Comment 114 for bug 439138

Having this same issue of high cpu usage since this morning after several updates including misc x stuff such as libmesa and also some linuxheaders.

Tried the logout, log back in. Nothing.
Read about this being only for Intel chipset/graphics, I have a weird ATI chipset/Nvidia graphics combo, so no dice. Also no SSD.
Read about cryptdisk having something to do about it but I dont have it installed (nor was it ever installed), so nothing again.

One thing in common with others, been having some issues with splash in boot for a couple of days now, first it would give me some garbage and stop the boot process. Then after some updates it apparently got better, still garbage but would eventually get GDM.
Disabled it from the kernel boot line and everything seemed ok, until this mornings updates.

So I can login, did a workaround, started in recovery mode, logged console style, no gdm. Startx gives me my desktop, but again with the high cpu usage, as far as I know GDM is not around so I would dare say is not GDM but X.

Something funny happened in one of my attempts to fix this. I was browsing, looking for alternatives, reading this thread, spent some minutes working while enduring the high cpu usage.
Went to reboot and Gnome asked -via a dialog- if I was sure, because an unknow program was working. The moment this dialog showed up CPU usage dropped to normal. Click cancel, go back to desktop and for a couple of seconds everything remained nominal, but after a couple of clicks here and there CPU usage went back to high.
Tried to repeat the whole reboot process but this time I didnt get a question and so the computer went ahead with the reboot.

Very funky stuff.