On 04/08/16 10:10, Razvan Cojocaru wrote: > It is meaningless (and potentially dangerous - see > hvmemul_virtual_to_linear()) > to set mem_access_emulate_each_rep before xc_monitor_enable() (which allocates > vcpu->arch.vm_event) has been called, so return an error from the > XEN_DOMCTL_MONITOR_OP_EMULATE_EACH_REP hypercall when that is the case. > > Signed-off-by: Razvan Cojocaru <rcojoc...@bitdefender.com> > --- > xen/include/asm-x86/monitor.h | 15 +++++++++++++-- > 1 file changed, 13 insertions(+), 2 deletions(-) > > diff --git a/xen/include/asm-x86/monitor.h b/xen/include/asm-x86/monitor.h > index 0954b59..0544836 100644 > --- a/xen/include/asm-x86/monitor.h > +++ b/xen/include/asm-x86/monitor.h > @@ -35,11 +35,22 @@ int arch_monitor_domctl_op(struct domain *d, struct > xen_domctl_monitor_op *mop) > switch ( mop->op ) > { > case XEN_DOMCTL_MONITOR_OP_EMULATE_EACH_REP: > + { > + bool_t value = !!mop->event; > domain_pause(d); > - d->arch.mem_access_emulate_each_rep = !!mop->event; > + /* > + * Enabling emulate_each_rep without a vm_event subscriber > + * is meaningless. > + */ > + if ( !d->vcpu || !d->vcpu[0]->arch.vm_event )
Sorry, this is a bit convoluted, and wrong: if d->vcpu != NULL it will return -EINVAL even if d->vcpu[0]->arch.vm_event is NULL. I'll rework it. Apologies for the noise. Thanks, Razvan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel