This is a note to let you know that I've just added the patch titled
KVM MMU: check pending exception before injecting APF
to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: kvm-mmu-check-pending-exception-before-injecting-apf.patch and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From 2a266f23550be997d783f27e704b9b40c4010292 Mon Sep 17 00:00:00 2001
From: Haozhong Zhang haozhong.zhang@intel.com Date: Wed, 10 Jan 2018 21:44:42 +0800 Subject: KVM MMU: check pending exception before injecting APF
From: Haozhong Zhang haozhong.zhang@intel.com
commit 2a266f23550be997d783f27e704b9b40c4010292 upstream.
For example, when two APF's for page ready happen after one exit and the first one becomes pending, the second one will result in #DF. Instead, just handle the second page fault synchronously.
Reported-by: Ross Zwisler zwisler@gmail.com Message-ID: CAOxpaSUBf8QoOZQ1p4KfUp0jq76OKfGY4Uxs-Gg8ngReD99xww@mail.gmail.com Reported-by: Alec Blayne ab@tevsa.net Signed-off-by: Haozhong Zhang haozhong.zhang@intel.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kvm/mmu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3784,7 +3784,8 @@ static int kvm_arch_setup_async_pf(struc bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu) { if (unlikely(!lapic_in_kernel(vcpu) || - kvm_event_needs_reinjection(vcpu))) + kvm_event_needs_reinjection(vcpu) || + vcpu->arch.exception.pending)) return false;
if (!vcpu->arch.apf.delivery_as_pf_vmexit && is_guest_mode(vcpu))
Patches currently in stable-queue which might be from haozhong.zhang@intel.com are
queue-4.14/kvm-mmu-check-pending-exception-before-injecting-apf.patch