From mboxrd@z Thu Jan  1 00:00:00 1970
Subject: Re: RTDM module ownership
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From: Jan Kiszka <jan.kiszka@siemens.com>
Message-ID: <50c505c0-39bc-26c0-6188-1e2a2fe41536@siemens.com>
Date: Fri, 3 Jul 2020 11:10:41 +0200
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To: Richard Weinberger <richard@nod.at>
Cc: Richard Weinberger <richard.weinberger@gmail.com>, xenomai <xenomai@xenomai.org>

On 03.07.20 08:22, Richard Weinberger wrote:
> ----- Ursprüngliche Mail -----
>>> In contrast, on regular Linux rmmod will refuse to unload the module
>>> if the device node is still open because fops_get() or other helpers
>>> gained a reference on the owner.
>>>
>>
>> First of all, your driver is apparently not reacting on the close
>> request that it receives in that case. This leads the the stall you see.
> 
> Huh? rmmmod triggers close of what?
> *confused*
>   

rmmod -> module cleanup -> rtdm_dev_unregister -> rtdm_device_flush_fds

>> Still, we could indeed run some module_put/get on open/socket/close. I
>> thought we did, but that was once RTnet [1].
> 
> Yes. Would be nice. :-)
> 

Just like a patch would be...

Jan

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