From: Paul Durrant <[email protected]> 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 <[email protected]> Reviewed-by: David Woodhouse <[email protected]> --- Cc: Sean Christopherson <[email protected]> Cc: Paolo Bonzini <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: David Woodhouse <[email protected]> Cc: [email protected] v8: - New in this version. --- arch/x86/kvm/xen.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c index e53fad915a62..426306022c2f 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) -- 2.39.2
