QEMU iotest 267 failure / assertion in migration code

[Thomas Huth <thuth@redhat.com>]

  Hi!

I just ran "make check" in a build directory where I did
not compile qemu-system-x86_64, and got a failure with
iotest 267.

Re-running the "check" script directly got me some more
information:

$ ./check -qcow2 267
QEMU          -- "/tmp/qemu/tests/qemu-iotests/../../qemu-system-alpha" -nodefaults -display none -accel qtest
QEMU_IMG      -- "/tmp/qemu/tests/qemu-iotests/../../qemu-img"
QEMU_IO       -- "/tmp/qemu/tests/qemu-iotests/../../qemu-io" --cache writeback --aio threads -f qcow2
QEMU_NBD      -- "/tmp/qemu/tests/qemu-iotests/../../qemu-nbd"
IMGFMT        -- qcow2
IMGPROTO      -- file
PLATFORM      -- Linux/x86_64 thuth 4.18.0-425.3.1.el8.x86_64
TEST_DIR      -- /tmp/qemu/tests/qemu-iotests/scratch
SOCK_DIR      -- /tmp/tmp_qbcjhsu
GDB_OPTIONS   --
VALGRIND_QEMU --
PRINT_QEMU_OUTPUT --

267   fail       [18:39:41] [18:39:44]   3.5s                 output mismatch (see /tmp/qemu/tests/qemu-iotests/scratch/267.out.bad)
--- .../qemu/tests/qemu-iotests/267.out
+++ /tmp/qemu/tests/qemu-iotests/scratch/267.out.bad
@@ -31,23 +31,23 @@
  Testing: -drive driver=IMGFMT,file=TEST_DIR/t.IMGFMT,if=none
  QEMU X.Y.Z monitor - type 'help' for more information
  (qemu) savevm snap0
-(qemu) info snapshots
-List of snapshots present on all disks:
-ID        TAG               VM SIZE                DATE     VM CLOCK     ICOUNT
---        snap0                SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
-(qemu) loadvm snap0
-(qemu) quit
+QEMU_PROG: ../../qemu/migration/ram.c:874: pss_find_next_dirty: Assertion `pss->host_page_end' failed.
+./common.rc: line 181: 1903770 Aborted                 (core dumped) ( if [ -n "${QEMU_NEED_PID}" ]; then
+    echo $BASHPID > "${QEMU_TEST_DIR}/qemu-${_QEMU_HANDLE}.pid";
+fi; GDB=""; if [ -n "${GDB_OPTIONS}" ]; then
+    GDB="gdbserver ${GDB_OPTIONS}";
+fi; VALGRIND_QEMU="${VALGRIND_QEMU_VM}" _qemu_proc_exec "${VALGRIND_LOGFILE}" $GDB "$QEMU_PROG" $QEMU_OPTIONS "$@" )


Looks like this test does not work if the main machine
of the selected QEMU binary does not support migration?

Should we remove this test from the "auto" group?

Anyway, QEMU should also not trigger an assertion, so this
sounds like another bug?

  Thomas