Red Hat Bugzilla – Bug 193961
ACPI "Large Reference Count" causes infinite loop when AC unplugged
Last modified: 2007-11-30 17:11:34 EST
Description of problem:
ACPI subsystem seems to get stuck on certain events, rendering the system useless.
Version-Release number of selected component (if applicable):
Sporadically. Never showed up with 2.6.15 kernels (based on ACPI
Steps to Reproduce:
1. Unplug AC.
CPU load shoots up pretty much 100% system time. Everything else falls to
pieces. System is still "running", but impossible to shut down elegantly. ACPI
interpreter seems to be caught in a loop.
Reviewing system logs reveals a slew of "ACPI Warning (utdelete-0378): Large
Reference Count (362E) in object dab92254 " error messages.
System processes AC event as it should.
Because of quirks in the BIOS and acpi-cpufreq, acpi-cpufreq is reloaded on
power-change events so the new set of frequncies is picked up.
No problems with earlier kernels with ACPI 20050902, but ACPI 20060127 seems to
be rather sketchy on this notebook.
Created attachment 130449 [details]
System log excerpt
still happening with the 2.6.17 update ?
I've not seen it with 2.6.17 yet (between hibernates the latest kernel has been
"up" 12 days now), but this is perhaps because I've booted it with ec_intr=0.
[This comment added as part of a mass-update to all open FC4 kernel bugs]
FC4 has now transitioned to the Fedora legacy project, which will continue to
release security related updates for the kernel. As this bug is not security
related, it is unlikely to be fixed in an update for FC4, and has been migrated
Please retest with Fedora Core 5.
A new kernel update has been released (Version: 2.6.18-1.2200.fc5)
based upon a new upstream kernel release.
Please retest against this new kernel, as a large number of patches
go into each upstream release, possibly including changes that
may address this problem.
This bug has been placed in NEEDINFO state.
Due to the large volume of inactive bugs in bugzilla, if this bug is
still in this state in two weeks time, it will be closed.
Should this bug still be relevant after this period, the reporter
can reopen the bug at any time. Any other users on the Cc: list
of this bug can request that the bug be reopened by adding a
comment to the bug.
In the last few updates, some users upgrading from FC4->FC5
have reported that installing a kernel update has left their
systems unbootable. If you have been affected by this problem
please check you only have one version of device-mapper & lvm2
installed. See bug 207474 for further details.
If this bug is a problem preventing you from installing the
release this version is filed against, please see bug 169613.
If this bug has been fixed, but you are now experiencing a different
problem, please file a separate bug for the new problem.
This bug has been mass-closed along with all other bugs that
have been in NEEDINFO state for several months.
Due to the large volume of inactive bugs in bugzilla, this
is the only method we have of cleaning out stale bug reports
where the reporter has disappeared.
If you can reproduce this bug after installing all the
current updates, please reopen this bug.
If you are not the reporter, you can add a comment requesting
it be reopened, and someone will get to it asap.
Created attachment 142110 [details]
Typical ACPI large reference count messages
Seen again in kernel-2.6.18-1.2849.fc6. Again, happened as the battery was
removed. It didn't crash the system, but the flurry of messages made is pretty
much unusable. Kernel booted with ec_intr=0.
acpi_serialize seems to have calmed this.
if it is necessary to add "acpi_serialize" to the cmdline
to make the machine boot and run properly, that is a serious bug.
Please file it at bugzilla.kernel.org