I recently updated to 12.04 from 11.10 and the problem still existed even with the 3.4 kernel.
Disabling ACPI solved the problem but then the CPUs were running at full speed. As a Workaround I found this: https://wiki.ubuntu.com/DebuggingACPI#Trouble_Booting and booting with acpi=noirq worked for me. $ uname -a Linux Trifix 3.4.0-030400rc5-generic #201205011817 SMP Tue May 1 22:18:19 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux top: top - 12:28:01 up 21 min, 1 user, load average: 0.50, 0.40, 0.26 Tasks: 178 total, 1 running, 177 sleeping, 0 stopped, 0 zombie Cpu(s): 0.3%us, 0.2%sy, 0.0%ni, 98.7%id, 0.8%wa, 0.0%hi, 0.0%si, 0.0%st Mem: 6094080k total, 952640k used, 5141440k free, 90032k buffers Swap: 6269948k total, 0k used, 6269948k free, 403796k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1998 alex 20 0 394m 11m 8304 S 2 0.2 0:06.51 multiload-apple 2551 alex 20 0 742m 153m 35m S 2 2.6 0:15.86 firefox 1 root 20 0 24432 2408 1352 S 0 0.0 0:01.00 init 2 root 20 0 0 0 0 S 0 0.0 0:00.00 kthreadd 3 root 20 0 0 0 0 S 0 0.0 0:00.09 ksoftirqd/0 6 root RT 0 0 0 0 S 0 0.0 0:00.00 migration/0 7 root RT 0 0 0 0 S 0 0.0 0:00.00 watchdog/0 8 root RT 0 0 0 0 S 0 0.0 0:00.00 migration/1 9 root 20 0 0 0 0 S 0 0.0 0:00.10 kworker/1:0 10 root 20 0 0 0 0 S 0 0.0 0:00.10 ksoftirqd/1 12 root RT 0 0 0 0 S 0 0.0 0:00.00 watchdog/1 13 root RT 0 0 0 0 S 0 0.0 0:00.00 migration/2 14 root 20 0 0 0 0 S 0 0.0 0:00.00 kworker/2:0 15 root 20 0 0 0 0 S 0 0.0 0:00.06 ksoftirqd/2 16 root RT 0 0 0 0 S 0 0.0 0:00.00 watchdog/2 The Computer is a Lenovo Y560p. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/717919 Title: ACPI + kworker high interrupts. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/717919/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
