| Message ID | 20151016153356.28104.48612.stgit@gimli.home |
|---|---|
| State | New |
| Headers | show |
On 16/10/2015 17:38, Alex Williamson wrote: > According to Microsoft documentation, the signature in the standard > hypervisor CPUID leaf at 0x40000000 identifies the Vendor ID and is > for reporting and diagnostic purposes only. We can therefore allow > the user to change it to whatever they want, within the 12 character > limit. Add a new hyperv-vendor-id option to the -cpu flag to allow > for this, ex: > > -cpu host,hv_time,hv_vendor_id=KeenlyKVM > > Link: http://msdn.microsoft.com/library/windows/hardware/hh975392 > Signed-off-by: Alex Williamson <alex.williamson@redhat.com> > --- > > v2: Replace abort() with truncating the string, error report updated > > Igor also had the idea of creating a DEFINE_PROP_STRING_LEN property > where we could enforce the length earlier in the parameter checking. > If we like that idea, we probably need to do it first since we don't > want to switch from truncating to erroring between releases. I can > work on that if preferred. Thanks, I applied this one, because the truncation matches what is done in other places (ACPI tables, SCSI product/vendor, etc.) Paolo
diff --git a/target-i386/cpu-qom.h b/target-i386/cpu-qom.h index c35b624..6c1eaaa 100644 --- a/target-i386/cpu-qom.h +++ b/target-i386/cpu-qom.h @@ -88,6 +88,7 @@ typedef struct X86CPU { bool hyperv_vapic; bool hyperv_relaxed_timing; int hyperv_spinlock_attempts; + char *hyperv_vendor_id; bool hyperv_time; bool hyperv_crash; bool check_cpuid; diff --git a/target-i386/cpu.c b/target-i386/cpu.c index 05d7f26..71df546 100644 --- a/target-i386/cpu.c +++ b/target-i386/cpu.c @@ -3146,6 +3146,7 @@ static Property x86_cpu_properties[] = { DEFINE_PROP_UINT32("level", X86CPU, env.cpuid_level, 0), DEFINE_PROP_UINT32("xlevel", X86CPU, env.cpuid_xlevel, 0), DEFINE_PROP_UINT32("xlevel2", X86CPU, env.cpuid_xlevel2, 0), + DEFINE_PROP_STRING("hv-vendor-id", X86CPU, hyperv_vendor_id), DEFINE_PROP_END_OF_LIST() }; diff --git a/target-i386/kvm.c b/target-i386/kvm.c index 80d1a7e..9d25fd7 100644 --- a/target-i386/kvm.c +++ b/target-i386/kvm.c @@ -490,7 +490,19 @@ int kvm_arch_init_vcpu(CPUState *cs) if (hyperv_enabled(cpu)) { c = &cpuid_data.entries[cpuid_i++]; c->function = HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS; - memcpy(signature, "Microsoft Hv", 12); + if (!cpu->hyperv_vendor_id) { + memcpy(signature, "Microsoft Hv", 12); + } else { + size_t len = strlen(cpu->hyperv_vendor_id); + + if (len > 12) { + fprintf(stderr, + "hyperv-vendor-id too long, truncated to 12 charaters"); + len = 12; + } + memset(signature, 0, 12); + memcpy(signature, cpu->hyperv_vendor_id, len); + } c->eax = HYPERV_CPUID_MIN; c->ebx = signature[0]; c->ecx = signature[1];
According to Microsoft documentation, the signature in the standard hypervisor CPUID leaf at 0x40000000 identifies the Vendor ID and is for reporting and diagnostic purposes only. We can therefore allow the user to change it to whatever they want, within the 12 character limit. Add a new hyperv-vendor-id option to the -cpu flag to allow for this, ex: -cpu host,hv_time,hv_vendor_id=KeenlyKVM Link: http://msdn.microsoft.com/library/windows/hardware/hh975392 Signed-off-by: Alex Williamson <alex.williamson@redhat.com> --- v2: Replace abort() with truncating the string, error report updated Igor also had the idea of creating a DEFINE_PROP_STRING_LEN property where we could enforce the length earlier in the parameter checking. If we like that idea, we probably need to do it first since we don't want to switch from truncating to erroring between releases. I can work on that if preferred. Thanks, Alex target-i386/cpu-qom.h | 1 + target-i386/cpu.c | 1 + target-i386/kvm.c | 14 +++++++++++++- 3 files changed, 15 insertions(+), 1 deletion(-)