From: Paul Durrant Date: Thu, 15 Feb 2024 15:28:58 +0000 (+0000) Subject: KVM: x86/xen: mark guest pages dirty with the pfncache lock held X-Git-Tag: microblaze-v6.10~93^2~2^2~20 X-Git-Url: http://git.monstr.eu/?a=commitdiff_plain;h=4438355ec6e165f73357203e0792079dec9e3059;p=linux-2.6-microblaze.git KVM: x86/xen: mark guest pages dirty with the pfncache lock held Sampling gpa and memslot from an unlocked pfncache may yield inconsistent values so, since there is no problem with calling mark_page_dirty_in_slot() with the pfncache lock held, relocate the calls in kvm_xen_update_runstate_guest() and kvm_xen_inject_pending_events() accordingly. Signed-off-by: Paul Durrant Reviewed-by: David Woodhouse Link: https://lore.kernel.org/r/20240215152916.1158-4-paul@xen.org Signed-off-by: Sean Christopherson --- diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c index 4b4e738c6f1b..f3327508ae41 100644 --- a/arch/x86/kvm/xen.c +++ b/arch/x86/kvm/xen.c @@ -452,14 +452,13 @@ static void kvm_xen_update_runstate_guest(struct kvm_vcpu *v, bool atomic) smp_wmb(); } - if (user_len2) + if (user_len2) { + mark_page_dirty_in_slot(v->kvm, gpc2->memslot, gpc2->gpa >> PAGE_SHIFT); read_unlock(&gpc2->lock); - - read_unlock_irqrestore(&gpc1->lock, flags); + } mark_page_dirty_in_slot(v->kvm, gpc1->memslot, gpc1->gpa >> PAGE_SHIFT); - if (user_len2) - mark_page_dirty_in_slot(v->kvm, gpc2->memslot, gpc2->gpa >> PAGE_SHIFT); + read_unlock_irqrestore(&gpc1->lock, flags); } void kvm_xen_update_runstate(struct kvm_vcpu *v, int state) @@ -565,13 +564,13 @@ void kvm_xen_inject_pending_events(struct kvm_vcpu *v) : "0" (evtchn_pending_sel32)); WRITE_ONCE(vi->evtchn_upcall_pending, 1); } + + mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT); read_unlock_irqrestore(&gpc->lock, flags); /* For the per-vCPU lapic vector, deliver it as MSI. */ if (v->arch.xen.upcall_vector) kvm_xen_inject_vcpu_vector(v); - - mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT); } int __kvm_xen_has_interrupt(struct kvm_vcpu *v)