Ping. On Thu, Jul 11, 2019 at 08:58:28AM -0700, Sean Christopherson wrote: > Debugging VM-Enter failures has been the bane of my existence for years. > Seeing KVM's VMCS dump format pop up on a console triggers a Pavlovian > response of swear words and sighs. As KVM's coverage of VM-Enter checks > improve, so too do the odds of being able to triage/debug a KVM (or any > other hypervisor) bug by running the bad KVM build as an L1 guest. > > Improve support for using KVM to debug a buggy VMM by adding tracepoints > to capture the basic gist of a VM-Enter failure so that extracting said > information from KVM doesn't require attaching a debugger or modifying > L0 KVM to manually log failures. > > The captured information is by no means complete or perfect, e.g. I'd > love to capture *exactly* why a consistency check failed, but logging > that level of detail would require invasive code changes and might even > act as a deterrent to adding more checks in KVM. > > v3: Fix a minor snafu in the v2 rebase, and re-rebase to kvm/next > (a45ff5994c9c, "Merge tag 'kvm-arm-for-5.3'...") > > v2: Rebase to kvm/queue. > > Sean Christopherson (2): > KVM: nVMX: add tracepoint for failed nested VM-Enter > KVM: nVMX: trace nested VM-Enter failures detected by H/W > > arch/x86/include/asm/vmx.h | 14 ++ > arch/x86/kvm/trace.h | 22 +++ > arch/x86/kvm/vmx/nested.c | 269 ++++++++++++++++++++----------------- > arch/x86/kvm/x86.c | 1 + > 4 files changed, 179 insertions(+), 127 deletions(-) > > -- > 2.22.0 >
