Xen happens to be not vulnerable to PBRSB, but it turns out we can improve the performance on all eIBRS systems.
Andrew Cooper (2): x86/spec-ctrl: Enumeration for PBRSB_NO x86/spec-ctrl: Reduce HVM RSB overhead where possible xen/arch/x86/hvm/vmx/entry.S | 1 + xen/arch/x86/hvm/vmx/vmx.c | 20 ++++++- xen/arch/x86/include/asm/cpufeatures.h | 1 + xen/arch/x86/include/asm/msr-index.h | 1 + xen/arch/x86/msr.c | 5 +- xen/arch/x86/spec_ctrl.c | 106 +++++++++++++++++++++++++++++++-- 6 files changed, 126 insertions(+), 8 deletions(-) -- 2.11.0
