Re: [PATCH 1/2] kvm/x86: Hyper-V synthetic interrupt controller

2015-10-09 Thread Paolo Bonzini
On 09/10/2015 17:53, Roman Kagan wrote: > > I really don't like this auto-EOI extension, but I guess that's the > > spec. :( If it wasn't for it, you could do everything very easily in > > userspace using Google's proposed MSR exit. > I guess you're right. We'd probably have to (ab)use MSI for

[PATCH 1/2] kvm/x86: Hyper-V synthetic interrupt controller

2015-10-09 Thread Denis V. Lunev
From: Andrey Smetanin Synic is a lapic extension, which is controlled via MSRs and maintains for each vCPU - 16 synthetic interrupt "lines" (SINT's); each can be configured to trigger a specific interrupt vector optionally with auto-EOI semantics - a message page

[PATCH 2/2] kvm/x86: Hyper-V kvm exit

2015-10-09 Thread Denis V. Lunev
From: Andrey Smetanin A new vcpu exit is introduced to notify the userspace of the changes in Hyper-V synic configuraion triggered by guest writing to the corresponding MSRs. Signed-off-by: Andrey Smetanin Reviewed-by: Roman Kagan

[PATCH 0/2] Hyper-V synthetic interrupt controller

2015-10-09 Thread Denis V. Lunev
This patchset implements the KVM part of the synthetic interrupt controller (synic) which is a building block of the Hyper-V paravirtualized device bus (vmbus). Synic is a lapic extension, which is controlled via MSRs and maintains for each vCPU - 16 synthetic interrupt "lines" (SINT's); each

Re: [PATCH 2/2] kvm/x86: Hyper-V kvm exit

2015-10-09 Thread Paolo Bonzini
On 09/10/2015 15:39, Denis V. Lunev wrote: > From: Andrey Smetanin > > A new vcpu exit is introduced to notify the userspace of the > changes in Hyper-V synic configuraion triggered by guest writing to the > corresponding MSRs. > > Signed-off-by: Andrey Smetanin

Re: [PATCH 1/2] kvm/x86: Hyper-V synthetic interrupt controller

2015-10-09 Thread Paolo Bonzini
Christian, the question for you is towards the end... On 09/10/2015 15:39, Denis V. Lunev wrote: > diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c > index 62cf8c9..15c3c02 100644 > --- a/arch/x86/kvm/hyperv.c > +++ b/arch/x86/kvm/hyperv.c > @@ -23,13 +23,265 @@ > > #include "x86.h"

Re: [PATCH 2/2] kvm/x86: Hyper-V kvm exit

2015-10-09 Thread Paolo Bonzini
On 09/10/2015 16:53, Roman Kagan wrote: >> > Why is this exit necessary? > The guest writes to synic-related MSRs and that should take "immediate" > effect. > > E.g. it may decide to disable or relocate the message page by writing to > SIMP MSR. The host is then supposed to stop accessing the