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Date: Thu, 15 Jan 2009 13:09:02 +0100
From: Philippe Gerum <rpm@xenomai.org>
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Subject: Re: [Xenomai-core] Pending patches
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To: Jan Kiszka <jan.kiszka@domain.hid>
Cc: xenomai-core <xenomai@xenomai.org>

Jan Kiszka wrote:
> Philippe Gerum wrote:
>> Jan Kiszka wrote:
>>> commit 728fc8970e2032b3280971788f1223f3ad82d80d
>>> Author: Jan Kiszka <jan.kiszka@domain.hid>
>>> Date:   Thu Jan 15 11:10:24 2009 +0100
>>>
>>>     xnpipe: Fix racy callback handlers
>>>     
>>>     Invocation of input, output and alloc handler must take place under
>>>     nklock to properly synchronize with xnpipe_disconnect. Change all
>>>     callers to comply with this policy.
>>>
>> That one is under investigation. I agree on the bug report (thanks btw), but I
>> disagree on the fix. Basically, we can't run all hooks under nklock. For
>> instance, the alloc_handler may issue kmalloc() calls when issued from the Linux
>> write endpoint.
> 
> You mean it /could/? Because no in-tree user (ie. native) calls
> rt-unsafe services from its alloc_handler.
>

When you export a public interface, it is better not to make it incompatible
unless there is no other way to fix a situation. Doing so is last resort for me.

> Jan
> 


-- 
Philippe.