Re: [PATCH v4 0/4] Add support for XMM fast hypercalls

From: Paolo Bonzini <pbonzini@redhat.com>
To: Siddharth Chandrasekaran <sidcha@amazon.de>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>,
	Haiyang Zhang <haiyangz@microsoft.com>,
	Stephen Hemminger <sthemmin@microsoft.com>,
	Wei Liu <wei.liu@kernel.org>, Dexuan Cui <decui@microsoft.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
	Sean Christopherson <seanjc@google.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Wanpeng Li <wanpengli@tencent.com>,
	Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>,
	Siddharth Chandrasekaran <sidcha.dev@gmail.com>,
	Alexander Graf <graf@amazon.com>,
	Evgeny Iakovlev <eyakovl@amazon.de>,
	Liran Alon <liran@amazon.com>,
	Ioannis Aslanidis <iaslan@amazon.de>,
	linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org,
	kvm@vger.kernel.org
Subject: Re: [PATCH v4 0/4] Add support for XMM fast hypercalls
Date: Tue, 6 Jul 2021 18:36:05 +0200	[thread overview]
Message-ID: <d0d8c67f-ac0b-255e-c7a3-e7d4ac37a654@redhat.com> (raw)
In-Reply-To: <20210706151535.GA28697@u366d62d47e3651.ant.amazon.com>

On 06/07/21 17:15, Siddharth Chandrasekaran wrote:
> On Tue, Jul 06, 2021 at 05:04:59PM +0200, Paolo Bonzini wrote:
>> On 30/06/21 13:56, Siddharth Chandrasekaran wrote:
>>> On Wed, May 26, 2021 at 10:56:07AM +0200, Siddharth Chandrasekaran wrote:
>>>> Hyper-V supports the use of XMM registers to perform fast hypercalls.
>>>> This allows guests to take advantage of the improved performance of the
>>>> fast hypercall interface even though a hypercall may require more than
>>>> (the current maximum of) two general purpose registers.
>>>>
>>>> The XMM fast hypercall interface uses an additional six XMM registers
>>>> (XMM0 to XMM5) to allow the caller to pass an input parameter block of
>>>> up to 112 bytes. Hyper-V can also return data back to the guest in the
>>>> remaining XMM registers that are not used by the current hypercall.
>>>>
>>>> Although the Hyper-v TLFS mentions that a guest cannot use this feature
>>>> unless the hypervisor advertises support for it, some hypercalls which
>>>> we plan on upstreaming in future uses them anyway. This patchset adds
>>>> necessary infrastructure for handling input/output via XMM registers and
>>>> patches kvm_hv_flush_tlb() to use xmm input arguments.
>>>
>>> Hi Paolo,
>>>
>>> Are you expecting more reviews on these patches?
>>
>> They are part of 5.14 already. :)
> 
> Ahh, I see them now. I was expecting them to show up in master - that was
> the confusion.

No problem! The patches for the rc period (in your case it was 5.13) go 
in master, while yours ended up in next (destined for 5.14).

I usually update master only after 5.14-rc1 is out.  In this case I 
didn't even have access to kvm.git on the day that Linus pulled your 
patches into his tree.

Paolo