+ case CC_VENDOR_INTEL:
+ pr_cont("Intel TDX\n");
+ break;
+ case CC_VENDOR_AMD:
+ pr_cont("AMD");
- /* Secure Memory Encryption */
- if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) {
+ /* Secure Memory Encryption */
+ if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) {
/*
* SME is mutually exclusive with any of the SEV
* features below.
- */
- pr_cont(" SME\n");
- return;
+ */
+ pr_cont(" SME\n");
+ return;
+ }
+
+ /* Secure Encrypted Virtualization */
+ if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
+ pr_cont(" SEV");
+
+ /* Encrypted Register State */
+ if (cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
+ pr_cont(" SEV-ES");
+
+ /* Secure Nested Paging */
+ if (cc_platform_has(CC_ATTR_GUEST_SEV_SNP))
+ pr_cont(" SEV-SNP");
+
+ pr_cont("\n");
+ break;
+ default:
+ pr_cont("Unknown\n");
}
-
- /* Secure Encrypted Virtualization */
- if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
- pr_cont(" SEV");
-
- /* Encrypted Register State */
- if (cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
- pr_cont(" SEV-ES");
-
- /* Secure Nested Paging */
- if (cc_platform_has(CC_ATTR_GUEST_SEV_SNP))
- pr_cont(" SEV-SNP");
-
- pr_cont("\n");
}
/* Architecture __weak replacement functions */