Re: [Xenomai-help] debug posix skin - pthread_cond_wait return EPERM

[Pierre.QUELIN@solystic.com]

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> Kolja Waschk wrote:
>>>> file cond-torture-posix
>>> Ok. On my side: I call set solib-absolute-prefix to where the debug
>>> binaries for the target filesystem are. And I call
>>> handle SIG34 nostop noprint pass.
>>>
>>> Coud you try and do the same?
>> Is SIG34 the same on blackfin? I do not remember ever having seen SIG34,
only
>> SIG32 ("Real-time event 32")
>>
>> Independent of that, the result is always the same SEGV. I cannot use
the absolute-prefix currently, as the directory layout is different on the
target. So my script is now
>>
>> set solib-absolute-prefix notexistent
>> set
solib-search-path /opt/uClinux/blackfin-linux-dist/staging/usr/lib:/opt/uClinux/bfin-linux-uclibc/bfin-linux-uclibc/runtime/lib

>> file cond-torture-posix
>> handle SIG34 nostop noprint pass
>> target remote 10.0.10.9:2222
>>
>> And regardless whether I add an "break main", the SEGV will occur
immediately after telling gdb to "cont".
>>
>> Does my "try.c" always succeed (all errbits=0x0010) in your environment?
>
> Ok, I get the failure if I set up a breakpoint right after the call to
> pthread_cond_wait, as noted by Pierre. After some debugging, it appears
> that the syscall is restarted whereas it should return to user-spacce
> and let the user-space skin do its job. So, it seems that somehow, the
> behaviour is different for gdb signals than for usual signals.
>
> Working on it now, will tell you when we have a status.

The following patch seems to fix the issue, but I am not yet sure
whether it is really correct:

diff --git a/ksrc/nucleus/shadow.c b/ksrc/nucleus/shadow.c
index d27494c..717a8a0 100644
--- a/ksrc/nucleus/shadow.c
+++ b/ksrc/nucleus/shadow.c
@@ -770,7 +770,7 @@ static inline void request_syscall_restart(xnthread_t
*thread,
                         if (__xn_interrupted_p(regs)) {
                                     __xn_error_return(regs,
                                                               (sysflags &
__xn_exec_norestart) ?
-
-ERESTARTNOHAND : -ERESTARTSYS);
+                                                              -EINTR :
-ERESTARTSYS);
                                     notify = !xnthread_test_state(thread,
XNDEBUG);
                         }



--
                                                                Gilles.

Sorry but I'm a novice.

As I understand, your patch is a kernel patch and I need to rebuild the
kernel package.
Where can I find the cond-torture-posix application to reproduce the
problem with your test case ?
My PC is a very standard one (Xeon dual core and my distro an Ubuntu 10.10
so I think it's very easy to reproduce the test case.
Do you know if there is a bug tracker where tickets are logged to be
informed when this point will be solved ?

Thank you for you help.

Pierre Quélin

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