Re: [PATCH v4 00/17] khwasan: kernel hardware assisted address sanitizer

From: Andrew Morton
Date: Wed Jun 27 2018 - 21:11:47 EST


On Wed, 27 Jun 2018 17:59:00 -0700 Vishwath Mohan <vishwath@xxxxxxxxxx> wrote:

> > > > time consume much less memory, trading that off for somewhat imprecise
> > > > bug detection and being supported only for arm64.
> > >
> > > Why do we consider this to be a worthwhile change?
> > >
> > > Is KASAN's memory consumption actually a significant problem? Some
> > > data regarding that would be very useful.
> >
> > On mobile, ASAN's and KASAN's memory usage is a significant problem.
> > Not sure if I can find scientific evidence of that.
> > CC-ing Vishwath Mohan who deals with KASAN on Android to provide
> > anecdotal evidence.
> >
> Yeah, I can confirm that it's an issue. Like Kostya mentioned, I don't have
> data on-hand, but anecdotally both ASAN and KASAN have proven problematic
> to enable for environments that don't tolerate the increased memory
> pressure well. This includes,
> (a) Low-memory form factors - Wear, TV, Things, lower-tier phones like Go
> (c) Connected components like Pixel's visual core
> <https://www.blog.google/products/pixel/pixel-visual-core-image-processing-and-machine-learning-pixel-2/>
>
>
> These are both places I'd love to have a low(er) memory footprint option at
> my disposal.

Thanks.

It really is important that such information be captured in the
changelogs. In as much detail as can be mustered.