[Intel-gfx] [PATCH 1/2] mm: Track actual nr_scanned during shrink_slab()

[Andrew Morton]

On Thu, 24 Aug 2017 10:00:49 +0200 Vlastimil Babka <vbabka at suse.cz> wrote:

> > Even if a
> > shrinker has a mistake, VM will have big trouble like infinite loop.
> 
> We could fake 0 as 1 or something, at least.

If the shrinker returns sc->nr_scanned==0 then that's a buggy shrinker
- it should return SHRINK_STOP in that case.  Only a single shrinker
(i915) presently uses sc->nr_scanned and that one gets it right.  I
think it's OK - there's a limit to how far we should go defending
against buggy kernel code, surely.