On 09/24/2010 10:07 AM, Randy Dunlap wrote:
On Thu, 23 Sep 2010 18:31:32 +0200 Uwe Bonnes wrote:
[just adding cc's]
> "Randy" == Randy Dunlap rdunlap@xenotime.net writes: >
Randy> Is CONFIG_DRM_KMS_HELPER enabled in your kernel .config file? If Randy> not, we need to find out how to enable it (there is no kconfig Randy> prompt for it).Yes, it is enabled
Randy> Can you check if Alt-Sysrq-H (help) lists V for "force-fb(V)"?Yes, it is listed.
And yes, my last experiments where with ALT-CTL-sysreq, so doomed for non function due to operator error.
However: When running X, X.Org X Server 1.9.0 on Thinkpad R50 RV250, Alt-Sysrq-v switches to an all-black display. By console switching with ALT-CLT-F1 I get back to the booting console and ALT-CLT-F7 brings me back to X. Running on the console and calling Alt-Sysrq-v prints SysRq : Restore framebuffer console
Is there some omission by the distribution or my setup that Alt-Sysrq-v when running X results in an all-black screen?
And when I hit the hibernate problem, the screen stays black even with a console switch after Alt-Sysrq-v
I am not exactly sure what you are looking for but alt-sysrq-v might not tell you a whole lot because an escape back to the text console that was not actively receiving printk's or crash data is going to in general provide you with a black screen.
If you were interested in something a bit more invasive such as a collecting a process listing or examining the dmesg output you might consider jumping into kdb.
echo kbd > /sys/module/kgdboc/parameters/kgdboc
Then you would do the "alt-sysrq v" followed by "alt-sysrq g". From there you could then run dmesg, and your screen would no longer be blank in theory. :-)
We do have some patches for the RV250 for atomic kernel mode setting plus kdb support but they are not merged to the mainline kernels as of yet.
Jason.