Wei Liu <wei.liu@xxxxxxxxxx> writes: > Microsoft Hypervisor requires the root partition to make a few > hypercalls to setup application processors before they can be used. > > Signed-off-by: Lillian Grassin-Drake <ligrassi@xxxxxxxxxxxxx> > Signed-off-by: Sunil Muthuswamy <sunilmut@xxxxxxxxxxxxx> > Co-Developed-by: Lillian Grassin-Drake <ligrassi@xxxxxxxxxxxxx> > Co-Developed-by: Sunil Muthuswamy <sunilmut@xxxxxxxxxxxxx> > Signed-off-by: Wei Liu <wei.liu@xxxxxxxxxx> > --- > CPU hotplug and unplug is not yet supported in this setup, so those > paths remain untouched. > --- > arch/x86/kernel/cpu/mshyperv.c | 27 +++++++++++++++++++++++++++ > 1 file changed, 27 insertions(+) > > diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c > index 1bf57d310f78..7522cae02759 100644 > --- a/arch/x86/kernel/cpu/mshyperv.c > +++ b/arch/x86/kernel/cpu/mshyperv.c > @@ -203,6 +203,31 @@ static void __init hv_smp_prepare_boot_cpu(void) > hv_init_spinlocks(); > #endif > } > + > +static void __init hv_smp_prepare_cpus(unsigned int max_cpus) > +{ > +#if defined(CONFIG_X86_64) I think it makes little sense to try to make Linux work as Hyper-V root partition when !CONFIG_X86_64. If we still care about Hyper-V enablement for !CONFIG_X86_64 we can probably introduce something like CONFIG_HYPERV_ROOT and enable it automatically, e.g. config HYPERV_ROOT def_bool HYPERV && X86_64 and use it instead. > + int i; > + int vp_index = 1; > + int ret; > + > + native_smp_prepare_cpus(max_cpus); > + > + for_each_present_cpu(i) { > + if (i == 0) > + continue; > + ret = hv_call_add_logical_proc(numa_cpu_node(i), i, cpu_physical_id(i)); > + BUG_ON(ret); > + } > + > + for_each_present_cpu(i) { > + if (i == 0) > + continue; > + ret = hv_call_create_vp(numa_cpu_node(i), hv_current_partition_id, vp_index++, i); So vp_index variable is needed here to make sure there are no gaps? (or we could've just used 'i')? > + BUG_ON(ret); > + } > +#endif > +} > #endif > > static void __init ms_hyperv_init_platform(void) > @@ -359,6 +384,8 @@ static void __init ms_hyperv_init_platform(void) > > # ifdef CONFIG_SMP > smp_ops.smp_prepare_boot_cpu = hv_smp_prepare_boot_cpu; > + if (hv_root_partition) > + smp_ops.smp_prepare_cpus = hv_smp_prepare_cpus; > # endif > > /* -- Vitaly _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization