Hi Igor, On 2/22/19 1:45 PM, Igor Mammedov wrote: > On Wed, 20 Feb 2019 23:39:54 +0100 > Eric Auger <eric.au...@redhat.com> wrote: > >> This patch implements the machine class kvm_type() callback. >> It returns the number of bits requested to implement the whole GPA >> range including the RAM and IO regions located beyond. >> The returned value in passed though the KVM_CREATE_VM ioctl and >> this allows KVM to set the stage2 tables dynamically. >> >> Signed-off-by: Eric Auger <eric.au...@redhat.com> >> >> --- >> >> v6 -> v7: >> - Introduce RAMBASE and rename add LEGACY_ prefix in that patch >> - use local variables with explicit names in virt_set_memmap: >> device_memory_base, device_memory_size >> - add an extended_memmap field in the class >> >> v5 -> v6: >> - add some comments >> - high IO region cannot start before 256GiB >> --- >> hw/arm/virt.c | 50 ++++++++++++++++++++++++++++++++++++++++++- >> include/hw/arm/virt.h | 2 ++ >> 2 files changed, 51 insertions(+), 1 deletion(-) >> >> diff --git a/hw/arm/virt.c b/hw/arm/virt.c >> index 9db602457b..ad3a0ad73d 100644 >> --- a/hw/arm/virt.c >> +++ b/hw/arm/virt.c >> @@ -1437,7 +1437,14 @@ static void machvirt_init(MachineState *machine) >> bool firmware_loaded = bios_name || drive_get(IF_PFLASH, 0, 0); >> bool aarch64 = true; >> >> - virt_set_memmap(vms); >> + /* >> + * In accelerated mode, the memory map is computed in kvm_type(), >> + * if set, to create a VM with the right number of IPA bits. >> + */ >> + >> + if (!mc->kvm_type || !kvm_enabled()) { >> + virt_set_memmap(vms); >> + } >> >> /* We can probe only here because during property set >> * KVM is not available yet >> @@ -1814,6 +1821,36 @@ static HotplugHandler >> *virt_machine_get_hotplug_handler(MachineState *machine, >> return NULL; >> } >> >> +/* >> + * for arm64 kvm_type [7-0] encodes the requested number of bits >> + * in the IPA address space >> + */ >> +static int virt_kvm_type(MachineState *ms, const char *type_str) >> +{ >> + VirtMachineState *vms = VIRT_MACHINE(ms); >> + int max_vm_pa_size = kvm_arm_get_max_vm_ipa_size(ms); >> + int requested_pa_size; >> + >> + /* we freeze the memory map to compute the highest gpa */ >> + virt_set_memmap(vms); >> + >> + requested_pa_size = 64 - clz64(vms->highest_gpa); >> + >> + if (requested_pa_size > max_vm_pa_size) { >> + error_report("-m and ,maxmem option values " >> + "require an IPA range (%d bits) larger than " >> + "the one supported by the host (%d bits)", >> + requested_pa_size, max_vm_pa_size); >> + exit(1); >> + } >> + /* >> + * By default we return 0 which corresponds to an implicit legacy >> + * 40b IPA setting. Otherwise we return the actual requested PA >> + * logsize >> + */ >> + return requested_pa_size > 40 ? requested_pa_size : 0; >> +} >> + >> static void virt_machine_class_init(ObjectClass *oc, void *data) >> { >> MachineClass *mc = MACHINE_CLASS(oc); >> @@ -1838,6 +1875,7 @@ static void virt_machine_class_init(ObjectClass *oc, >> void *data) >> mc->cpu_index_to_instance_props = virt_cpu_index_to_props; >> mc->default_cpu_type = ARM_CPU_TYPE_NAME("cortex-a15"); >> mc->get_default_cpu_node_id = virt_get_default_cpu_node_id; >> + mc->kvm_type = virt_kvm_type; >> assert(!mc->get_hotplug_handler); >> mc->get_hotplug_handler = virt_machine_get_hotplug_handler; >> hc->plug = virt_machine_device_plug_cb; >> @@ -1909,6 +1947,12 @@ static void virt_instance_init(Object *obj) >> "Valid values are none and smmuv3", >> NULL); >> >> + if (vmc->no_extended_memmap) { >> + vms->extended_memmap = false; >> + } else { >> + vms->extended_memmap = true; >> + } >> + >> vms->irqmap = a15irqmap; >> } >> >> @@ -1939,8 +1983,12 @@ DEFINE_VIRT_MACHINE_AS_LATEST(4, 0) >> >> static void virt_machine_3_1_options(MachineClass *mc) >> { >> + VirtMachineClass *vmc = VIRT_MACHINE_CLASS(OBJECT_CLASS(mc)); >> virt_machine_4_0_options(mc); >> compat_props_add(mc->compat_props, hw_compat_3_1, hw_compat_3_1_len); >> + >> + /* extended memory map is enabled from 4.0 onwards */ >> + vmc->no_extended_memmap = true; > That's probably was asked in v6, > do we really need this knob? Yes the point was raised by Peter and I replied by another question ;-) " But don't we want to forbid any pre-4.0 machvirt to run with more than 255GiB RAM? " without this knob: - pre-4.0 machines will gain the capability to support more than 255GB initial RAM if the kernel supports dynamic IPA setting - pre-4.0 machines will gain PCDIMM/NVDIMM support - another concern, maxmem and slots were not checked previously. If for some reason - without instantiating the actual slots -, the user specified it this was previously ignored. Now this is not anymore as both parameters allow to compute the requested IPA range. So this may fail now. So I thought this was clearer to disable all the above for pre-4.0 machines. However if both of you agree, I will remove it.
thanks Eric > >> } >> DEFINE_VIRT_MACHINE(3, 1) >> >> diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h >> index acad0400d8..7798462cb0 100644 >> --- a/include/hw/arm/virt.h >> +++ b/include/hw/arm/virt.h >> @@ -106,6 +106,7 @@ typedef struct { >> bool claim_edge_triggered_timers; >> bool smbios_old_sys_ver; >> bool no_highmem_ecam; >> + bool no_extended_memmap; >> } VirtMachineClass; >> >> typedef struct { >> @@ -135,6 +136,7 @@ typedef struct { >> hwaddr highest_gpa; >> hwaddr device_memory_base; >> hwaddr device_memory_size; >> + bool extended_memmap; >> } VirtMachineState; >> >> #define VIRT_ECAM_ID(high) (high ? VIRT_HIGH_PCIE_ECAM : VIRT_PCIE_ECAM) >