From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:40139 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752364AbcITMKu (ORCPT ); Tue, 20 Sep 2016 08:10:50 -0400 Subject: Patch "Revert "KVM: x86: fix missed hardware breakpoints"" has been added to the 4.4-stable tree To: pbonzini@redhat.com, gregkh@linuxfoundation.org, matt@codeblueprint.co.uk Cc: , From: Date: Tue, 20 Sep 2016 14:10:51 +0200 In-Reply-To: <1473976363-22653-1-git-send-email-pbonzini@redhat.com> Message-ID: <147437345119587@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled Revert "KVM: x86: fix missed hardware breakpoints" to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: revert-kvm-x86-fix-missed-hardware-breakpoints.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From pbonzini@redhat.com Tue Sep 20 14:08:11 2016 From: Paolo Bonzini Date: Thu, 15 Sep 2016 23:52:43 +0200 Subject: Revert "KVM: x86: fix missed hardware breakpoints" To: stable@vger.kernel.org Cc: matt@codeblueprint.co.uk, Paolo Bonzini Message-ID: <1473976363-22653-1-git-send-email-pbonzini@redhat.com> From: Paolo Bonzini [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 --- arch/x86/kvm/x86.c | 1 - 1 file changed, 1 deletion(-) --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2735,7 +2735,6 @@ void kvm_arch_vcpu_load(struct kvm_vcpu } 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) Patches currently in stable-queue which might be from pbonzini@redhat.com are queue-4.4/mips-kvm-check-for-pfn-noslot-case.patch queue-4.4/revert-kvm-x86-fix-missed-hardware-breakpoints.patch