Messages in this thread | | | Date | Thu, 1 Jun 2023 16:11:46 -0700 | Subject | Re: [PATCH v2 3/3] KVM: selftests: Add test for race in kvm_recalculate_apic_map() | From | Sean Christopherson <> |
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On Fri, May 26, 2023, Sean Christopherson wrote: > From: Michal Luczaj <mhal@rbox.co> > > Keep switching between LAPIC_MODE_X2APIC and LAPIC_MODE_DISABLED during > APIC map construction to hunt for TOCTOU bugs in KVM. KVM's optimized map > recalc makes multiple passes over the list of vCPUs, and the calculations > ignore vCPU's whose APIC is hardware-disabled, i.e. there's a window where > toggling LAPIC_MODE_DISABLED is quite interesting. > > Signed-off-by: Michal Luczaj <mhal@rbox.co> > Co-developed-by: Sean Christopherson <seanjc@google.com> > Signed-off-by: Sean Christopherson <seanjc@google.com> > --- > tools/testing/selftests/kvm/Makefile | 1 + > .../kvm/x86_64/recalc_apic_map_race.c | 76 +++++++++++++++++++ > 2 files changed, 77 insertions(+) > create mode 100644 tools/testing/selftests/kvm/x86_64/recalc_apic_map_race.c
Since there's another bug+test related to kvm_recalculate_apic_map()[*], I think it makes sense to name this recalc_apic_map_test, and then fold the LDR test into this one. The LDR test is tiny enough that I don't think it's worth a separate binary, even though I generally prefer to keep the selftests small.
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