Re: [PATCH v2 35/45] KVM: s390: Manually invoke vcpu setup during kvm_arch_vcpu_create()

[Cornelia Huck]

On Fri, 20 Dec 2019 07:56:07 -0800
Sean Christopherson <sean.j.christopherson@xxxxxxxxx> wrote:

> On Fri, Dec 20, 2019 at 11:04:45AM +0100, Cornelia Huck wrote:
> > On Wed, 18 Dec 2019 13:55:20 -0800
> > Sean Christopherson <sean.j.christopherson@xxxxxxxxx> wrote:
> >   
> > > Rename kvm_arch_vcpu_setup() to kvm_s390_vcpu_setup() and manually call
> > > the new function during kvm_arch_vcpu_create().  Define an empty
> > > kvm_arch_vcpu_setup() as it's still required for compilation.  This
> > > is effectively a nop as kvm_arch_vcpu_create() and kvm_arch_vcpu_setup()
> > > are called back-to-back by common KVM code.  Obsoleting
> > > kvm_arch_vcpu_setup() paves the way for its removal.
> > > 
> > > Note, gmap_remove() is now called if setup fails, as s390 was previously
> > > freeing it via kvm_arch_vcpu_destroy(), which is called by common KVM
> > > code if kvm_arch_vcpu_setup() fails.  
> > 
> > Yes, this looks like the only thing that needs to be undone
> > (sca_add_vcpu() is done later in the process.)
> > 
> > Maybe mention that gmap_remove() is for ucontrol only? I was confused
> > for a moment :)  
> 
> Will do.
> 
> Would it also make sense to open code __kvm_ucontrol_vcpu_init() in a
> separate patch immediately preceding this change?  That'd make it a little
> more obvious why gmap_remove() is called, and it would eliminate the
> "uninit" verbiage in the label, e.g.:

I'm a bit undecided here; especially as I'm not sure if there are any
future plans with ucontrol. I'll leave that for Christian and Janosch
to decide.