Re: Problem registering interrupt

["Sébastien Taylor" <sebastient@otii.com>]

So the crash is happening because the handler pointer is null in the 
irq_desc for interrupt 49.  Is there something that I was supposed to 
do to setup that handler before registering my interrupt?  This was 
working fine under 2.4, is it a change in 2.6 or just in the alchemy 
port specifically?

Thanks for the help and happy new years,
Sébastien


Le 04-12-22, à 03:44, Jan-Benedict Glaw a écrit :

> On Wed, 2004-12-22 11:19:06 +0100, moreau francis 
> <francis_moreau2000@yahoo.fr>
> wrote in message 
> <20041222101906.27137.qmail@web25109.mail.ukl.yahoo.com>:
>>
>>> CPU 0 Unable to handle kernel paging request at
>>> virtual address 00000004, epc =4
>>
>> Well it suggests me that your driver is trying to
>> access a really nasty pointer: 0x00000004...
>> How did you get this address ? From user space ?
>
> Accesses to nearly NULL are normally structure accesses where a pointer
> to a given struct was supplied as a NULL pointer.
>
> So an access to 0x00000004 is most probably an access to the second
> element of a struct, given/expected that all fields are usually 4-byte
> aligned.
>
>> From looking at ./kernel/irq/manage.c:setup_irq(), I guess that you
> supply NULL as the "struct irqaction *", which is the 2nd argument of
> setup_irq(). It's 2nd structure element is "flags" then... This is the
> first thing accessed by the "new" pointer in setup_irq().
>
> MfG, JBG
>
> -- 
> Jan-Benedict Glaw       jbglaw@lug-owl.de    . +49-172-7608481         
>     _ O _
> "Eine Freie Meinung in  einem Freien Kopf    | Gegen Zensur | Gegen 
> Krieg  _ _ O
>  fuer einen Freien Staat voll Freier Bürger" | im Internet! |   im 
> Irak!   O O O
> ret = do_actions((curr | FREE_SPEECH) & ~(NEW_COPYRIGHT_LAW | DRM | 
> TCPA));