Re: [PATCH 00 of 11] x86: separate pmd lifetime from pgd

[Jeremy Fitzhardinge <jeremy@goop.org>]

Ingo Molnar wrote:
> and after a session of bisection, the winner patch is:
>
>   Subject: x86: unify PAE/non-PAE pgd_ctor
>
> which is a tad unexpected, given the relatively harmless nature of the 
> patch. (but then again, nothing is really harmless in PAE land.)
>   

Oh, well, good.  At least off-the-cuff diagnosis was right.  I must have 
overlooked some detail in that merge.

> btw., this is not fair i think: your patch was apparently caught by the 
> new debugging helper that tells about itself here:
>
>   
>> [   29.389872] debug: unmapping init memory c0b03000..c0b6f000
>>     
>
> note the close proximity of c0b6f000 and ebx = c0b6fc08. [ I regularly 
> come up with such nasty tricks and debugging helpers like that to catch 
> bad patches off-guard. You have been warned! ;-) ]
>   

Hm, perhaps, but it could be as easily coincidence.  The place there 
initmem is freed is close to where it first needs to rely on a 
non-initmm pagetable.  I presume that message means that c0b6f000 was 
*not* freed.

    J