KVM patches applied in weird order in -stable

From	Matt Fleming <matt@codeblueprint.co.uk>
Newsgroups	linux.kernel
Subject	KVM patches applied in weird order in -stable
Date	2016-09-13 17:00 +0200
Message-ID	<sgXlM-3gI-3@gated-at.bofh.it> (permalink)
Organization	linux.* mail to news gateway

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Folks,

While hunting down a performance issue involving KVM I was surprised
to see "native_set_debugreg()" as the first entry in `perf top`.

Digging deeper, it looks as though the following patches were applied
in the wrong order in -stable. This is the order as they appear in
Linus' tree,

 [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.

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KVM patches applied in weird order in -stable Matt Fleming <matt@codeblueprint.co.uk> - 2016-09-13 17:00 +0200
  Re: KVM patches applied in weird order in -stable Greg KH <gregkh@linuxfoundation.org> - 2016-09-13 17:00 +0200
    Re: KVM patches applied in weird order in -stable Paolo Bonzini <pbonzini@redhat.com> - 2016-09-13 18:30 +0200
      Re: KVM patches applied in weird order in -stable Greg KH <gregkh@linuxfoundation.org> - 2016-09-13 19:00 +0200
        Re: KVM patches applied in weird order in -stable Paolo Bonzini <pbonzini@redhat.com> - 2016-09-13 19:00 +0200
          Re: KVM patches applied in weird order in -stable Greg KH <gregkh@linuxfoundation.org> - 2016-09-14 03:30 +0200

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