On 17/04/20 23:55, Babu Moger wrote: > CPUID leaf CPUID_Fn80000008_ECX provides information about the > number of threads supported by the processor. It was found that > the field ApicIdSize(bits 15-12) was not set correctly. > > ApicIdSize is defined as the number of bits required to represent > all the ApicId values within a package. > > Valid Values: Value Description > 3h-0h Reserved. > 4h up to 16 threads. > 5h up to 32 threads. > 6h up to 64 threads. > 7h up to 128 threads. > Fh-8h Reserved. > > Fix the bit appropriately. > > This came up during following thread. > https://lore.kernel.org/qemu-devel/158643709116.17430.15995069125716778943.malone...@wampee.canonical.com/#t > > Refer the Processor Programming Reference (PPR) for AMD Family 17h > Model 01h, Revision B1 Processors. The documentation is available > from the bugzilla Link below. > Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 > > Reported-by: Philipp Eppelt <1871...@bugs.launchpad.net> > Signed-off-by: Babu Moger <babu.mo...@amd.com> > --- > v2: > Used env->pkg_offset for bits 15:12 which is already available. > > target/i386/cpu.c | 15 ++++++++++++--- > 1 file changed, 12 insertions(+), 3 deletions(-) > > diff --git a/target/i386/cpu.c b/target/i386/cpu.c > index 90ffc5f..5e5a605 100644 > --- a/target/i386/cpu.c > +++ b/target/i386/cpu.c > @@ -5830,11 +5830,20 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, > uint32_t count, > *eax = cpu->phys_bits; > } > *ebx = env->features[FEAT_8000_0008_EBX]; > - *ecx = 0; > - *edx = 0; > if (cs->nr_cores * cs->nr_threads > 1) { > - *ecx |= (cs->nr_cores * cs->nr_threads) - 1; > + /* > + * Bits 15:12 is "The number of bits in the initial > + * Core::X86::Apic::ApicId[ApicId] value that indicate > + * thread ID within a package". This is already stored at > + * CPUX86State::pkg_offset. > + * Bits 7:0 is "The number of threads in the package is NC+1" > + */ > + *ecx = (env->pkg_offset << 12) | > + ((cs->nr_cores * cs->nr_threads) - 1); > + } else { > + *ecx = 0; > } > + *edx = 0; > break; > case 0x8000000A: > if (env->features[FEAT_8000_0001_ECX] & CPUID_EXT3_SVM) { >
Queued, thanks. Paolo