Re: [RFC v2-fix 1/1] x86/tdx: Wire up KVM hypercalls

[Dave Hansen]

On 5/18/21 1:12 PM, Kuppuswamy, Sathyanarayanan wrote:
>>> [Isaku: proposed KVM VENDOR string]
>>> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
>>> Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
>>> Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
>>> Signed-off-by: Kuppuswamy Sathyanarayanan
>>> <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
>>
>> This SoB chain is odd.  Kirill wrote this, sent it to Isaku, who sent it
>> to Sathya?
> 
> Initially we have used "0" as vendor ID for KVM. But Isaku proposed a new
> value for it and sent a patch to fix it. But, I did not want to carry it as
> separate patch (for one line change). So I have merged his change with
> this patch, and added his signed-off with comment ([Isaku: proposed KVM
> VENDOR string])
> 
> +#define TDVMCALL_VENDOR_KVM            0x4d564b2e584454 /* "TDX.KVM" */

That's a combined Co-developed-by+Signed-off-by situation.  You don't
add a bare SoB for that.

But, seriously, you don't need to preserve a SoB for a one-line patch.
Just pull the line in and make a note in the changelog.