James,
Right. I will take a look on Monday.
Thanks,
lin
James Cheng wrote:
> Hi Brian,
>
> With a DTrace as follows, I saw lots of free(0), unrelated to
> mlib_free(),
> when running /usr/bin/gnome-appearance-properties on vermillion_89.
>
> pid$target:libc:free:entry
> {
> printf("%s(0x%x)", probefunc, arg0);
> }
>
> I wonder if that's a concern to you guys.
>
> Thanks,
> -James
>
> On 05/09/08 07:58 PM, Brian Cameron wrote:
>>
>> Lin:
>>
>>> I'm curious why debug enabled libmetacity can't cause a crash and
>>> why crash doesn't happen on SPARC.
>>> Your fix may work well but it's not explanation of the reason to me.
>>
>> Leaving the height undefined will not have consistent behavior between
>> builds, since the undefined memory value could be different from build
>> to build, and between x86 and Sparc. So the behavior of this sort of
>> memory problem would be expected to vary.
>>
>> Using vermillion build 90, the undefined value was very large which
>> was causing a crash in replicate_rows in metacity/src/ui/theme.c
>> The call to gdk_pixbuf_new was returning NULL because the large
>> height value was causing it be unable to allocate memory. The
>> NULL value was passed into a function which failed due to an assert.
>>
>> I found that I could not get dbx to stop on the SEGV when I simply
>> ran "dbx /usr/bin/gnome-appearance-properties" and typed "run". Note
>> that the crash happened in the thumbnailer, which is run as a forked
>> subprocess. So I added a "sleep (15)" to the code, just after the
>> fork in gnome-control-center/capplets/common/theme-thumbnail.c in
>> the function theme_thumbnail_factory_init. Then I attached
>> the dbx debugger to the child process while it was sleeping.
>> After going through this hassle, the debugger was able to show
>> me the SEGV and it was a lot easier to track down the problem.
>>
>> Brian
>>
>>
>>> Brian Cameron wrote:
>>>>
>>>> I found that the appearance bug reappeared in vermillion-devel 90, and
>>>> disabling mediaLib had no affect on things. So my previous patch
>>>> to workaround the problem just hid the issue in vermillion-devel 89.
>>>>
>>>> Doing further research, it turns out that the problem was caused
>>>> by the metacity-08-trusted-extensions.diff file not setting
>>>> fgeom->height when TSOL isn't being used.
>>>>
>>>> Since the affected patch is huge, and the change is small, I'll just
>>>> explain my change rather than showing a diff file.
>>>>
>>>> I changed this hunk of the patch:
>>>>
>>>> ----
>>>>
>>>> @@ -621,8 +626,16 @@
>>>> fgeom->top_height + fgeom->bottom_height;
>>>>
>>>> fgeom->width = width;
>>>> +#ifdef BUILD_TX_CODE
>>>> +#ifdef HAVE_XTSOL
>>>> + if (tsol_is_available ())
>>>> + fgeom->height = height + fgeom->top_height; /*Trusted Frame
>>>> Layout Modifica
>>>> tion TFLM*/
>>>> + else
>>>> fgeom->height = height;
>>>> -
>>>> +#else
>>>> + fgeom->height = height;
>>>> +#endif
>>>> +#endif
>>>> fgeom->top_titlebar_edge = layout->title_border.top;
>>>> fgeom->bottom_titlebar_edge = layout->title_border.bottom;
>>>> fgeom->left_titlebar_edge = layout->left_titlebar_edge;
>>>>
>>>> ----
>>>>
>>>> Note that fgeom->height never gets set if BUILD_TX_CODE is not TRUE.
>>>>
>>>> So I changed it to the following code, which always sets fgeom->height
>>>> to height, and then resets it to the appropriate TSOL value if the
>>>> #defines and if-test pass. I think this code is a bit more simple
>>>> than dealing with so many embedded #else statements.
>>>>
>>>> ----
>>>>
>>>> @@ -622,7 +627,12 @@ meta_frame_layout_calc_geometry (const M
>>>>
>>>> fgeom->width = width;
>>>> fgeom->height = height;
>>>> -
>>>> +#ifdef BUILD_TX_CODE
>>>> +#ifdef HAVE_XTSOL
>>>> + if (tsol_is_available ())
>>>> + fgeom->height = height + fgeom->top_height; /*Trusted Frame
>>>> Layout Modifica
>>>> tion TFLM*/
>>>> +#endif
>>>> +#endif
>>>> fgeom->top_titlebar_edge = layout->title_border.top;
>>>> fgeom->bottom_titlebar_edge = layout->title_border.bottom;
>>>> fgeom->left_titlebar_edge = layout->left_titlebar_edge;
>>>>
>>>>
>>>>
>>>> ---
>>>>
>>>> Brian
>>>
>>
--
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