Fix a bug where KVM injects a bogus #UD for SEV guests when trying to skip an INT3 as part of re-injecting the associated #BP that got kinda sorta intercepted due to a #NPF occuring while vectoring/delivering the #BP. Patch 1 is the main fix. It's a little ugly, but suitable for backporting. Patch 2 is a tangentially related cleanup to make NRIPS a requirement for enabling SEV, e.g. so that we don't ever get "bug" reports of SEV guests not working when NRIPS is disabled. Patches 3 and 4 clean up the hack from patch 1, but are most definitely not stable material (hence the slightly ugly fix). Verified the original bug by toggling the NX hugepage mitigation to force a #NPF when devliering #BP in the guest. v2: - Actually fix the bug. [Tom] - Do the bigger cleanup I avoided in v1. v1: https://lore.kernel.org/all/20230810234919.145474-1-seanjc@xxxxxxxxxx Sean Christopherson (4): KVM: SVM: Don't inject #UD if KVM attempts to skip SEV guest insn KVM: SVM: Require nrips support for SEV guests (and beyond) KVM: x86: Refactor can_emulate_instruction() return to be more expressive KVM: SVM: Treat all "skip" emulation for SEV guests as outright failures arch/x86/include/asm/kvm-x86-ops.h | 2 +- arch/x86/include/asm/kvm_host.h | 4 +-- arch/x86/kvm/svm/sev.c | 2 +- arch/x86/kvm/svm/svm.c | 55 +++++++++++++++++------------- arch/x86/kvm/svm/svm.h | 1 + arch/x86/kvm/vmx/vmx.c | 12 +++---- arch/x86/kvm/x86.c | 22 ++++++++---- 7 files changed, 58 insertions(+), 40 deletions(-) base-commit: fff2e47e6c3b8050ca26656693caa857e3a8b740 -- 2.42.0.rc2.253.gd59a3bf2b4-goog
