Fam Zheng <f...@redhat.com> writes:
> On Tue, 05/13 10:46, Markus Armbruster wrote:
>> The shell script attempts to suppress core dumps like this:
>>
>> old_ulimit=$(ulimit -c)
>> ulimit -c 0
>> $QEMU_IO arg...
>> ulimit -c "$old_ulimit"
>>
>> This breaks the test hard unless the limit was zero to begin with!
>> ulimit sets both hard and soft limit by default, and (re-)raising the
>> hard limit requires privileges. Broken since it was added in commit
>> dc68afe.
>>
>> Could be fixed by adding -S to set only the soft limit, but I'm not
>> sure how portable that is in practice. Simply do it in a subshell
>> instead, like this:
>>
>> (ulimit -c 0; exec $QEMU_IO arg...)
>>
>> Signed-off-by: Markus Armbruster <arm...@redhat.com>
>> ---
>> tests/qemu-iotests/039 | 18 ++++++------------
>> 1 file changed, 6 insertions(+), 12 deletions(-)
>>
>> diff --git a/tests/qemu-iotests/039 b/tests/qemu-iotests/039
>> index b9cbe99..182b0f0 100755
>> --- a/tests/qemu-iotests/039
>> +++ b/tests/qemu-iotests/039
>> @@ -67,10 +67,8 @@ echo "== Creating a dirty image file =="
>> IMGOPTS="compat=1.1,lazy_refcounts=on"
>> _make_test_img $size
>>
>> -old_ulimit=$(ulimit -c)
>> -ulimit -c 0 # do not produce a core dump on abort(3)
>> -$QEMU_IO -c "write -P 0x5a 0 512" -c "abort" "$TEST_IMG" | _filter_qemu_io
>> -ulimit -c "$old_ulimit"
>> +(ulimit -c 0 # do not produce a core dump on abort(3)
>> +exec $QEMU_IO -c "write -P 0x5a 0 512" -c "abort" "$TEST_IMG") |
>> _filter_qemu_io
>
> This works well.
>
> But when I try to put this in a function to avoid repeating:
>
> function _no_dump_exec()
> {
> (ulimit -c 0; exec "$@")
> }
>
> _no_dump_exec $QEMU_IO -c "write -P 0x5a 0 512" -c "abort" "$TEST_IMG") |
> _filter_qemu_io
>
> it doesn't work:
>
> 039 1s ... - output mismatch (see 039.out.bad)
> --- 039.out 2014-05-13 12:10:39.248866480 +0800
> +++ 039.out.bad 2014-05-13 17:19:46.161986618 +0800
> @@ -9,6 +9,7 @@
>
> == Creating a dirty image file ==
> Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
> +./039: line 51: 10517 Aborted "$@"
> wrote 512/512 bytes at offset 0
> 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> incompatible_features 0x1
>
> Any idea what the difference is here?
Full patch of your version, please.
