Re: [PATCH v2 1/5] x86/kvm: rename HV_X64_MSR_APIC_ASSIST_PAGE to HV_X64_MSR_VP_ASSIST_PAGE

From: Radim KrÄmÃÅ
Date: Wed Mar 07 2018 - 13:05:34 EST


2018-03-07 19:48+0300, Roman Kagan:
> On Wed, Mar 07, 2018 at 05:19:44PM +0100, Radim KrÄmÃÅ wrote:
> > 2018-02-26 18:11+0100, Vitaly Kuznetsov:
> > > diff --git a/arch/x86/include/uapi/asm/hyperv.h b/arch/x86/include/uapi/asm/hyperv.h
> > > @@ -275,10 +275,10 @@ struct hv_tsc_emulation_status {
> > > #define HVCALL_POST_MESSAGE 0x005c
> > > #define HVCALL_SIGNAL_EVENT 0x005d
> > >
> > > -#define HV_X64_MSR_APIC_ASSIST_PAGE_ENABLE 0x00000001
> > > -#define HV_X64_MSR_APIC_ASSIST_PAGE_ADDRESS_SHIFT 12
> > > -#define HV_X64_MSR_APIC_ASSIST_PAGE_ADDRESS_MASK \
> > > - (~((1ull << HV_X64_MSR_APIC_ASSIST_PAGE_ADDRESS_SHIFT) - 1))
> >
> > Removing definitions from userspace api isn't a good idea.
> >
> > I have no idea why hyper.h is a userspace api, though -- Linux doesn't
> > define any of those, so we could copy the definitions to a private
> > header, rename, and never look at this file again.
>
> That was a thinko when it was moved to uapi, and it has already been
> identified as a problem, so now QEMU has its own header with the
> definitions it needs, and I'm unaware of any other userspace project
> that depends on this stuff. So I've been planning to remove it from
> uapi but still haven't got around to posting the patch :(

Great, let's be bold here.