On 18.03.22 21:36, John Snow wrote:
Howdy,
Heya,
[...]
- Uh, actually, test 040 fails with this patchset and I don't understand
if it's intentional, harmless, a test design problem, or worse:
======================================================================
ERROR: test_filterless_commit (__main__.TestCommitWithFilters)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/home/jsnow/src/qemu/tests/qemu-iotests/040", line 822, in tearDown
self.do_test_io('read')
File "/home/jsnow/src/qemu/tests/qemu-iotests/040", line 751, in do_test_io
qemu_io('-f', iotests.imgfmt,
File "/home/jsnow/src/qemu/tests/qemu-iotests/iotests.py", line 365, in
qemu_io
return qemu_tool(*qemu_io_wrap_args(args),
File "/home/jsnow/src/qemu/tests/qemu-iotests/iotests.py", line 242, in
qemu_tool
raise VerboseProcessError(
qemu.utils.VerboseProcessError: Command
'('/home/jsnow/src/qemu/bin/git/tests/qemu-iotests/../../qemu-io',
'--cache', 'writeback', '--aio', 'threads', '-f', 'qcow2', '-c',
'read -P 4 3M 1M',
'/home/jsnow/src/qemu/bin/git/tests/qemu-iotests/scratch/3.img')'
returned non-zero exit status 1.
┏━ output ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
┃ qemu-io: can't open device
┃ /home/jsnow/src/qemu/bin/git/tests/qemu-iotests/scratch/3.img:
┃ Could not open backing file: Could not open backing file: Throttle
┃ group 'tg' does not exist
┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
It looks like we start with the img chain 3->2->1->0, then we commit 2
down into 1, but checking '3' fails somewhere in the backing
chain. Maybe a real bug?
Looks like my hunch was right: The problem is that it’s hard to figure
out a good backing file string when there are filters involved, and so
in one test here we generate one that contains a JSON description of the
backing subgraph including a throttle node. Outside of qemu, that
doesn’t make much sense, hence the error.
(And because we checked only for “pattern verification failed”
specifically, that error here never surfaced.)
I think (hope?) we can expect management tools to manually specify
backing file strings in such cases, like the attached diff does. That
seems to fix the problem.
Hanna
diff --git a/tests/qemu-iotests/040 b/tests/qemu-iotests/040
index c4a90937dc..30eb97829e 100755
--- a/tests/qemu-iotests/040
+++ b/tests/qemu-iotests/040
@@ -836,7 +836,8 @@ class TestCommitWithFilters(iotests.QMPTestCase):
job_id='commit',
device='top-filter',
top_node='cow-2',
- base_node='cow-1')
+ base_node='cow-1',
+ backing_file=self.img1)
self.assert_qmp(result, 'return', {})
self.wait_until_completed(drive='commit')
@@ -852,7 +853,8 @@ class TestCommitWithFilters(iotests.QMPTestCase):
job_id='commit',
device='top-filter',
top_node='cow-1',
- base_node='cow-0')
+ base_node='cow-0',
+ backing_file=self.img0)
self.assert_qmp(result, 'return', {})
self.wait_until_completed(drive='commit')
