[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [PATCH for-4.13 v3 2/2] x86/vmx: always sync PIR to IRR before vmentry
On Tue, Nov 26, 2019 at 05:50:32PM +0100, Jan Beulich wrote: > On 26.11.2019 14:26, Roger Pau Monne wrote: > > --- a/xen/arch/x86/hvm/irq.c > > +++ b/xen/arch/x86/hvm/irq.c > > @@ -515,7 +515,11 @@ void hvm_set_callback_via(struct domain *d, uint64_t > > via) > > struct hvm_intack hvm_vcpu_has_pending_irq(struct vcpu *v) > > { > > struct hvm_domain *plat = &v->domain->arch.hvm; > > - int vector; > > + /* > > + * Always call vlapic_has_pending_irq so that PIR is synced into IRR > > when > > + * using posted interrupts. > > + */ > > + int vector = vlapic_has_pending_irq(v); > > Did you consider doing this conditionally either here ... > > > @@ -530,7 +534,6 @@ struct hvm_intack hvm_vcpu_has_pending_irq(struct vcpu > > *v) > > if ( vlapic_accept_pic_intr(v) && plat->vpic[0].int_output ) > > return hvm_intack_pic(0); > > > > - vector = vlapic_has_pending_irq(v); > > if ( vector != -1 ) > > return hvm_intack_lapic(vector); > > ... or here? I'm afraid I don't follow. The whole point of this change is to ensure vlapic_has_pending_irq is unconditionally called in hvm_vcpu_has_pending_irq, so I'm not sure what you mean by "doing this conditionally...". > I ask not only because the function isn't exactly > cheap to call (as iirc you did also mention during the v2 > discussion), but also because of its interaction with Viridian > and nested mode. In case of problems there, avoiding the use > of interrupt posting would be a workaround in such cases then. Would you like me to export something like vlapic_sync_pir_to_irr and call it unconditionally instead of calling vlapic_has_pending_irq? Thanks, Roger. _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxxx https://lists.xenproject.org/mailman/listinfo/xen-devel
|
![]() |
Lists.xenproject.org is hosted with RackSpace, monitoring our |