[PATCHv4][PING][BZ #17833] _dl_close_worker() does not release inconsistent objects.

[Yury Gribov]

On 05/27/2015 04:04 PM, H.J. Lu wrote:
> On Wed, May 27, 2015 at 5:17 AM, Pavel Kopyl <p.kopyl@samsung.com> wrote:
>>
>>
>> On 05/13/2015 02:40 PM, Pavel Kopyl wrote:
>>>
>>>
>>>
>>> On 04/24/2015 02:47 PM, H.J. Lu wrote:
>>>>
>>>> On Fri, Apr 24, 2015 at 3:33 AM, Pavel Kopyl <p.kopyl@samsung.com> wrote:
>>>>>
>>>>>
>>>>> On 03/03/2015 12:13 PM, Pavel Kopyl wrote:
>>>>>>
>>>>>>
>>>>>> On 03/01/2015 10:17 PM, Mike Frysinger wrote:
>>>>>>>
>>>>>>> On 27 Feb 2015 16:32, Pavel Kopyl wrote:
>>>>>>>>
>>>>>>>> --- /dev/null
>>>>>>>> +++ b/elf/tst-unique5lib.cc
>>>>>>>> @@ -0,0 +1,13 @@
>>>>>>>> +
>>>>>>>
>>>>>>> i know existing tests are bad examples, but lets try and start fixing
>>>>>>> that.
>>>>>>> namely, there should be a header here giving a quick overview of what
>>>>>>> it
>>>>>>> is
>>>>>>> exactly you're testing for, and a BZ reference.
>>>>>>>
>>>>>>>> +extern int not_exist ();
>>>>>>>> +
>>>>>>>> +inline int make_unique ()
>>>>>>>> +{
>>>>>>>> +  static int unique;
>>>>>>>> +  return ++unique;
>>>>>>>> +}
>>>>>>>> +
>>>>>>>> +int foo ()
>>>>>>>> +{
>>>>>>>> +  return make_unique () + not_exist ();
>>>>>>>> +}
>>>>>>>
>>>>>>> i don't know if this is just copy & pasting, but prototypes that do
>>>>>>> not
>>>>>>> intend
>>>>>>> to take args should always be (void).
>>>>>>> -mike
>>>>>>
>>>>>>
>>>>>> Thanks for review, I fixed that in patch v3.
>>>>>
>>>>> Ping.
>>>>>
>>>> Some comments:
>>>>
>>>> 1. The bug report is against STB_GNU_UNIQUE.  But I don't see
>>>> STB_GNU_UNIQUE in
>>>> testcase.  I can't tell if the original STB_GNU_UNIQUE bug is fixed.
>>>> 2. Your testcase ignores dlopen error.  Why should it work at all?
>>>> 3. Your testcase doesn't use test-skeleton.c.
>>>>
>>>
>>> Thanks for review!
>>>
>>> 1. I added some comments in testcase to be more clear.
>>>
>>> 2. Actually the call below is expected to return NULL because of undefined
>>> symbol in the library.
>>>
>>> dlopen ("$ORIGIN/tst-unique5lib.so", RTLD_NOW);
>>>
>>> It's a goal of this testcase: I need some library with STB_GNU_UNIQUE
>>> symbols that returns error when trying to load it.
>>> In new patch version I especially point out to this fact by checking
>>> return value.
>>>
>>> 3. It seems for me that template of the test-skeleton.c is not appropriate
>>> because this testcase has two related binary - library and executable.
>>>
>>>
>>> -Pavel
>>
>> Ping.
>>
>
> Since you changed DF_1_NODELETE, how did you test it?  Does your test
> fail without the DF_1_NODELETE change?

AFAIU DF_1_NODELETE change is necessary. Otherwise unique symbols force 
library to remain loaded in half-initialized state (with missing 
dependencies). This usecase is demonstrated by the testcase in patch.

-Y