[PATCH 0/4] Verify dirty logging works properly with page stats

From: Mingwei Zhang
Date: Wed Mar 23 2022 - 14:49:30 EST


This patchset is to verify if dirty logging works properly by checking page
stats from the per-VM interface. We discovered one performance bug in
disallowed_hugepage_adjust() which prevents KVM from recovering large pages
for the guest. The selftest logic added later could help validate the
problem.

The patchset borrowes two patches come from Ben's series: "[PATCH 00/13]
KVM: x86: Add a cap to disable NX hugepages on a VM" [1], which completes the
selftest library functions to use the stats interface.

[1] https://lore.kernel.org/all/20220310164532.1821490-2-bgardon@xxxxxxxxxx/T/

Ben Gardon (2):
selftests: KVM: Dump VM stats in binary stats test
selftests: KVM: Test reading a single stat

Mingwei Zhang (2):
KVM: x86/mmu: explicitly check nx_hugepage in
disallowed_hugepage_adjust()
selftests: KVM: use dirty logging to check if page stats work
correctly

arch/x86/kvm/mmu/mmu.c | 14 +-
.../selftests/kvm/dirty_log_perf_test.c | 52 +++++
.../selftests/kvm/include/kvm_util_base.h | 2 +
.../selftests/kvm/kvm_binary_stats_test.c | 6 +
tools/testing/selftests/kvm/lib/kvm_util.c | 196 ++++++++++++++++++
5 files changed, 268 insertions(+), 2 deletions(-)

--
2.35.1.894.gb6a874cedc-goog