On 15/11/2016 19:01, Greg Kurz wrote: > On Tue, 15 Nov 2016 16:07:40 +0100 > Laurent Vivier <lviv...@redhat.com> wrote: > >> 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). >> > > You're talking about the '"kvm" accelerator not found' error ?
Yes > >> But I think postcopy is typically something we should test with KVM, not >> TCG, as there are some kernel dependencies (USERFAULTFD). >> > > I agree it should be tested with KVM when applicable but I don't understand > the 'not TCG' since it is the only way to test when you don't have access > to specific hardware... I agree; What I mean is we must test this preferably with KVM because it is more likely to have a problem with KVM than with TCG because of the MMU virtualization. >> It has been suggested a while to use an environment variable, like for >> kvm-unit-tests, something like QTEST_ACCEL="kvm". >> > > Yeah, I think it would be better than "-accel kvm:tcg" > >> Laurent > > Cheers. > > -- > Greg Thanks, Laurent
