Kevin Wolf <kw...@redhat.com> writes:
> Am 13.05.2014 um 19:44 hat Markus Armbruster geschrieben:
>> 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 "$@"
>> > wrote 512/512 bytes at offset 0
>> > 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
>> > incompatible_features 0x1
>> >
>> > Any idea what the difference is here?
>>
>> This is qemu-io aborting, as instructed. The command is
>>
>> qemu-io --cache writeback --cache writethrough -c 'write -P 0x5a
>> 0 512' -c abort scratch/t.qcow2
>>
>> [...]
>>
>> The additional "Aborted" line appears as soon as I put pass the qemu-io
>> command to a function that runs it using "$@". I don't need a subshell,
>> exec or anything:
>
> So that looks fine, I'd even consider it a feature to have the abort
> recorded explicitly. Let's just update the reference output. Another
> reason why qemu-iotests is bash-only, but we already have the same kind
> of output in other test cases, so this is not setting a precedence.
Okay, I'll respin it that way.
