From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Fri, 12 Feb 2010 16:37:29 +0100
From: Jan Kiszka <jan.kiszka@domain.hid>
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Subject: Re: [Xenomai-core] Yet another ((weak)) bug
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: xenomai-core <xenomai@xenomai.org>

Gilles Chanteperdrix wrote:
> Jan Kiszka wrote:
>> Hi Gilles,
>>
>> this one requires some fixing too:
>>
>> xeno_sem_heap is marked weak. xeno_init_sem_heaps is called once per
>> initialized skin. It unmaps any existing heap and creates a new one.
>> That's already fragile during constructor run, but it's lethal during
>> process runtime, ie. when using dlopen.
>>
>> I think the solution is to handle forks separately and only remap in
>> that case. Digging in this direction now.
>>
>> BTW, what triggers the re-run of xeno_init_sem_heaps after a fork so far?
> 
> It must be done for the child process to get a private heap different
> from the parent process. I would guess it is handled by pthread_atfork.

Ah, only the POSIX skin does that. However, sem-heaps must not be
POSIX-only. OK, patch in the make.

Jan

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