Re: kern/51393: Reproducible KASSERT in UVM

[Maxime Villard <max%m00nbsd.net@localhost>]

Le 06/08/2016 à 20:00, Martin Husemann a écrit :
> The following reply was made to PR kern/51393; it has been noted by GNATS.
>
> From: Martin Husemann <martin%duskware.de@localhost>
> To: gnats-bugs%NetBSD.org@localhost
> Cc:
> Subject: Re: kern/51393: Reproducible KASSERT in UVM
> Date: Sat, 6 Aug 2016 19:57:48 +0200
>
>  Same as kern/51254?

Apparently, yes.

>  I am tempted to call it a compiler issue.

That seems highly unlikely to me. There must be another unrelated issue in
UVMHIST, or whatever.

The real bug might be hiding in the way hints work. The code I posted in this
report generates orig_hint=0, so obviously there is no way for 'hint' to be
below zero, and the allocation should theoretically fail.

This 'theoretically' is necessarily wrong, since most of the vm space could be
available - meaning the allocation should succeed.