On Wed, Feb 10, 2021, Paolo Bonzini wrote: > On 10/02/21 19:26, Sean Christopherson wrote: > > Fix a '40' vs '0x40' bug in the new Xen shinfo selftest, and clean up some > > other oddities that made root causing the problem far more painful than it > > needed to be. > > > > Note, Paolo already queued a patch from Vitaly that adds the tests to > > .gitignore[*], i.e. patch 01 can likely be dropped. I included it here > > for completeness. > > > > [*] https://lkml.kernel.org/r/20210129161821.74635-1-vkuznets@xxxxxxxxxx > > > > Sean Christopherson (5): > > KVM: selftests: Ignore recently added Xen tests' build output > > KVM: selftests: Fix size of memslots created by Xen tests > > KVM: selftests: Fix hex vs. decimal snafu in Xen test > > KVM: sefltests: Don't bother mapping GVA for Xen shinfo test > > KVM: x86/xen: Explicitly pad struct compat_vcpu_info to 64 bytes > > > > arch/x86/kvm/xen.h | 11 ++++++----- > > tools/testing/selftests/kvm/.gitignore | 2 ++ > > tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c | 12 +++++------- > > tools/testing/selftests/kvm/x86_64/xen_vmcall_test.c | 3 +-- > > 4 files changed, 14 insertions(+), 14 deletions(-) > > > > Stupid question: how did you notice that? In other words what broke for you > and not for me? I assume sheer dumb luck? The test checks a single bit, so there's a 50/50 chance it will pass if whatever it's reading is non-zero. If my math is correct (big if), the net effect is that the check was against pvclock_vcpu_time_info.tsc_to_system_mul, which on my VM where I'm running the test is always 0xcd4681c9. ==== Test Assertion Failure ==== x86_64/xen_shinfo_test.c:161: ti->version && !(ti->version & 1) pid=1236 tid=1236 - Interrupted system call 1 0x0000000000401623: main at xen_shinfo_test.c:160 2 0x00007f303e261bf6: ?? ??:0 3 0x00000000004016f9: _start at ??:? Bad time_info version cd4681c9
