Re: KVM patches applied in weird order in -stable

From: Greg KH
Date: Tue Sep 13 2016 - 21:20:10 EST


On Tue, Sep 13, 2016 at 06:58:40PM +0200, Paolo Bonzini wrote:
>
>
> On 13/09/2016 18:57, Greg KH wrote:
> >>>> > >> [0] commit 4e422bdd2f84 ("KVM: x86: fix missed hardware breakpoints")
> >>>> > >> [1] commit 172b2386ed16 ("KVM: x86: fix missed hardware breakpoints")
> >>>> > >> [2] commit 70e4da7a8ff6 ("KVM: x86: fix root cause for missed hardware breakpoints")
> >>>> > >>
> >>>> > >> but this is the order for linux-4.4.y
> >>>> > >>
> >>>> > >> [1] commit fc90441e728a ("KVM: x86: fix missed hardware breakpoints")
> >>>> > >> [2] commit 25e8618619a5 ("KVM: x86: fix root cause for missed hardware breakpoints")
> >>>> > >> [0] commit 0f6e5e26e68f ("KVM: x86: fix missed hardware breakpoints")
> >>>> > >>
> >>>> > >> The upshot is that KVM_DEBUGREG_RELOAD is always set when returning
> >>>> > >> from kvm_arch_vcpu_load() in stable, but not in Linus' tree.
> >>> > >
> >>> > > How would applying these in a different order cause breakage?
> >> >
> >> > [2] is reverting [0]+[1]. Stable is not due to the different order.
> > Really? Are you sure that [0] and [1] isn't just the same commit? It
> > looks like that to me.
>
> It is; "git" automatically resolved the conflicts when merging [1], and
> then [2] reverted the change. In stable, changing the order created a
> different conflict resolution.

Yes, given that I turn them into individual patches, the order I used
was really the only one that would work, and is how this happened :)

thanks,

greg k-h