mshv: add a missing padding field

[PATCH] mshv: add a missing padding field

Posted by wei.liu@kernel.org 1 month, 3 weeks ago

From: Wei Liu <wei.liu@kernel.org>

That was missed when importing the header.

Reported-by: Doru Blânzeanu <dblanzeanu@linux.microsoft.com>
Reported-by: Magnus Kulke <magnuskulke@linux.microsoft.com>
Fixes: e68bda71a2384 ("hyperv: Add new Hyper-V headers in include/hyperv")
Cc: stable@kernel.org
Signed-off-by: Wei Liu <wei.liu@kernel.org>
---
 include/hyperv/hvhdk.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/hyperv/hvhdk.h b/include/hyperv/hvhdk.h
index 5e83d3714966..ff7ca9ee1bd4 100644
--- a/include/hyperv/hvhdk.h
+++ b/include/hyperv/hvhdk.h
@@ -79,6 +79,7 @@ struct hv_vp_register_page {
 
 		u64 registers[18];
 	};
+	__u8 reserved[8];
 	/* Volatile XMM registers (HV_X64_REGISTER_CLASS_XMM) */
 	union {
 		struct {
-- 
2.43.0

Re: [PATCH] mshv: add a missing padding field

Posted by Easwar Hariharan 1 month, 3 weeks ago

On 4/23/2026 10:26 AM, wei.liu@kernel.org wrote:
> From: Wei Liu <wei.liu@kernel.org>
> 
> That was missed when importing the header.
> 
> Reported-by: Doru Blânzeanu <dblanzeanu@linux.microsoft.com>
> Reported-by: Magnus Kulke <magnuskulke@linux.microsoft.com>
> Fixes: e68bda71a2384 ("hyperv: Add new Hyper-V headers in include/hyperv")
> Cc: stable@kernel.org
> Signed-off-by: Wei Liu <wei.liu@kernel.org>
> ---
>  include/hyperv/hvhdk.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/include/hyperv/hvhdk.h b/include/hyperv/hvhdk.h
> index 5e83d3714966..ff7ca9ee1bd4 100644
> --- a/include/hyperv/hvhdk.h
> +++ b/include/hyperv/hvhdk.h
> @@ -79,6 +79,7 @@ struct hv_vp_register_page {
>  
>  		u64 registers[18];
>  	};
> +	__u8 reserved[8];
>  	/* Volatile XMM registers (HV_X64_REGISTER_CLASS_XMM) */
>  	union {
>  		struct {


This is not a uapi, so why not just use u8 instead of __u8?
Or since it's 8 u8s, a u64?

Thanks,
Easwar (he/him)

Re: [PATCH] mshv: add a missing padding field

Posted by Easwar Hariharan 1 month, 3 weeks ago

On 4/23/2026 10:29 AM, Easwar Hariharan wrote:
> On 4/23/2026 10:26 AM, wei.liu@kernel.org wrote:
>> From: Wei Liu <wei.liu@kernel.org>
>>
>> That was missed when importing the header.
>>
>> Reported-by: Doru Blânzeanu <dblanzeanu@linux.microsoft.com>
>> Reported-by: Magnus Kulke <magnuskulke@linux.microsoft.com>
>> Fixes: e68bda71a2384 ("hyperv: Add new Hyper-V headers in include/hyperv")
>> Cc: stable@kernel.org
>> Signed-off-by: Wei Liu <wei.liu@kernel.org>
>> ---
>>  include/hyperv/hvhdk.h | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/include/hyperv/hvhdk.h b/include/hyperv/hvhdk.h
>> index 5e83d3714966..ff7ca9ee1bd4 100644
>> --- a/include/hyperv/hvhdk.h
>> +++ b/include/hyperv/hvhdk.h
>> @@ -79,6 +79,7 @@ struct hv_vp_register_page {
>>  
>>  		u64 registers[18];
>>  	};
>> +	__u8 reserved[8];
>>  	/* Volatile XMM registers (HV_X64_REGISTER_CLASS_XMM) */
>>  	union {
>>  		struct {
> 
> 
> This is not a uapi, so why not just use u8 instead of __u8?
> Or since it's 8 u8s, a u64?
> 
> Thanks,
> Easwar (he/him)

Hm, occurs to me that this would be used by VMMs, but then the registers
field just above used a u64 instead of a __u64....

Re: [PATCH] mshv: add a missing padding field

Posted by Wei Liu 1 month, 3 weeks ago

On Thu, Apr 23, 2026 at 10:32:58AM -0700, Easwar Hariharan wrote:
> On 4/23/2026 10:29 AM, Easwar Hariharan wrote:
> > On 4/23/2026 10:26 AM, wei.liu@kernel.org wrote:
> >> From: Wei Liu <wei.liu@kernel.org>
> >>
> >> That was missed when importing the header.
> >>
> >> Reported-by: Doru Blânzeanu <dblanzeanu@linux.microsoft.com>
> >> Reported-by: Magnus Kulke <magnuskulke@linux.microsoft.com>
> >> Fixes: e68bda71a2384 ("hyperv: Add new Hyper-V headers in include/hyperv")
> >> Cc: stable@kernel.org
> >> Signed-off-by: Wei Liu <wei.liu@kernel.org>
> >> ---
> >>  include/hyperv/hvhdk.h | 1 +
> >>  1 file changed, 1 insertion(+)
> >>
> >> diff --git a/include/hyperv/hvhdk.h b/include/hyperv/hvhdk.h
> >> index 5e83d3714966..ff7ca9ee1bd4 100644
> >> --- a/include/hyperv/hvhdk.h
> >> +++ b/include/hyperv/hvhdk.h
> >> @@ -79,6 +79,7 @@ struct hv_vp_register_page {
> >>  
> >>  		u64 registers[18];
> >>  	};
> >> +	__u8 reserved[8];
> >>  	/* Volatile XMM registers (HV_X64_REGISTER_CLASS_XMM) */
> >>  	union {
> >>  		struct {
> > 
> > 
> > This is not a uapi, so why not just use u8 instead of __u8?
> > Or since it's 8 u8s, a u64?
> > 
> > Thanks,
> > Easwar (he/him)
> 
> Hm, occurs to me that this would be used by VMMs, but then the registers
> field just above used a u64 instead of a __u64....

I fat-fingered u8 to __u8.  User space code has scripts to massage the
types as needed.

To remain consistent with the existing code, it should be u8.

I can change the type when I commit this.

Wei

> 
>

Re: [PATCH] mshv: add a missing padding field

Posted by Easwar Hariharan 1 month, 3 weeks ago

On 4/23/2026 11:14 AM, Wei Liu wrote:
> On Thu, Apr 23, 2026 at 10:32:58AM -0700, Easwar Hariharan wrote:
>> On 4/23/2026 10:29 AM, Easwar Hariharan wrote:
>>> On 4/23/2026 10:26 AM, wei.liu@kernel.org wrote:
>>>> From: Wei Liu <wei.liu@kernel.org>
>>>>
>>>> That was missed when importing the header.
>>>>
>>>> Reported-by: Doru Blânzeanu <dblanzeanu@linux.microsoft.com>
>>>> Reported-by: Magnus Kulke <magnuskulke@linux.microsoft.com>
>>>> Fixes: e68bda71a2384 ("hyperv: Add new Hyper-V headers in include/hyperv")
>>>> Cc: stable@kernel.org
>>>> Signed-off-by: Wei Liu <wei.liu@kernel.org>
>>>> ---
>>>>  include/hyperv/hvhdk.h | 1 +
>>>>  1 file changed, 1 insertion(+)
>>>>
>>>> diff --git a/include/hyperv/hvhdk.h b/include/hyperv/hvhdk.h
>>>> index 5e83d3714966..ff7ca9ee1bd4 100644
>>>> --- a/include/hyperv/hvhdk.h
>>>> +++ b/include/hyperv/hvhdk.h
>>>> @@ -79,6 +79,7 @@ struct hv_vp_register_page {
>>>>  
>>>>  		u64 registers[18];
>>>>  	};
>>>> +	__u8 reserved[8];
>>>>  	/* Volatile XMM registers (HV_X64_REGISTER_CLASS_XMM) */
>>>>  	union {
>>>>  		struct {
>>>
>>>
>>> This is not a uapi, so why not just use u8 instead of __u8?
>>> Or since it's 8 u8s, a u64?
>>>
>>> Thanks,
>>> Easwar (he/him)
>>
>> Hm, occurs to me that this would be used by VMMs, but then the registers
>> field just above used a u64 instead of a __u64....
> 
> I fat-fingered u8 to __u8.  User space code has scripts to massage the
> types as needed.
> 
> To remain consistent with the existing code, it should be u8.
> 
> I can change the type when I commit this.
> 
> Wei
Thanks, with that fixed:

Reviewed-by: Easwar Hariharan <easwar.hariharan@linux.microsoft.com>