Received-SPF: pass (google.com: domain of linux-kernel+bounces-103670-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161;
Precedence: bulk
MIME-Version: 1.0
References: <20240308223702.1350851-1-seanjc@google.com> <20240308223702.1350851-5-seanjc@google.com>
In-Reply-To: <20240308223702.1350851-5-seanjc@google.com>
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Thu, 14 Mar 2024 19:31:30 +0100
Message-ID: <CABgObfa3By9GU9_8FmqHQK-AxWU3ocbBkQK0xXwx2XRDP828dg@mail.gmail.com>
Subject: Re: [GIT PULL] KVM: x86: MMU changes for 6.9
To: Sean Christopherson <seanjc@google.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Fri, Mar 8, 2024 at 11:37=E2=80=AFPM Sean Christopherson <seanjc@google.=
com> wrote:
>
>  - Zap TDP MMU roots at 4KiB granularity to minimize the delay in yieldin=
g if
>    a reschedule is needed, e.g. if a high priority task needs to run.  Be=
cause
>    KVM doesn't support yielding in the middle of processing a zapped non-=
leaf
>    SPTE, zapping at 1GiB granularity can result in multi-millisecond lag =
when
>    attempting to schedule in a high priority.
>

Would 2 MiB provide a nice middle ground?

Paolo