This series re-works the SVM KVM implementation to use vmload/vmsave to handle saving/restoring additional host MSRs rather than explicit MSR read/writes, resulting in a significant performance improvement for some specific workloads and simplifying some of the save/load code (PATCH 1). With those changes some commonalities emerge between SEV-ES and normal vcpu_load/vcpu_put paths, which we then take advantage of to share more code, as well as refactor them in a way that more closely aligns with the VMX implementation (PATCH 2 and 3). v3: - rebased on kvm-next - remove uneeded braces from host MSR save/load loops (Sean) - use page_to_phys() in place of page_to_pfn() and shifting (Sean) - use stack instead of struct field to cache host save area outside of per-cpu storage, and pass as an argument to __svm_vcpu_run() to handle the VMLOAD in ASM code rather than inlining ASM (Sean/Andy) - remove now-uneeded index/sev_es_restored fields from host_save_user_msrs list - move host-saving/guest-loading of registers to prepare_guest_switch(), and host-loading of registers to prepare_host_switch, for both normal and sev-es paths (Sean) v2: - rebase on latest kvm/next - move VMLOAD to just after vmexit so we can use it to handle all FS/GS host state restoration and rather than relying on loadsegment() and explicit write to MSR_GS_BASE (Andy) - drop 'host' field from struct vcpu_svm since it is no longer needed for storing FS/GS/LDT state (Andy) arch/x86/kvm/svm/sev.c | 30 +----------------------------- arch/x86/kvm/svm/svm.c | 112 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++------------------------------------------------------ arch/x86/kvm/svm/svm.h | 31 ++++++------------------------- arch/x86/kvm/svm/vmenter.S | 10 ++++++++++ 4 files changed, 75 insertions(+), 108 deletions(-)
