diff mbox series

[V3,02/13] x86/HV: Initialize shared memory boundary in the Isolation VM.

Message ID 20210809175620.720923-3-ltykernel@gmail.com
State Superseded
Headers show
Series x86/Hyper-V: Add Hyper-V Isolation VM support | expand

Commit Message

Tianyu Lan Aug. 9, 2021, 5:56 p.m. UTC
From: Tianyu Lan <Tianyu.Lan@microsoft.com>

Hyper-V exposes shared memory boundary via cpuid
HYPERV_CPUID_ISOLATION_CONFIG and store it in the
shared_gpa_boundary of ms_hyperv struct. This prepares
to share memory with host for SNP guest.

Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
---
 arch/x86/kernel/cpu/mshyperv.c |  2 ++
 include/asm-generic/mshyperv.h | 12 +++++++++++-
 2 files changed, 13 insertions(+), 1 deletion(-)

Comments

Tianyu Lan Aug. 14, 2021, 1:32 p.m. UTC | #1
On 8/13/2021 3:18 AM, Michael Kelley wrote:
> From: Tianyu Lan <ltykernel@gmail.com> Sent: Monday, August 9, 2021 10:56 AM
>> Subject: [PATCH V3 02/13] x86/HV: Initialize shared memory boundary in the Isolation VM.
> 
> As with Patch 1, use the "x86/hyperv:" tag in the Subject line.
> 
>>
>> From: Tianyu Lan <Tianyu.Lan@microsoft.com>
>>
>> Hyper-V exposes shared memory boundary via cpuid
>> HYPERV_CPUID_ISOLATION_CONFIG and store it in the
>> shared_gpa_boundary of ms_hyperv struct. This prepares
>> to share memory with host for SNP guest.
>>
>> Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
>> ---
>>   arch/x86/kernel/cpu/mshyperv.c |  2 ++
>>   include/asm-generic/mshyperv.h | 12 +++++++++++-
>>   2 files changed, 13 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
>> index 6b5835a087a3..2b7f396ef1a5 100644
>> --- a/arch/x86/kernel/cpu/mshyperv.c
>> +++ b/arch/x86/kernel/cpu/mshyperv.c
>> @@ -313,6 +313,8 @@ static void __init ms_hyperv_init_platform(void)
>>   	if (ms_hyperv.priv_high & HV_ISOLATION) {
>>   		ms_hyperv.isolation_config_a = cpuid_eax(HYPERV_CPUID_ISOLATION_CONFIG);
>>   		ms_hyperv.isolation_config_b = cpuid_ebx(HYPERV_CPUID_ISOLATION_CONFIG);
>> +		ms_hyperv.shared_gpa_boundary =
>> +			(u64)1 << ms_hyperv.shared_gpa_boundary_bits;
> 
> You could use BIT_ULL() here, but it's kind of a shrug.


Good suggestion. Thanks.

> 
>>
>>   		pr_info("Hyper-V: Isolation Config: Group A 0x%x, Group B 0x%x\n",
>>   			ms_hyperv.isolation_config_a, ms_hyperv.isolation_config_b);
>> diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
>> index 4269f3174e58..aa26d24a5ca9 100644
>> --- a/include/asm-generic/mshyperv.h
>> +++ b/include/asm-generic/mshyperv.h
>> @@ -35,8 +35,18 @@ struct ms_hyperv_info {
>>   	u32 max_vp_index;
>>   	u32 max_lp_index;
>>   	u32 isolation_config_a;
>> -	u32 isolation_config_b;
>> +	union {
>> +		u32 isolation_config_b;
>> +		struct {
>> +			u32 cvm_type : 4;
>> +			u32 Reserved11 : 1;
>> +			u32 shared_gpa_boundary_active : 1;
>> +			u32 shared_gpa_boundary_bits : 6;
>> +			u32 Reserved12 : 20;
> 
> Any reason to name the reserved fields as "11" and "12"?  It
> just looks a bit unusual.  And I'd suggest lowercase "r".
> 

Yes, will update in the next version.

>> +		};
>> +	};
>>   	void  __percpu **ghcb_base;
>> +	u64 shared_gpa_boundary;
>>   };
>>   extern struct ms_hyperv_info ms_hyperv;
>>
>> --
>> 2.25.1
>
diff mbox series

Patch

diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 6b5835a087a3..2b7f396ef1a5 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -313,6 +313,8 @@  static void __init ms_hyperv_init_platform(void)
 	if (ms_hyperv.priv_high & HV_ISOLATION) {
 		ms_hyperv.isolation_config_a = cpuid_eax(HYPERV_CPUID_ISOLATION_CONFIG);
 		ms_hyperv.isolation_config_b = cpuid_ebx(HYPERV_CPUID_ISOLATION_CONFIG);
+		ms_hyperv.shared_gpa_boundary =
+			(u64)1 << ms_hyperv.shared_gpa_boundary_bits;
 
 		pr_info("Hyper-V: Isolation Config: Group A 0x%x, Group B 0x%x\n",
 			ms_hyperv.isolation_config_a, ms_hyperv.isolation_config_b);
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index 4269f3174e58..aa26d24a5ca9 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -35,8 +35,18 @@  struct ms_hyperv_info {
 	u32 max_vp_index;
 	u32 max_lp_index;
 	u32 isolation_config_a;
-	u32 isolation_config_b;
+	union {
+		u32 isolation_config_b;
+		struct {
+			u32 cvm_type : 4;
+			u32 Reserved11 : 1;
+			u32 shared_gpa_boundary_active : 1;
+			u32 shared_gpa_boundary_bits : 6;
+			u32 Reserved12 : 20;
+		};
+	};
 	void  __percpu **ghcb_base;
+	u64 shared_gpa_boundary;
 };
 extern struct ms_hyperv_info ms_hyperv;