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Date:   Wed, 11 Sep 2019 15:51:00 +0200
From:   Michal Hocko <mhocko@kernel.org>
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On Wed 11-09-19 15:20:02, Michal Hocko wrote:
[...]
> > 4. Continuously report, not the "one time report everything" approach.
> 
> So you mean the allocator reporting this rather than an external code to
> poll right? I do not know, how much this is nice to have than must have?

Another idea that I haven't really thought through so it might turned
out to be completely bogus but let's try anyway. Your "report everything"
just made me look and realize that free_pages_prepare already performs
stuff that actually does something similar yet unrelated.

We do report to special page poisoning, zeroying or
CONFIG_DEBUG_PAGEALLOC to unmap the address from the kernel address
space. This sounds like something fitting your model no?
-- 
Michal Hocko
SUSE Labs