Failure of troublesome vhost-user/flags-mismatch test can't be reproduce
From:
Coiby Xu
Subject:
Failure of troublesome vhost-user/flags-mismatch test can't be reproduced
Date:
Mon, 28 Oct 2019 10:57:09 +0800
Hi,
Can anyone reproduce the failure of one troublesome test vhost-user/flags-mismatch (https://wiki.qemu.org/Testing/CI/TroublesomeTests) which has been disabled since Aug 15 2017 (https://patchwork.kernel.org/patch/9939431/)? Last month I downloaded QEMU source code (commit ID: 3483534ec3) and this version also failed this test. After debugging this issue, I thought I have fixed this issue by saving acknowledged features after vhost backend disconnect with the client (qemu). But later I reviewed the commit history of net/vhost-user.c and found out this test failed on my machines because of a newly introduced bug from a recent commit (https://patchwork.kernel.org/patch/11054781/) on July 29 2019 and this new bug has already been fixed by a more recent commit (https://lists.sr.ht/~philmd/qemu/%3C20190924162044.11414-1-amorenoz%40redhat.com%3E). After more investigation, it surprised me both 3.1.0 and 2.9.1could pass vhost-user/flags-mismatch test. According to the comments on the commit https://patchwork.kernel.org/patch/9939431/ which disabled the vhost-user/flags-mismatch and other two tests, it seems the tests are only broken on travis. Maybe we should re-investigate this issue to re-enable the test so similar bugs like https://bugzilla.redhat.com/show_bug.cgi?id=1738768 could be prevented in the first place.
Btw we can excluisvely check this test on latest QEMU by given TESTPATH and setting QTEST_VHOST_USER_FIXME environment variable,