Re: [tip:x86/urgent] x86, apic: Fix apic=debug boot crash

Yinghai Lu
2010-08-23T18:00:09Z

On 08/23/2010 07:54 AM, H. Peter Anvin wrote:
> It's already applied.
>
> "Daniel Kiper" <dkiper@net-space.pl> wrote:
>
>> Hi,
>>
>> On Fri, Aug 20, 2010 at 12:24:20PM -0700, Yinghai Lu wrote:
>>> On Fri, Aug 20, 2010 at 5:41 AM, tip-bot for Daniel Kiper
>>> <dkiper@net-space.pl> wrote:
>>>> Commit-ID: ?05e407603e527f9d808dd3866d3a17c2ce4dfcc5
>>>> Gitweb: ? ? http://git.kernel.org/tip/05e407603e527f9d808dd3866d3a17c2ce4dfcc5
>>>> Author: ? ? Daniel Kiper <dkiper@net-space.pl>
>>>> AuthorDate: Fri, 20 Aug 2010 00:46:16 +0200
>>>> Committer: ?Ingo Molnar <mingo@elte.hu>
>>>> CommitDate: Fri, 20 Aug 2010 10:18:28 +0200
>>>>
>>>> x86, apic: Fix apic=debug boot crash
>>>>
>>>> Fix a boot crash when apic=debug is used and the APIC is
>>>> not properly initialized.
>>>>
>>>> This issue appears during Xen Dom0 kernel boot but the
>>>> fix is generic and the crash could occur on real hardware
>>>> as well.
>>>
>>> Do you have any report on real hardware?
>>> that could not happen on real hardware.
>>
>> Till now no, however I think it is good idea
>> to apply this patch now. It is not worth to wait
>> for another null pointer dereference.

no, we should add BUG_ON() etc debug info there to see why that null cfg could happen.

because according to code, we should have null there.

Yinghai