Re: [PATCH v5 07/27] mm/mmap: Create a guard area between VMAs

[Florian Weimer]

* Dave Hansen:

> On 10/11/2018 08:15 AM, Yu-cheng Yu wrote:
>> Create a guard area between VMAs to detect memory corruption.
>
> This is a pretty major change that has a bunch of end-user implications.
>  It's not dependent on any debugging options and can't be turned on/off
> by individual apps, at runtime, or even at boot.
>
> Its connection to this series is also tenuous and not spelled out in the
> exceptionally terse changelog.

I agree.  We did have application failures due to the introduction of
the stack gap, so this change is likely to cause failures when applied
to existing mappings as well.