Re: [Qemu-devel] [Qemu-block] [PATCH v5 4/6] iotests: Valgrind fails with nonexistent directory

[Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>]

On 16/08/2019 03:55, John Snow wrote:
> 
> 
> On 7/19/19 12:30 PM, Andrey Shinkevich wrote:
>> The Valgrind uses the exported variable TMPDIR and fails if the
>> directory does not exist. Let us exclude such a test case from
>> being run under the Valgrind and notify the user of it.
>>
>> Suggested-by: Kevin Wolf <kwolf@redhat.com>
>> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
>> ---
>>   tests/qemu-iotests/051 | 4 ++++
>>   1 file changed, 4 insertions(+)
>>
>> diff --git a/tests/qemu-iotests/051 b/tests/qemu-iotests/051
>> index ce942a5..f8141ca 100755
>> --- a/tests/qemu-iotests/051
>> +++ b/tests/qemu-iotests/051
>> @@ -377,6 +377,10 @@ printf %b "qemu-io $device_id \"write -P 0x33 0 4k\"\ncommit $device_id\n" |
>>   $QEMU_IO -c "read -P 0x33 0 4k" "$TEST_IMG" | _filter_qemu_io
>>   
>>   # Using snapshot=on with a non-existent TMPDIR
>> +if [ "${VALGRIND_QEMU}" == "y" ]; then
>> +    _casenotrun "Valgrind needs a valid TMPDIR for itself"
>> +fi
>> +VALGRIND_QEMU="" \
>>   TMPDIR=/nonexistent run_qemu -drive driver=null-co,snapshot=on
>>   
>>   # Using snapshot=on together with read-only=on
>>
> 
> The only other way around this would be a complicated mechanism to set
> the TMPDIR for valgrind's sub-processes only, with e.g.
> 
> valgrind ... env TMPDIR=/nonexistent qemu ...
> 
> ... It's probably not worth trying to concoct such a thing; but I
> suppose it is possible. You'd have to set up a generic layer for setting
> environment variables, then in the qemu shim, you could either set them
> directly (non-valgrind invocation) or set them as part of the valgrind
> command-line.
> 
> Or you could just take my R-B:
> 
> Reviewed-by: John Snow <jsnow@redhat.com>
> 

Thanks again John for your review and the advice.
Probably, it doesn't worth efforts to manage that case because QEMU 
should fail anyway with the error message "Could not get temporary 
filename: No such file or directory". So, we would not benefit much from 
that run. We have other test cases that cover the main functionality. 
It's just to check the QEMU error path for possible memory issues. Shall we?

Andrey
-- 
With the best regards,
Andrey Shinkevich