kernel-packages team mailing list archive

[Colin Ian King <1524930@xxxxxxxxxxxxxxxxxx>]

Before fix (3.19.0-43-generic):

dmesg | grep "ACPI PCC"
[    0.777442] ACPI PCC probe failed.

With fix: (3.19.0-46-generic)

dmesg | grep "ACPI PCC"

So verified it is now fixed with the -proposed kernel


** Tags removed: verification-needed-vivid
** Tags added: verification-done-vivid

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1524930

Title:
  "ACPI PCC probe failed" message is an error message when it should be
  debug

Status in linux package in Ubuntu:
  In Progress
Status in linux source package in Vivid:
  Fix Committed

Bug description:
  [SRU Justification][Vivid]

  Users of Ubuntu Vivid are seeing a seemingly alarming kernel failure
  message "ACPI PCC probe failed" when in fact it is just a debug
  message informing the kernel developers that a probe for an ACPI PCC
  mailbox was not successful (which is just a debug only message) and
  not a failure one needs to worry about.   This message is asked about
  frequently on askubuntu.com, so it is alarming quite a few users, c.f.
  : http://askubuntu.com/questions/708215/1-037533-acpi-pcc-probe-
  failed.

  This fix landed in Wily, and the driver with the alarming message only
  affects Vivid.

  [Fix]
  Upstream commit efd756daf4ddae3cec2404c4e0b680b7cfdd6a45 ("ACPI / PCC: Use pr_debug() for debug messages in pcc_init()")

  [Testcase]

  Boot a machine without the PCC feature, without the fix one sees the
  error message in the kernel log. With the fix, this error is now a
  warning.  Note: This only affects Vivid.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1524930/+subscriptions