[PATCH 0/2] KVM: selftests: Fix sync_regs race tests on AMD

From: Sean Christopherson
Date: Thu Aug 17 2023 - 19:35:16 EST


The recently introduced sync_regs subtests to detect TOCTOU bugs hang on
AMD because KVM synthesizes INIT on triple fault shutdown (because AMD says
the VMCB is undefined after shutdown). Fix it by loading known good state
if a shutdown occurs.

Patch two explicitly injects #UD as the "good" vector so that the test
doesn't rely on KVM inadvertantly setting the vector to #DE (old, buggy
behavior).

Sean Christopherson (2):
KVM: selftests: Reload "good" vCPU state if vCPU hits shutdown
KVM: selftests: Explicit set #UD when *potentially* injecting
exception

.../selftests/kvm/x86_64/sync_regs_test.c | 17 ++++++++++++++++-
1 file changed, 16 insertions(+), 1 deletion(-)


base-commit: b6d40d24bb2eae6d4c2d4799ddbffcf7bae663db
--
2.42.0.rc1.204.g551eb34607-goog