RE: [PATCH 0/2] KVM: xen: update shared_info when long_mode is set

[Durrant, Paul]

> -----Original Message-----
> From: Sean Christopherson <seanjc@xxxxxxxxxx>
> Sent: 01 December 2023 16:46
> To: Paul Durrant <paul@xxxxxxx>
> Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>; Paolo Bonzini <pbonzini@xxxxxxxxxx>; Thomas Gleixner
> <tglx@xxxxxxxxxxxxx>; Ingo Molnar <mingo@xxxxxxxxxx>; Borislav Petkov <bp@xxxxxxxxx>; Dave Hansen
> <dave.hansen@xxxxxxxxxxxxxxx>; x86@xxxxxxxxxx; H. Peter Anvin <hpa@xxxxxxxxx>; kvm@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx
> Subject: RE: [EXTERNAL] [PATCH 0/2] KVM: xen: update shared_info when long_mode is set
> 
> CAUTION: This email originated from outside of the organization. Do not click links or open
> attachments unless you can confirm the sender and know the content is safe.
> 
> 
> 
> On Fri, Dec 01, 2023, Paul Durrant wrote:
> > From: Paul Durrant <pdurrant@xxxxxxxxxx>
> >
> > This series is based on my v9 of my "update shared_info and vcpu_info
> > handling" series [1] and fixes an issue that was latent before the
> > "allow shared_info to be mapped by fixed HVA" patch of that series allowed
> > a VMM to set up shared_info before the VM booted and then leave it alone.
> 
> Uh, what?   If this is fixing an existing bug then it really shouldn't take a
> dependency on a rather large and non-trivial series.  If the bug can only manifest
> as a result of said series, then the fix absolutely belongs in that series.
> 

There's been radio silence on that series for a while so I was unsure of the status.

> This change from patch 1 in particular:
> 
>  -static int kvm_xen_shared_info_init(struct kvm *kvm, u64 addr, bool addr_is_gfn)
>  +static int kvm_xen_shared_info_init(struct kvm *kvm)
> 
> practically screams for inclusion in that series which does:
> 
>  -static int kvm_xen_shared_info_init(struct kvm *kvm, gfn_t gfn)
>  +static int kvm_xen_shared_info_init(struct kvm *kvm, u64 addr, bool addr_is_gfn)
> 
> Why not get the code right the first time instead of fixing it up in a completely
> different series?

Sure, I can fold it in.

  Paul