Re: kextunload problem
Re: kextunload problem
- Subject: Re: kextunload problem
- From: "Herb Petschauer" <email@hidden>
- Date: Tue, 27 Jun 2006 08:32:30 -0700
Hard to say, at this point it will be something silly though :-)
It really depends on what it is you are actually implementing...
Good luck!
-H.
On 27/06/06,
Mark Stow <email@hidden> wrote:
thanks again - sorry - I've not posted anything before!
my free() calls super::free(). In an effort to find out why it's not
unloading, all the life cycle functions just call super (and IOLog for some
diags).
any ideas why logging out and back in again would cure this kextunload fail
issue?
>From: "Herb Petschauer" <email@hidden>
>To: "Mark Stow" <
email@hidden>
>CC: email@hidden
>Subject: Re: kextunload problem
>Date: Tue, 27 Jun 2006 07:37:40 -0700
>
>Ok, top posting it is... :-)
>
>Look at the OSObject.cpp code, I think the retain count is set to "1" in
>the
>constructor, so I would expect the release() calls to go one beyond the
>retain() calls.
>
>A simple solution, does your free() method call super::free()? That's my
>mistake 9 times of out 10.
>
>See also this thread: <
>
http://lists.apple.com/archives/darwin-drivers/2006/May/msg00091.html>
>
>hth,
>-H.
>
>On 27/06/06, Mark Stow <email@hidden> wrote:
>>
>>Herb, thanks. I have some more info -
>>The system log tells me there is one instance of my class which is why it
>>can't unload. It doesn't make any difference if the firewire device is
>>plugged in or not.
>>
>>I tried overriding retain() and release(), and in both cases when
>>kextunload
>>fails or succeeds, release() seems to be called once more than retain().
>>
>>I also noticed that if I delete the driver from system/library/extensions
>>and reboot, so it's not loaded on boot, and then copy it back and kextload
>>
>>it, kextunload will succeed.
>>
>>If someone is over-retaining (and it seems to need to happen on bootup)
>>wouldn't I see a difference in the retain() release() counts when unload
>>fails?
>>
>>
>> >From: "Herb Petschauer" < email@hidden>
>> >To: "Mark Stow" <email@hidden
>
>> >CC: email@hidden
>> >Subject: Re: kextunload problem
>> >Date: Mon, 26 Jun 2006 09:18:45 -0700
>> >
>> >On 26/06/06, Mark Stow <email@hidden > wrote:
>> >>
>> >>Hi - I'm having some difficulties with kextunload.
>> >>I am working on a firewire device driver which derives from IOService.
>> >>The
>> >>problem seems to be that free() never gets called. However, if I log
>>out,
>> >>then log back in again, everything works fine - ie free() is called,
>>and
>> >>the
>> >>driver unloads correctly.
>> >>I have stripped the code down to a bare minimum of just the life cycle
>> >>functions, which in turn just call into IOService. I see init(),
>>attach()
>> >>and start() being called, and then on unload stop() detach() but not
>> >>free().
>> >> Any help/ideas would be appreciated!
>> >>
>> >>
>> >>
>> >
>> >Check your system.log, there's probably a message telling you why your
>>kext
>> >won't unload (e.g. Couldn't unload kext (name) because there are x
>> >instances
>> >of <some class>). free() doesn't get called until the last release()
>> >(retain/release must balance) so I suspect someone is
>>over-retaining(). Is
>> >your Firewire drive unplugged when you try and unload the kext? The
>> >/dev/disk nodes are usually left created until you unplug the
>>device. Just
>> >a thought...
>> >
>> >-H.
>>
>>_________________________________________________________________
>>Windows Live™ Messenger has arrived. Click here to download it for free!
>>
http://imagine-msn.com/messenger/launch80/?locale=en-gb
>>
>>
_________________________________________________________________
The new MSN Search Toolbar now includes Desktop search!
http://join.msn.com/toolbar/overview
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Darwin-kernel mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden