linux-kernel - Re: Critical regression in 4.7-rcX

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

Message-ID: <9d76da4f-6b5b-9bfc-e3c5-475422696a5f@lwfinger.net>
Date:	Fri, 15 Jul 2016 10:34:21 -0500
From:	Larry Finger <Larry.Finger@...inger.net>
To:	Ville Syrjälä <ville.syrjala@...ux.intel.com>,
	Daniel Vetter <daniel.vetter@...ll.ch>
Cc:	Linus Torvalds <torvalds@...ux-foundation.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Shubhangi Shrivastava <shubhangi.shrivastava@...el.com>,
	Jani Nikula <jani.nikula@...ux.intel.com>,
	intel-gfx <intel-gfx@...ts.freedesktop.org>
Subject: Re: Critical regression in 4.7-rcX

On 07/15/2016 09:43 AM, Ville Syrjälä wrote:
> On Fri, Jul 15, 2016 at 04:27:27PM +0200, Daniel Vetter wrote:
>> On Fri, Jul 15, 2016 at 8:55 AM, Linus Torvalds
>> <torvalds@...ux-foundation.org> wrote:
>>> On Thu, 14 Jul 2016, Larry Finger wrote:
>>>> To anyone keeping track of regressions in kernel 4.7, I call your attention to
>>>> https://bugs.freedesktop.org/show_bug.cgi?id=96675.
>>>>
>>>> This bug causes driver i915 to fail to connect to the display, and results in
>>>> a blank screen as soon as the kernel is loaded. The only way to operate with
>>>> kernel 4.7 is to add "nomodeset" to the command line. The problem was bisected
>>>> to commit f21a21983ef13a ("drm/i915: Splitting intel_dp_detect").
>>>
>>> Daniel? Jani? Time to revert?
>>
>> Yup. Means that I'll get to revert a pile of patches (plus even more
>> in -next), but that's what we get for not handling regressions timely.
>> Dave poked me about the same bug already too. But will take a few days
>> until the pull is in your inbox I guess.
>
> I attached a oneliner to the bug today, that I *think* should fix the
> problem.

After I checked out the problem commit and built that kernel with the one-line 
patch, the display works; however, mainline still fails. I am currently 
bisecting to find what other commit fails. At a minimum, we should be able to 
reduce the number of commits that need reverting.

Larry