linux-kernel - Re: i915 wakes from suspend to RAM with blank screen after commit cd9dde44f47501394b9f0715b6a36a92aa74c0d0

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: <86hazokcb7.fsf@sumi.keithp.com>
Date:	Sat, 21 Jan 2012 12:53:00 -0800
From:	Keith Packard <keithp@...thp.com>
To:	Lubos Kolouch <lubos.kolouch@...il.com>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: i915 wakes from suspend to RAM with blank screen after commit cd9dde44f47501394b9f0715b6a36a92aa74c0d0

On Sat, 21 Jan 2012 19:44:53 +0100, Lubos Kolouch <lubos.kolouch@...il.com> wrote:

> dmesg after boot - http://paste.pocoo.org/show/538343/
> dmesg after failed resume -  http://paste.pocoo.org/show/538344/

Ok, that's weird -- we're choosing a different display port link speed
on resume than at boot time. I have a theory that intel_dp_mode_fixup is
accidentally using the current bpp value when computing the values
needed for the new mode, and that this value may differ between boot and
resume.

Here's a patch to dump some debug info out to test this theory.

Content of type "application/pgp-signature" skipped

View attachment "0001-drm-i915-Output-a-bit-of-debug-info-for-display-port.patch" of type "text/x-diff" (1411 bytes)

Please try this on the broken kernel, sending along the dmesg output at
boot and resume time again.

-- 
keith.packard@...el.com