diff mbox series

[v5,02/10] x86/mshyperv: Add support for extended Hyper-V features

Message ID 1740611284-27506-3-git-send-email-nunodasneves@linux.microsoft.com (mailing list archive)
State New
Headers show
Series Introduce /dev/mshv root partition driver | expand

Commit Message

Nuno Das Neves Feb. 26, 2025, 11:07 p.m. UTC
From: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>

Extend the "ms_hyperv_info" structure to include a new field,
"ext_features", for capturing extended Hyper-V features.
Update the "ms_hyperv_init_platform" function to retrieve these features
using the cpuid instruction and include them in the informational output.

Signed-off-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
---
 arch/x86/kernel/cpu/mshyperv.c | 6 ++++--
 include/asm-generic/mshyperv.h | 1 +
 2 files changed, 5 insertions(+), 2 deletions(-)

Comments

Stanislav Kinsburskii Feb. 26, 2025, 11:27 p.m. UTC | #1
On Wed, Feb 26, 2025 at 03:07:56PM -0800, Nuno Das Neves wrote:
> From: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
> 
> Extend the "ms_hyperv_info" structure to include a new field,
> "ext_features", for capturing extended Hyper-V features.
> Update the "ms_hyperv_init_platform" function to retrieve these features
> using the cpuid instruction and include them in the informational output.
> 

Reviewed-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Roman Kisel Feb. 27, 2025, 5:59 p.m. UTC | #2
On 2/26/2025 3:07 PM, Nuno Das Neves wrote:
> From: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
[...]
>   
> -	pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, hints 0x%x, misc 0x%x\n",
> -		ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints,
> +	pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, ext 0x%x, hints 0x%x, misc 0x%x\n",
> +		ms_hyperv.features, ms_hyperv.priv_high,
> +		ms_hyperv.ext_features, ms_hyperv.hints,
>   		ms_hyperv.misc_features);

Would using %#x instead of 0x%x be better in your opinion?

[..]
Easwar Hariharan Feb. 27, 2025, 6:17 p.m. UTC | #3
On 2/26/2025 3:07 PM, Nuno Das Neves wrote:
> From: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
> 
> Extend the "ms_hyperv_info" structure to include a new field,
> "ext_features", for capturing extended Hyper-V features.
> Update the "ms_hyperv_init_platform" function to retrieve these features
> using the cpuid instruction and include them in the informational output.
> 
> Signed-off-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
> Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
> ---
>  arch/x86/kernel/cpu/mshyperv.c | 6 ++++--
>  include/asm-generic/mshyperv.h | 1 +
>  2 files changed, 5 insertions(+), 2 deletions(-)

Looks good to me.

Reviewed-by: Easwar Hariharan <eahariha@linux.microsoft.com>
Nuno Das Neves Feb. 28, 2025, 12:17 a.m. UTC | #4
On 2/27/2025 9:59 AM, Roman Kisel wrote:
> 
> 
> On 2/26/2025 3:07 PM, Nuno Das Neves wrote:
>> From: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
> [...]
>>   -    pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, hints 0x%x, misc 0x%x\n",
>> -        ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints,
>> +    pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, ext 0x%x, hints 0x%x, misc 0x%x\n",
>> +        ms_hyperv.features, ms_hyperv.priv_high,
>> +        ms_hyperv.ext_features, ms_hyperv.hints,
>>           ms_hyperv.misc_features);
> 
> Would using %#x instead of 0x%x be better in your opinion?
> 
It's a reasonable suggestion. I'm not sure if it's worth another
version, if this patch seems good enough to merge as-is.
However if I'm doing another version of this series that still
includes this patch, then I can certainly make the change.

Thanks!

> [..]
diff mbox series

Patch

diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 4f01f424ea5b..2c29dfd6de19 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -434,13 +434,15 @@  static void __init ms_hyperv_init_platform(void)
 	 */
 	ms_hyperv.features = cpuid_eax(HYPERV_CPUID_FEATURES);
 	ms_hyperv.priv_high = cpuid_ebx(HYPERV_CPUID_FEATURES);
+	ms_hyperv.ext_features = cpuid_ecx(HYPERV_CPUID_FEATURES);
 	ms_hyperv.misc_features = cpuid_edx(HYPERV_CPUID_FEATURES);
 	ms_hyperv.hints    = cpuid_eax(HYPERV_CPUID_ENLIGHTMENT_INFO);
 
 	hv_max_functions_eax = cpuid_eax(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS);
 
-	pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, hints 0x%x, misc 0x%x\n",
-		ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints,
+	pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, ext 0x%x, hints 0x%x, misc 0x%x\n",
+		ms_hyperv.features, ms_hyperv.priv_high,
+		ms_hyperv.ext_features, ms_hyperv.hints,
 		ms_hyperv.misc_features);
 
 	ms_hyperv.max_vp_index = cpuid_eax(HYPERV_CPUID_IMPLEMENT_LIMITS);
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index dc4729dba9ef..c020d5d0ec2a 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -36,6 +36,7 @@  enum hv_partition_type {
 struct ms_hyperv_info {
 	u32 features;
 	u32 priv_high;
+	u32 ext_features;
 	u32 misc_features;
 	u32 hints;
 	u32 nested_features;