On 01/10/20 13:29, Maxim Levitsky wrote: > This is the next version of this patch series. > > In V5 I adopted Sean Christopherson's suggestion to make .set_efer return > a negative error (-ENOMEM in this case) which in most cases in kvm > propagates to the userspace. > > I noticed though that wrmsr emulation code doesn't do this and instead > it injects #GP to the guest on _any_ error. > > So I fixed the wrmsr code to behave in a similar way to the rest > of the kvm code. > (#GP only on a positive error value, and forward the negative error to > the userspace) > > I had to adjust one wrmsr handler (xen_hvm_config) to stop it from returning > negative values so that new WRMSR emulation behavior doesn't break it. > This patch was only compile tested. > > The memory allocation failure was tested by always returning -ENOMEM > from svm_allocate_nested. > > The nested allocation itself was tested by countless attempts to run > nested guests, do nested migration on both my AMD and Intel machines. > I wasn't able to break it. > > Changes from V5: addressed Sean Christopherson's review feedback. > Changes from V6: rebased the code on latest kvm/queue > > Best regards, > Maxim Levitsky > > Maxim Levitsky (4): > KVM: x86: xen_hvm_config: cleanup return values > KVM: x86: report negative values from wrmsr emulation to userspace > KVM: x86: allow kvm_x86_ops.set_efer to return an error value > KVM: nSVM: implement on demand allocation of the nested state > > arch/x86/include/asm/kvm_host.h | 2 +- > arch/x86/kvm/emulate.c | 4 +-- > arch/x86/kvm/svm/nested.c | 42 ++++++++++++++++++++++ > arch/x86/kvm/svm/svm.c | 64 ++++++++++++++++++--------------- > arch/x86/kvm/svm/svm.h | 10 +++++- > arch/x86/kvm/vmx/vmx.c | 6 ++-- > arch/x86/kvm/x86.c | 39 ++++++++++---------- > 7 files changed, 114 insertions(+), 53 deletions(-) > Queued, thanks. Paolo
