linux-kernel - Re: PROBLEM: i915 causes complete desktop freezes in 4.15-rc5

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20180105220518.cmmof6rritm4bmjh@D-69-91-141-110.dhcp4.washington.edu>
Date:   Fri, 5 Jan 2018 17:05:18 -0500
From:   Alexandru Chirvasitu <achirvasub@...il.com>
To:     Chris Wilson <chris@...is-wilson.co.uk>
Cc:     Jani Nikula <jani.nikula@...ux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@...el.com>,
        intel-gfx@...ts.freedesktop.org,
        kernel list <linux-kernel@...r.kernel.org>
Subject: Re: PROBLEM: i915 causes complete desktop freezes in 4.15-rc5

Here we go.

I have

CONFIG_PAGE_POISONING not set
CONFIG_SLUB_STATS=y
CONFIG_SLUB_DEBUG not set
CONFIG_KASAN=y

.config attached along as well for verification, in case I missed
anything.

Again crashed by an attempt to open a terminal window.

---
Incidentally, Re: this:

> > > Ok, it looks like poisoning is only available if CONFIG_SLUB_DEBUG is
> > > set. Since it is not set, don't worry about it ;)

I actually still had PAGE_POISONING on after turning off SLUB_DEBUG,
so had to actively turn off both. And I never found a SLAB_POISON,
even after choosing SLAB over SLUB as an experiment.

That's an aside though; shouldn't matter much to the task at hand,
unless I misunderstood the instructions.

On Fri, Jan 05, 2018 at 08:02:48PM +0000, Chris Wilson wrote:
> Quoting Alexandru Chirvasitu (2018-01-05 19:58:42)
> > OK, I then plan to try with the previous config, plus these
> > modifications:
> > 
> > CONFIG_PAGE_POISONING not set
> > CONFIG_SLUB_STATS=y
> > 
> > I'm a little puzzled about this:
> 
> [snip]
> 
> > > It would be CONFIG_SLUB_STATS and then you would a
> > > /sys/kernel/slab/i915_dependency/ directory with all the details of the
> > > slab, and in particular a poison file showing the status (and allowing
> > > it to modified) of slab poisoning
> > > 
> > > Ok, it looks like poisoning is only available if CONFIG_SLUB_DEBUG is
> > > set. Since it is not set, don't worry about it ;)
> > 
> > I actually do have SLUB_DEBUG set to 'y' in the kernel whose dmesg I
> > last sent you.
> 
> Ah, ok. I was looking at the config attached the first mail. Turn off
> SLUB_DEBUG for now to give ourselves the best chance at getting
> something from kasan. I hope it's worth the effort...
> -Chris

View attachment "log-void-no-psn" of type "text/plain" (66821 bytes)

View attachment "void-cfg-no-psn" of type "text/plain" (197192 bytes)