v2->v3 changelogs: - use a bitmap to get/set the capability of bus lock detection. we support exit and off mode currently. - put the handle of exiting to userspace in vmx.c, thus no need to define a shadow to track vmx->exit_reason.bus_lock_detected. - remove the vcpu->stats.bus_locks since every bus lock exits to userspace. --- Add the support for bus lock VM exit in KVM. It is a sub-feature of bus lock detection and the detailed info can be found in the patch 2/2. In this patch series, the first patch applies Sean's refactor to vcpu_vmx.exit_reason available at https://patchwork.kernel.org/patch/11500659. It is necessary as bus lock VM exit adds a new modifier bit(bit 26) in exit_reason field in VMCS. The second patch is the enabling work for bus lock VM exit. Add the support to set the capability to enable bus lock vm exit. The current implementation just exit to user space when handling the bus lock detected in guest. The concrete throttling policy in user space still needs to be discussed. We can enforce ratelimit on bus lock in guest, just inject some sleep time, or maybe other ideas. Document for Bus Lock Detection is now available at the latest "Intel Architecture Instruction Set Extensions Programming Reference" (see below). Note that the section 9.1 for Bus Lock Debug Exception requires modification due to the feedback from kernel community: https://lore.kernel.org/lkml/87r1stmi1x.fsf@xxxxxxxxxxxxxxxxxxxxxxx/ Document Link: https://software.intel.com/content/www/us/en/develop/download/intel-architecture-instruction-set-extensions-programming-reference.html Chenyi Qiang (1): KVM: VMX: Enable bus lock VM exit Sean Christopherson (1): KVM: VMX: Convert vcpu_vmx.exit_reason to a union arch/x86/include/asm/kvm_host.h | 5 ++ arch/x86/include/asm/vmx.h | 1 + arch/x86/include/asm/vmxfeatures.h | 1 + arch/x86/include/uapi/asm/kvm.h | 1 + arch/x86/include/uapi/asm/vmx.h | 4 +- arch/x86/kvm/vmx/capabilities.h | 6 ++ arch/x86/kvm/vmx/nested.c | 42 ++++++++---- arch/x86/kvm/vmx/vmx.c | 106 ++++++++++++++++++++--------- arch/x86/kvm/vmx/vmx.h | 25 ++++++- arch/x86/kvm/x86.c | 27 +++++++- arch/x86/kvm/x86.h | 5 ++ include/uapi/linux/kvm.h | 7 ++ 12 files changed, 179 insertions(+), 51 deletions(-) -- 2.17.1
