Re: PCI: fix an oops in some pci devices on hotplug remove when their resources are being freed.

Matthew Wilcox
2005-04-02T03:53:34Z

On Fri, Apr 01, 2005 at 07:31:41PM -0800, Greg KH wrote:
> I agree. However, SGI seems to have some majorly <insert expletive here>
> hardware and drivers that cause this line to release a already released
> resource. See the other part of this patch for the part where this
> resource is supposedly freed up.

That one's even more stupid:

+++ b/kernel/resource.c 2005-04-01 15:37:58 -08:00
@@ -505,6 +505,7 @@
*p = res->sibling;
write_unlock(&resource_lock);
kfree(res);
+ res = NULL;
return;
}
p = &res->sibling;

This pointer is a local variable! Setting it to null right before return
cannot possibly affect anything.

> I took the patch as it doesn't hurt anyone, and it gets them off of my
> back. But if you so much as think this patch isn't needed, I'll gladly
> revert it, as I'm really not trusting any PCI hotplug patches coming out
> from them anymore...

I think the problem is that they have a majorly hacked tree they're
working from as well as some quite inexperienced people working on it.
They need to do more internal peer review ... and clearly I need to
start reviewing their patches more carefully.

So yes, please revert this patch. There is no way it can possibly
affect anything.

--
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