This patch series enables the Last Branch Recording feature for the guest. Instead of trapping each LBR stack MSR access, the MSRs are passthroughed to the guest. Those MSRs are switched (i.e. load and saved) on VMExit and VMEntry. Test: Try "perf record -b ./test_program" on guest. Wei Wang (4): KVM/vmx: re-write the msr auto switch feature KVM/vmx: auto switch MSR_IA32_DEBUGCTLMSR perf/x86: add a function to get the lbr stack KVM/vmx: enable lbr for the guest arch/x86/events/intel/lbr.c | 23 +++++++ arch/x86/include/asm/perf_event.h | 14 ++++ arch/x86/kvm/vmx.c | 135 +++++++++++++++++++++++++++++++++----- 3 files changed, 154 insertions(+), 18 deletions(-) -- 2.7.4
