https://bugs.freedesktop.org/show_bug.cgi?id=29062
Summary: hp dv5000: xpress 200m 5955 + KMS does not resume from suspend Product: DRI Version: XOrg CVS Platform: x86-64 (AMD64) OS/Version: Linux (All) Status: NEW Severity: normal Priority: medium Component: DRM/Radeon AssignedTo: dri-devel@lists.freedesktop.org ReportedBy: acimmarusti@gmail.com
Created an attachment (id=37046) --> (https://bugs.freedesktop.org/attachment.cgi?id=37046) dmesg just after failed resume
When I try suspending using KMS my computer (an HP Pavilion dv5035nr laptop) does not resume. Furthermore I've tried logging into it remotely to obtain a backtrace from X with no success (following this procedure: http://ubuntuforums.org/showthread.php?t=1228332). I'm letting NetworkManager handle my network interfaces, however, I also tried using dhcp directly in the /etc/network/interfaces file. The laptop screen is completely blank so I can't switch to another session. The keyboard doesn't respond so it seems like the kernel crashed.
When using UMS the resume process happens perfectly.
I dedicated a large portion of the day to finding a clue to this one. Following this advice: http://lxr.linux.no/#linux+v2.6.34.1/Documentation/power/s2ram.txt I was able to extract a trace from the failed resume process:
Magic number: 0:981:799 hash matches drivers/base/power/main.c:523 pci 0000:01:05.0: hash matches ec PNP0C09:00: hash matches
The first hash match is none other than my ATI Radeon card as I easily verified with lspci:
01:05.0 VGA compatible controller: ATI Technologies Inc Radeon XPRESS 200M 5955 (PCIE)
However, the above link says that the likely culprit in the failed resume process is the last hash match. This corresponds to the EC driver: http://lxr.free-electrons.com/source/drivers/acpi/ec.c
My card was, till recently, listed under embedded graphics at the AMD/ATI website. So there appears to be some conflict when using KMS between radeon and ec that causes the kernel to hang (that explains why I can't ssh into my computer to get a trace).
I would appreciate some advice and guidance in further debugging this issue, since I'm flying half-blind. I have compiled my kernel with support for ACPI_DEBUG and I included a quirk David Airlie used to get suspend to work with a HP nx6125 laptop but applied for my model (http://git.kernel.org/?p=linux/kernel/git/airlied/drm-2.6.git;a=commit;h=580...)