From: Paolo Bonzini Date: Thu, 15 Sep 2016 21:52:43 +0000 (+0200) Subject: Revert "KVM: x86: fix missed hardware breakpoints" X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=92c67861dab5e7ac2593609cb27d92751891e808;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git Revert "KVM: x86: fix missed hardware breakpoints" [the change is part of 70e4da7a8ff62f2775337b705f45c804bb450454, which is already in stable kernels 4.1.y to 4.4.y. this part of the fix however was later undone, so remove the line again] 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. This happened because [0] and [1] are the same patch. [0] and [1] come from two different merges, and the later merge is trivially resolved; when [2] is applied it reverts both of them. Instead, when using the [1][2][0] order, patches applies normally but "KVM: x86: fix missed hardware breakpoints" is present in the final tree. Reported-by: Matt Fleming Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index be222666b1c2..d7cb9577fa31 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2735,7 +2735,6 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) } kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); - vcpu->arch.switch_db_regs |= KVM_DEBUGREG_RELOAD; } void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)