<=xf86-video-nouveau-0.0.16_pre20101130 >=gentoo-sources-2.6.35-r13 xf86-video-intel-2.14.0.ebuild >=libdrm-2.4.22 Any operation involving switch through /sys/kernel/debug/vgaswitcheroo/switch as described in http://en.gentoo-wiki.com/wiki/Vga_switcheroo immediately hangs the machine either when X is running or X is restarted. If it can help, a distribution where this (partially) works is ubuntu 10.10. The "partially" refers to the fact that the machine crashes whenever suspend or hibernate is performed after a switch. acpi_call method described here http://linux-hybrid-graphics.blogspot.com/2010/07/using-acpicall-module-to-switch-onoff.html has the same behaviour. NOTE: I do not know whether the issue is related to nouveau kernel module or x86-video-nouveau, but disabling the nouveau module from the kernel build option makes acpi_call work, as long as the switch off of the NVidia card is concerned. NOTE2: As to suspend/hibernate/resume/reboot, acpi_call without nouveau kernel module seems not to interfere with system stability when suspending/hibernating and then resuming, but: a) on resume, both calls echo "ON" > /proc/acpi/acpi_call echo "OFF" > /proc/acpi/acpi_call are necessary (echo "OFF" > /proc/acpi/acpi_call is not enough) to turn off again the NVidia card, that means that on resume the state of the card is not restored to off and that the echo "OFF" alone is not enough to turn it off. b) if I reboot, I am not able to turn off Nvidia by using echo "OFF" > /proc/acpi/acpi_call but if I shutdown and then echo "OFF" > ... it's ok again. Hope it helps solving the issue. Hardware: ASUS U30JC intel i915 + nvidia Optimus. Thanks in advance. Giacomo Elettra Synchrotron Radiation Facility Trieste, Italy Reproducible: Always Steps to Reproduce: See above
Was the issue already reported to kernel or freedesktop bugzilla? If yes, then please add the URL to the bug.
Hi. Yes the problem has been already discussed in different places: 1. kernel mailing lists http://kerneltrap.org/mailarchive/linux-kernel/2010/12/10/4657804 2. dri-devel mailing lists (with subsequent discussion with Dave Airlie) http://www.mail-archive.com/dri-devel@lists.freedesktop.org/msg06098.html 3. acpi mailing lists http://comments.gmane.org/gmane.linux.acpi.devel/48758 Up to now, I cannot understand the reason why in ubuntu 10.10 it partially works. I checked the kernel configuration many times and, as to graphics support and acpi, they appear to be equivalent (nouveau and i915 built as modules, same options enabled...) the difference is in the version of the xf86-video-nouveau (and maybe intel and drm) installed by 10.10 and gentoo. Another detail: it is very difficult to catch any debug info. I got it once and it said something about PFIFO_CACHE_ERROR - Ch %d/%d Mthd 0x%04x Data 0x%08x\n (with integers and pointer addresses in place of %d and %h) and, just before dying: [drm] nouveau 0000:01:00.0: PFIFO still angry after 101 spins, halt Thanks for your interest. Any hint to reproduce the (partially) working behaviour of ubuntu is appreciated (since I love gentoo...). The problems concerning hibernate, suspend and resume still persist in both versions. Giacomo
I can confirm the behaviour with 2.6.37 gentoo sources. Some more details: without compiling nouveau module (I just wanted to be able to switch off nvidia card) 2.6.35 works with acpi_call module (card seems to switch off, I gain 4 watts of power). 2.6.37 + acpi_call, used in the same way as 2.6.35 hangs again the machine. So I must stay with 2.6.35.
We'll follow the upstream bug.
