On 07/23/2015 03:37 PM, Jan Kiszka wrote:
> On 2015-07-23 11:22, Philippe Gerum wrote:
>> On 07/23/2015 11:08 AM, Jan Kiszka wrote:
>>> On 2015-07-23 10:40, Philippe Gerum wrote:
>>>> On 07/21/2015 04:54 PM, Jan Kiszka wrote:
>>>>> On 2015-07-21 14:51, Philippe Gerum wrote:
>>>>>> On 07/21/2015 02:27 PM, Jan Kiszka wrote:
>>>>>>> Hi Philippe,
>>>>>>>
>>>>>>> just a heads up, I'll try to address this later:
>>>>>>>
>>>>>>> I received a report that include/rtdm/uapi/rtdm.h contains some data
>>>>>>> structures that are used between the kernel and the userspace library
>>>>>>> (so not directly by applications) and are not compatible with
>>>>>>> 32-on-64-bit (compat) scenarios. We should probably promote anything
>>>>>>> that is longer on 64-bit to that size, unconditionally. As this affects
>>>>>>> the ABI, it should be fixed before 3.0 release, ideally.
>>>>>>>
>>>>>>
>>>>>> That would require to fix up the client drivers (setsockopt, getsockopt
>>>>>> typically). Ok, I'll have a look when I'm done with testing the blackfin
>>>>>> port.
>>>>>
>>>>> Indeed. Just realized that there are already compat structs for the
>>>>> socket stuff. However, and that was what our user stumbled over, there
>>>>> is none for _rtdm_mmap_request. But that should be really internal, right?
>>>>>
>>>>
>>>> mmap() has the compat thunk for 32<->64 bit conversion already, so this
>>>> is ok.
>>>
>>> Ok... Rechecking the bug report here, the issue is rather the case that
>>> off_t becomes 64 bit when defining -D_FILE_OFFSET_BITS=64 for your
>>> userland. We are apparently required to account for that case as well.
>>>
>>
>> Ok, so let's move the offset member to loff_t and compat_loff_t in the
>> mmap request descriptors, that should do the trick.
>>
> 
> I only forwarded this suggestion internally, unfortunately cannot tell
> yet how it was implemented, just received the early feedback that it is
> not yet working. Maybe we are overseeing something, maybe something went
> wrong with the implementation. Will be checked tomorrow.
> 

This is likely an issue with the native alignment of those types, the
kernel may offset long members in the compat struct based on different
constraints than -m32 does.

-- 
Philippe.

_______________________________________________
Xenomai mailing list
[email protected]
http://xenomai.org/mailman/listinfo/xenomai

Reply via email to