On 2015-02-16 20:35, Philippe Gerum wrote:
> On 02/16/2015 08:11 PM, Jan Kiszka wrote:
>> On 2015-02-16 19:52, Jan Kiszka wrote:
>>> On 2015-02-16 18:52, Jan Kiszka wrote:
>>>> On 2015-02-16 18:48, Philippe Gerum wrote:
>>>>> On 02/16/2015 06:35 PM, Jan Kiszka wrote:
>>>>>> The following changes since commit 
>>>>>> 00d8a6f2e95453f61ae97b6587dba03bc91c7e1a:
>>>>>>
>>>>>>   arm/ipipe: Resolve trival merge conflicts (2015-01-14 17:00:22 +0100)
>>>>>>
>>>>>> are available in the git repository at:
>>>>>>
>>>>>>   git://git.xenomai.org/ipipe-jki 
>>>>>>
>>>>>> for you to fetch changes up to f982e48ce99e1bc9e71eac21830adac2db265c98:
>>>>>>
>>>>>>   x86/ipipe: Restore invocation of ipipe_unlock_irq from 
>>>>>> startup_ioapic_irq (2015-02-16 18:22:21 +0100)
>>>>>>
>>>>>> All patches apply to 3.16 as well but weren't tested there yet. Still
>>>>>> analyzing strange
>>>>>>
>>>>>> traps: (systemd)[1420] trap invalid opcode ip:7f4d138f612b 
>>>>>> sp:7fff4fd8f568 error:0 in libpthread-2.19.so[7f4d138e5000+18000]
>>>>>>
>>>>>> on the target under 3.14...
>>>>>>
>>>>>
>>>>> Register trashing on the fast call path (system_call_after_gs) maybe.
>>>>> Forcing CONFIG_IPIPE_LEGACY there might help ruling this out.
>>>>
>>>> That's without any Xenomai configured. But I will check.
>>>
>>> This is where it traps in libpthread:
>>>
>>>    1112b:       c7 f8 00 00 00 00       xbeginq 11131 
>>> <__lll_lock_elision+0x51>
>>>
>>> For some reason, glibc starts to believe it could use RTM on that
>>> machine - although this is clearly not available (Haswell i7, thus a
>>> buggy CPU). Need to understand which feature check goes wrong, and why
>>> only on I-pipe enabled kernels.
>>>
>>> The good news is that I still have a similar and unresolved report from
>>> early customer tests. That could solve their issues as well (they
>>> caused massive domain migrations).
>>
>> Wait - we were already one step further: a potential trigger for this
>> behaviour is a nullified pthread mutex. The decision to take the TSX
>> path is based on field in that struct, and 0 means transactional. Guess
>> I need a better reproduction case than some systemd service.
> 
> Which glibc release are you running?

2.19.

Jan

-- 
Siemens AG, Corporate Technology, CT RTC ITP SES-DE
Corporate Competence Center Embedded Linux

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

Reply via email to