On 15/11/2016 16:03, Greg Kurz wrote: > On Tue, 15 Nov 2016 14:48:30 +0000 > Stefan Hajnoczi <stefa...@gmail.com> wrote: > >> On Tue, Nov 15, 2016 at 01:58:38PM +0100, Laurent Vivier wrote: >>> >>> >>> On 15/11/2016 13:20, Dr. David Alan Gilbert wrote: >>>> * Stefan Hajnoczi (stefa...@gmail.com) wrote: >>>>> On Tue, Nov 15, 2016 at 10:09 AM, Greg Kurz <gr...@kaod.org> wrote: >>>>>> On Tue, 15 Nov 2016 10:53:35 +0100 >>>>>> Laurent Vivier <lviv...@redhat.com> wrote: >>>>>> >>>>>>> On 14/11/2016 21:52, Stefan Hajnoczi wrote: >>>>>>>> I hit a failure running "make check" on ppc64 for the first time. >>>>>>>> Ideas? >>>>>>>> >>>>>>>> Stefan >>>>>>>> >>>>>>>> commit 682df581c65ed2c1b9e77093e332214ecaa1ee93 >>>>>>>> >>>>>>>> GTESTER check-qtest-ppc64 >>>>>>>> Memory content inconsistency at 5af4000 first_byte = 1b last_byte = 1a >>>>>>>> current = 7c hit_edge = 1 >>>>>>>> Memory content inconsistency at 5af5000 first_byte = 1b last_byte = 7c >>>>>>>> current = 1b hit_edge = 1 >>>>>>>> Memory content inconsistency at 5e59000 first_byte = 1b last_byte = 1b >>>>>>>> current = 1a hit_edge = 1 >>>>>>>> ** >>>>>>>> ERROR:tests/postcopy-test.c:345:check_guests_ram: 'bad' should be FALSE >>>>>>>> GTester: last random seed: R02S9d79166a1ca7e21940a0f4b0b1255d5b >>>>>>>> >>>>>>> >>>>>>> Are you using KVM PR? >>>>>>> >>>>>>> it was working fine with TCG and KVM HV. >>>>>>> >>>>>>> Apparently, USERFAULTFD doesn't work with KVM PR. >>>>>>> >>>>>>> I've already seen this kind of error with nested KVM on Power: >>>>>>> guest in guest with KVM PR in host. >>>>>>> >>>>>>> This problem was reported on IRC by Greg if I remember correctly (CC:) >>>>>>> >>>>>> >>>>>> Yeah I hit this when running make check in a PPC64 BE guest which >>>>>> has kvm_pr loaded. I did not find time to investigate though... I've >>>>>> switched to run make check on bare metal POWER7 instead. >>>>> >>>>> Right, it's POWER7 PPC64 BE with kvm_pr. >>>>> >>>>> If this should be fixed for QEMU 2.8 please add it to >>>>> http://qemu-project.org/Planning/2.8 and I'll track it (i.e. won't >>>>> release before it's resolved). >>>>> >>>>> If this is a known issue that will be in QEMU 2.8 please add it to >>>>> http://qemu-project.org/ChangeLog/2.8#Known_issues. >>>> >>>> I don't think it's new with 2.8 (Laurent?) and I think it's actually >>>> a kernel issue that needs fixing. >>> >>> I's not a regression and I think it's a kernel issue. >>> >>> As it has never worked with KVM PR and can't be fixed at QEMU level, we >>> can't solve it for 2.8 (no tracking). >>> >>> I'm going to update the know issues for 2.8. >>> [and I'm going to try to understand what really happens] >> >> Should the test be skipped on KVM PR? >> >> It's a shame that make check fails. >> > > Yeah I agree this is lame but KVM PR isn't very cherished these days... > > Since postcopy-test runs QEMU with -accel kvm:tcg, a possible workaround is > to kick KVM out of the environment you're running make check in.
Moreover, using "-accel kvm:tcg" induces an error when the test is running in cross-arch case (ppc on intel, or intel on ppc). But I think postcopy is typically something we should test with KVM, not TCG, as there are some kernel dependencies (USERFAULTFD). It has been suggested a while to use an environment variable, like for kvm-unit-tests, something like QTEST_ACCEL="kvm". Laurent
