The following commit has been merged into the x86/cc branch of tip:
Commit-ID: 655a0fa34b4f7ac6e2b1406fab15e52a7b6accb1
Gitweb: https://git.kernel.org/tip/655a0fa34b4f7ac6e2b1406fab15e52a7b6accb1
Author: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
AuthorDate: Tue, 22 Feb 2022 21:57:39 +03:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Wed, 23 Feb 2022 19:14:16 +01:00
x86/coco: Explicitly declare type of confidential computing platform
The kernel derives the confidential computing platform
type it is running as from sme_me_mask on AMD or by using
hv_is_isolation_supported() on HyperV isolation VMs. This detection
process will be more complicated as more platforms get added.
Declare a confidential computing vendor variable explicitly and set it
via cc_set_vendor() on the respective platform.
[ bp: Massage commit message, fixup HyperV check. ]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
Link: https://lore.kernel.org/r/20220222185740.26228-4-kirill.shutemov@xxxxxxxxxxxxxxx
---
arch/x86/coco/core.c | 29 +++++++++++++++++------------
arch/x86/include/asm/coco.h | 14 ++++++++++++++-
arch/x86/kernel/cpu/mshyperv.c | 6 ++++++-
arch/x86/mm/mem_encrypt_identity.c | 11 +++++++----
4 files changed, 44 insertions(+), 16 deletions(-)
create mode 100644 arch/x86/include/asm/coco.h
diff --git a/arch/x86/coco/core.c b/arch/x86/coco/core.c
index 6a6ffcd..476dcd1 100644
--- a/arch/x86/coco/core.c
+++ b/arch/x86/coco/core.c
@@ -9,18 +9,15 @@
#include <linux/export.h>
#include <linux/cc_platform.h>
-#include <linux/mem_encrypt.h>
-#include <asm/mshyperv.h>
+#include <asm/coco.h>
#include <asm/processor.h>
-static bool __maybe_unused intel_cc_platform_has(enum cc_attr attr)
+static enum cc_vendor vendor __ro_after_init;
+
+static bool intel_cc_platform_has(enum cc_attr attr)
{
-#ifdef CONFIG_INTEL_TDX_GUEST
- return false;
-#else
return false;
-#endif
}
/*
@@ -74,12 +71,20 @@ static bool hyperv_cc_platform_has(enum cc_attr attr)
bool cc_platform_has(enum cc_attr attr)
{
- if (sme_me_mask)
+ switch (vendor) {
+ case CC_VENDOR_AMD:
return amd_cc_platform_has(attr);
-
- if (hv_is_isolation_supported())
+ case CC_VENDOR_INTEL:
+ return intel_cc_platform_has(attr);
+ case CC_VENDOR_HYPERV:
return hyperv_cc_platform_has(attr);
-
- return false;
+ default:
+ return false;
+ }
}
EXPORT_SYMBOL_GPL(cc_platform_has);
+
+__init void cc_set_vendor(enum cc_vendor v)
+{
+ vendor = v;
+}
diff --git a/arch/x86/include/asm/coco.h b/arch/x86/include/asm/coco.h
new file mode 100644
index 0000000..e49f9dd
--- /dev/null
+++ b/arch/x86/include/asm/coco.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_COCO_H
+#define _ASM_X86_COCO_H
+
+enum cc_vendor {
+ CC_VENDOR_NONE,
+ CC_VENDOR_AMD,
+ CC_VENDOR_HYPERV,
+ CC_VENDOR_INTEL,
+};
+
+void cc_set_vendor(enum cc_vendor v);
+
+#endif /* _ASM_X86_COCO_H */
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 5a99f99..e0a5724 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -33,6 +33,7 @@
#include <asm/nmi.h>
#include <clocksource/hyperv_timer.h>
#include <asm/numa.h>
+#include <asm/coco.h>
/* Is Linux running as the root partition? */
bool hv_root_partition;
@@ -344,6 +345,11 @@ static void __init ms_hyperv_init_platform(void)
*/
swiotlb_force = SWIOTLB_FORCE;
#endif
+ /* Isolation VMs are unenlightened SEV-based VMs, thus this check: */
+ if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) {
+ if (hv_get_isolation_type() != HV_ISOLATION_TYPE_NONE)
+ cc_set_vendor(CC_VENDOR_HYPERV);
+ }
}
if (hv_max_functions_eax >= HYPERV_CPUID_NESTED_FEATURES) {
diff --git a/arch/x86/mm/mem_encrypt_identity.c b/arch/x86/mm/mem_encrypt_identity.c
index 3f0abb4..06314ae 100644
--- a/arch/x86/mm/mem_encrypt_identity.c
+++ b/arch/x86/mm/mem_encrypt_identity.c
@@ -44,6 +44,7 @@
#include <asm/setup.h>
#include <asm/sections.h>
#include <asm/cmdline.h>
+#include <asm/coco.h>
#include "mm_internal.h"
@@ -565,8 +566,7 @@ void __init sme_enable(struct boot_params *bp)
} else {
/* SEV state cannot be controlled by a command line option */
sme_me_mask = me_mask;
- physical_mask &= ~sme_me_mask;
- return;
+ goto out;
}
/*
@@ -600,6 +600,9 @@ void __init sme_enable(struct boot_params *bp)
sme_me_mask = 0;
else
sme_me_mask = active_by_default ? me_mask : 0;
-
- physical_mask &= ~sme_me_mask;
+out:
+ if (sme_me_mask) {
+ physical_mask &= ~sme_me_mask;
+ cc_set_vendor(CC_VENDOR_AMD);
+ }
}
|