On 01/01/14 04:35, Konrad Rzeszutek Wilk wrote: > From: Mukesh Rathor <mukesh.rat...@oracle.com> > > In the bootup code for PVH we can trap cpuid via vmexit, so don't > need to use emulated prefix call. We also check for vector callback > early on, as it is a required feature. PVH also runs at default kernel > IOPL. > > Finally, pure PV settings are moved to a separate function that are > only called for pure PV, ie, pv with pvmmu. They are also #ifdef > with CONFIG_XEN_PVMMU. [...] > @@ -331,12 +333,15 @@ static void xen_cpuid(unsigned int *ax, unsigned int > *bx, > break; > } > > - asm(XEN_EMULATE_PREFIX "cpuid" > - : "=a" (*ax), > - "=b" (*bx), > - "=c" (*cx), > - "=d" (*dx) > - : "0" (*ax), "2" (*cx)); > + if (xen_pvh_domain()) > + native_cpuid(ax, bx, cx, dx); > + else > + asm(XEN_EMULATE_PREFIX "cpuid" > + : "=a" (*ax), > + "=b" (*bx), > + "=c" (*cx), > + "=d" (*dx) > + : "0" (*ax), "2" (*cx));
For this one off cpuid call it seems preferrable to me to use the emulate prefix rather than diverge from PV. > @@ -1431,13 +1449,18 @@ asmlinkage void __init xen_start_kernel(void) > > xen_domain_type = XEN_PV_DOMAIN; > > + xen_setup_features(); > + xen_pvh_early_guest_init(); > xen_setup_machphys_mapping(); > > /* Install Xen paravirt ops */ > pv_info = xen_info; > pv_init_ops = xen_init_ops; > - pv_cpu_ops = xen_cpu_ops; > pv_apic_ops = xen_apic_ops; > + if (xen_pvh_domain()) > + pv_cpu_ops.cpuid = xen_cpuid; > + else > + pv_cpu_ops = xen_cpu_ops; If cpuid is trapped for PVH guests why does PVH need non-native cpuid op? David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
