diff mbox series

[Part2,v5,01/45] x86/cpufeatures: Add SEV-SNP CPU feature

Message ID 20210820155918.7518-2-brijesh.singh@amd.com (mailing list archive)
State New
Headers show
Series Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support | expand

Commit Message

Brijesh Singh Aug. 20, 2021, 3:58 p.m. UTC
Add CPU feature detection for Secure Encrypted Virtualization with
Secure Nested Paging. This feature adds a strong memory integrity
protection to help prevent malicious hypervisor-based attacks like
data replay, memory re-mapping, and more.

Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---
 arch/x86/include/asm/cpufeatures.h       | 1 +
 arch/x86/kernel/cpu/amd.c                | 3 ++-
 tools/arch/x86/include/asm/cpufeatures.h | 1 +
 3 files changed, 4 insertions(+), 1 deletion(-)

Comments

Borislav Petkov Sept. 16, 2021, 4:56 p.m. UTC | #1
On Fri, Aug 20, 2021 at 10:58:34AM -0500, Brijesh Singh wrote:
> Add CPU feature detection for Secure Encrypted Virtualization with
> Secure Nested Paging. This feature adds a strong memory integrity
> protection to help prevent malicious hypervisor-based attacks like
> data replay, memory re-mapping, and more.
> 
> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
> ---
>  arch/x86/include/asm/cpufeatures.h       | 1 +
>  arch/x86/kernel/cpu/amd.c                | 3 ++-
>  tools/arch/x86/include/asm/cpufeatures.h | 1 +
>  3 files changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
> index d0ce5cfd3ac1..62f458680772 100644
> --- a/arch/x86/include/asm/cpufeatures.h
> +++ b/arch/x86/include/asm/cpufeatures.h
> @@ -398,6 +398,7 @@
>  #define X86_FEATURE_SEV			(19*32+ 1) /* AMD Secure Encrypted Virtualization */
>  #define X86_FEATURE_VM_PAGE_FLUSH	(19*32+ 2) /* "" VM Page Flush MSR is supported */
>  #define X86_FEATURE_SEV_ES		(19*32+ 3) /* AMD Secure Encrypted Virtualization - Encrypted State */
> +#define X86_FEATURE_SEV_SNP		(19*32+4)  /* AMD Secure Encrypted Virtualization - Secure Nested Paging */

s/AMD Secure Encrypted Virtualization/AMD SEV/g

Bit 1 above already has that string - no need for repeating it
everywhere.

Also, note the vertical alignment (space after the '+'):

					(19*32+ 4)
Brijesh Singh Sept. 16, 2021, 5:35 p.m. UTC | #2
On 9/16/21 11:56 AM, Borislav Petkov wrote:
> On Fri, Aug 20, 2021 at 10:58:34AM -0500, Brijesh Singh wrote:
>> Add CPU feature detection for Secure Encrypted Virtualization with
>> Secure Nested Paging. This feature adds a strong memory integrity
>> protection to help prevent malicious hypervisor-based attacks like
>> data replay, memory re-mapping, and more.
>>
>> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
>> ---
>>   arch/x86/include/asm/cpufeatures.h       | 1 +
>>   arch/x86/kernel/cpu/amd.c                | 3 ++-
>>   tools/arch/x86/include/asm/cpufeatures.h | 1 +
>>   3 files changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
>> index d0ce5cfd3ac1..62f458680772 100644
>> --- a/arch/x86/include/asm/cpufeatures.h
>> +++ b/arch/x86/include/asm/cpufeatures.h
>> @@ -398,6 +398,7 @@
>>   #define X86_FEATURE_SEV			(19*32+ 1) /* AMD Secure Encrypted Virtualization */
>>   #define X86_FEATURE_VM_PAGE_FLUSH	(19*32+ 2) /* "" VM Page Flush MSR is supported */
>>   #define X86_FEATURE_SEV_ES		(19*32+ 3) /* AMD Secure Encrypted Virtualization - Encrypted State */
>> +#define X86_FEATURE_SEV_SNP		(19*32+4)  /* AMD Secure Encrypted Virtualization - Secure Nested Paging */
> 
> s/AMD Secure Encrypted Virtualization/AMD SEV/g
> 
> Bit 1 above already has that string - no need for repeating it
> everywhere.
> 
> Also, note the vertical alignment (space after the '+'):
> 
> 					(19*32+ 4)
> 

Noted. I will fix in next rev. thanks
diff mbox series

Patch

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index d0ce5cfd3ac1..62f458680772 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -398,6 +398,7 @@ 
 #define X86_FEATURE_SEV			(19*32+ 1) /* AMD Secure Encrypted Virtualization */
 #define X86_FEATURE_VM_PAGE_FLUSH	(19*32+ 2) /* "" VM Page Flush MSR is supported */
 #define X86_FEATURE_SEV_ES		(19*32+ 3) /* AMD Secure Encrypted Virtualization - Encrypted State */
+#define X86_FEATURE_SEV_SNP		(19*32+4)  /* AMD Secure Encrypted Virtualization - Secure Nested Paging */
 #define X86_FEATURE_SME_COHERENT	(19*32+10) /* "" AMD hardware-enforced cache coherency */
 
 /*
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index b7c003013d41..3e6a586fb589 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -586,7 +586,7 @@  static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
 	 *	      If BIOS has not enabled SME then don't advertise the
 	 *	      SME feature (set in scattered.c).
 	 *   For SEV: If BIOS has not enabled SEV then don't advertise the
-	 *            SEV and SEV_ES feature (set in scattered.c).
+	 *            SEV, SEV_ES and SEV_SNP feature.
 	 *
 	 *   In all cases, since support for SME and SEV requires long mode,
 	 *   don't advertise the feature under CONFIG_X86_32.
@@ -618,6 +618,7 @@  static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
 clear_sev:
 		setup_clear_cpu_cap(X86_FEATURE_SEV);
 		setup_clear_cpu_cap(X86_FEATURE_SEV_ES);
+		setup_clear_cpu_cap(X86_FEATURE_SEV_SNP);
 	}
 }
 
diff --git a/tools/arch/x86/include/asm/cpufeatures.h b/tools/arch/x86/include/asm/cpufeatures.h
index d0ce5cfd3ac1..62f458680772 100644
--- a/tools/arch/x86/include/asm/cpufeatures.h
+++ b/tools/arch/x86/include/asm/cpufeatures.h
@@ -398,6 +398,7 @@ 
 #define X86_FEATURE_SEV			(19*32+ 1) /* AMD Secure Encrypted Virtualization */
 #define X86_FEATURE_VM_PAGE_FLUSH	(19*32+ 2) /* "" VM Page Flush MSR is supported */
 #define X86_FEATURE_SEV_ES		(19*32+ 3) /* AMD Secure Encrypted Virtualization - Encrypted State */
+#define X86_FEATURE_SEV_SNP		(19*32+4)  /* AMD Secure Encrypted Virtualization - Secure Nested Paging */
 #define X86_FEATURE_SME_COHERENT	(19*32+10) /* "" AMD hardware-enforced cache coherency */
 
 /*