site_archiver@lists.apple.com Delivered-To: Darwin-kernel@lists.apple.com From: "Herb Petschauer" <bogvardi@gmail.com> To: "Mark Stow" <markstow@hotmail.com> CC: Darwin-kernel@lists.apple.com Subject: Re: kextunload problem Date: Mon, 26 Jun 2006 09:18:45 -0700 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! _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.a... 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? On 26/06/06, Mark Stow <markstow@hotmail.com> wrote: 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 This email sent to site_archiver@lists.apple.com