Initial virtualization of Intel PT was added by making it as fixed feature set of ICX's capabilities. However, it breaks the Intel PT exposure on SPR machine because SPR has less PT capabilities of CPUID(0x14,1):EBX[15:0]. This series aims to make Intel PT configurable that named CPU model can define its own PT feature set and "-cpu host/max" can use host pass-through feature set of Intel PT. At the same time, it also ensures existing named CPU model to generate the same PT CPUID set as before to not break live migration. Changes in v3: - rebase to v7.2.0-rc4 - Add bit 7 and 8 of FEAT_14_0_EBX in Patch 3 v2: https://lore.kernel.org/qemu-devel/20220808085834.3227541-1-xiaoyao.li@xxxxxxxxx/ Changes in v2: - split out 3 patches (per Eduardo's comment) - determine if the named cpu model uses default Intel PT capabilities (to be compatible with the old behavior) by condition that all PT feature leaves are all zero. v1: https://lore.kernel.org/qemu-devel/20210909144150.1728418-1-xiaoyao.li@xxxxxxxxx/ Xiaoyao Li (8): target/i386: Print CPUID subleaf info for unsupported feature target/i386/intel-pt: Fix INTEL_PT_ADDR_RANGES_NUM_MASK target/i386/intel-pt: Introduce FeatureWordInfo for Intel PT CPUID leaf 0x14 target/i386/intel-pt: print special message for INTEL_PT_ADDR_RANGES_NUM target/i386/intel-pt: Rework/rename the default INTEL-PT feature set target/i386/intel-pt: Enable host pass through of Intel PT target/i386/intel-pt: Define specific PT feature set for IceLake-server and Snowridge target/i386/intel-pt: Access MSR_IA32_RTIT_ADDRn based on guest CPUID configuration target/i386/cpu.c | 293 +++++++++++++++++++++++++++++++----------- target/i386/cpu.h | 40 +++++- target/i386/kvm/kvm.c | 8 +- 3 files changed, 263 insertions(+), 78 deletions(-) -- 2.27.0