On Mon, Apr 9, 2012 at 3:09 PM, Dmitry Stogov <dmi...@zend.com> wrote:
> Hi Laruence,
>
> I think your patch is right, but I've never seen this problem before.
> Is it related to your own extension? What does it do? Why we didn't see this
> problem with other extensions?
a persistent configure extension, it loads all ini configure file at MINIT.
>
> Finally, I think that such persistent HashTables must be very rare, so
> introducing additional check would slowdown the engine. So allocating
> zend_gc_info may be a better solution.
okey, it's really rare usages :)
thanks
>
> Thanks. Dmitry.
>
>
> On 04/06/2012 04:32 PM, Laruence wrote:
>>
>> Hi:
>> and, yes, extension can change their code to alloc a zend_gc_info
>> size(what I do now).
>>
>> however, I think, it's no need for zend_gc care about persistent
>> memorys, right?
>>
>> thanks
>>
>>
>> On Fri, Apr 6, 2012 at 8:21 PM, Laruence<larue...@php.net> wrote:
>>>
>>> Hi Dmitry:
>>>
>>> zend gc was introducted in 5.3
>>>
>>> thinking of a zval which is a Hashtable allocated by a extension in
>>> persistent,
>>> and it also has hashtable children in it,
>>>
>>> then , if the extension return this to php script:
>>>
>>> array_init(return_value);
>>> zend_hash_copy(Z_ARRVAL_P(return_value),
>>> Z_ARRVAL_P(persitent_zval_hashtable),
>>> ***)..
>>>
>>> since zval_copy_ctor does shallow copy, so the persistent array return to
>>> the
>>> php
>>> script.
>>>
>>>
>>> then if it happen to be parsed by zval_ptr_dtor, then the persistent
>>> array will
>>> be
>>> parsed by gc_zval_possible_root,
>>>
>>> ZEND_API void gc_zval_possible_root(zval *zv TSRMLS_DC)
>>> {
>>>
>>> ..................
>>>
>>> if (GC_ZVAL_GET_COLOR(zv) != GC_PURPLE) {
>>> GC_ZVAL_SET_PURPLE(zv);
>>> ..................
>>>
>>> then the malloc info of the block(not sure before or after) will be
>>> polluted.
>>>
>>> then when the extension try to free the block, a warning will be show
>>> like:
>>>
>>> munmap_chunk(): invalid pointer 0x*******
>>>
>>>
>>> I have make a patch for this(https://bugs.php.net/bug.php?id=61649),
>>> if you think it's okey, I will commit it to all branches,
>>>
>>> thanks
>>>
>>> --
>>> Laruence Xinchen Hui
>>> http://www.laruence.com/
>>
>>
>>
>>
>
--
Laruence Xinchen Hui
http://www.laruence.com/
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