Re: [PATCH -tip/master] x86: io-apic - interrupt remapping fix

[Suresh Siddha <suresh.b.siddha@intel.com>]

On Mon, Sep 22, 2008 at 09:56:37PM -0700, Cyrill Gorcunov wrote:
> [Suresh Siddha - Mon, Sep 22, 2008 at 06:16:21PM -0700]
> | On Mon, Sep 22, 2008 at 05:57:38PM -0700, Siddha, Suresh B wrote:
> | > On Fri, Sep 19, 2008 at 05:33:20AM -0700, Cyrill Gorcunov wrote:
> | > > Interrupt remapping could lead to NULL dereference in case of
> | > > kzalloc failed and memory leak in other way. So fix the
> | > > both cases.
> | > >
> | > > Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
> | > > ---
> | > >
> | > > Ingo, the patch is on top of applied one.
> | > >
> | > > If I remember correctly Suresh was involved in
> | > > this - so I think he could take a look and review
> | > > the patch (please).
> | > >
> | >
> | > Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
> |
> | oops. Cyrill some typo here:
> |
> | +       for (; apic > 0; apic--)
> | +               kfree(early_ioapic_entries[apic]);
> | +       kfree(early_ioapic_entries[apic]);
> |
> 
> Hi Suresh, thanks for review!
> 
> Well it's not typo actually :) Of course it could
> be like
> 
>         for (--apic; apic > 0; apic--)
> or
>         for (apic--; apic > 0; apic--)
> 
> but it will be a rpoblem in case if apic = 0 and
> if someday apic would be unsigned int. So I prefered
> to have _one_ kfree(NULL) call instead :)
> 
> I hope i didn't miss anything.

This is too confusing. Please change it to something simple, like:

	for (i = 0; i < apic; i++)
		kfree(early_ioapic_entries[i]);

or

	for (apic = 0; apic < nr_ioapics; apic++)
		kfree(early_ioapic_entries[apic]);

thanks,
suresh