Re: [PATCH] x86/pat: Fix off-by-one bugs in interval tree search

From: Davidlohr Bueso
Date: Sun Dec 01 2019 - 12:05:59 EST


On Sun, 01 Dec 2019, Ingo Molnar wrote:
So the correct parameter to use in the interval tree searches is not
'end' but 'end-1'.

Yes absolutely, I overlooked this in the final conversion. Going through some
older conversions, I had this end-1 at one point. Lookups need half-open intervals,
consistent with what memtype_interval_end() does.

[...]

Patch is only lightly tested, so take care. (Patch is emphatically not
signed off yet, because I spent most of the day on this and I don't yet
trust my fix - all of the affected sites need to be reviewed more
carefully.)

As a general note, this is rather consistent with how all interval-tree
users that need [a,b) nodes use the api.

Thanks,
Davidlohr