https://bugzilla.kernel.org/show_bug.cgi?id=56591
Summary: HP/Compaq NC6000 fan speed regression on 3.7+ Product: ACPI Version: 2.5 Kernel Version: 3.7+ Platform: All OS/Version: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: Power-Thermal AssignedTo: acpi_power-ther...@kernel-bugs.osdl.org ReportedBy: syrj...@sci.fi CC: rui.zh...@intel.com Regression: Yes Created an attachment (id=98531) --> (https://bugzilla.kernel.org/attachment.cgi?id=98531) Logs and dumps from 3.7.10 and 3.9-rc6 kernels There's a regression in thermal subsystem in 3.7 kernel, which results in fan speed staying after during resume. Other people have seen the problem, although it may be that the exact nature of the bug is a bit different between different machines. Here are the mailing list references: https://lkml.org/lkml/2013/3/2/171 https://lkml.org/lkml/2013/4/13/142 For me on 3.7.10 the symptoms of the bug depend on whether I resume the laptop when it's totally cooled down, or still warm. When the bug occurs, the reported temperature somehow goes out of sync with the trip points, and the cooling device cur_state doesn't always match the fan speed. On 3.9-rc6, there's actually another regression, which causes the fan speed to misbehave already without any suspend/resume cycles. What happens is that the fan speeds up when the temperature rises, but when the temperature comes back down, the fan doesn't slow down. When cooling down, the temperature of the trip points does seem to change due to hysteresis, so some activity happens when the trip points are reached, but somehow the cooling devices don't get turned off. The cooling device cur_state accurately reflects the fan speed in this case. I also tested git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux.git thermal but it appears to behave exactly like 3.9-rc6. I've attached a tarball with logs from both bug scenarios on a 3.7.10 kernel. I've included logs from a 3.9-rc6 kernel as well, but as stated you don't actually need to suspend/resume to trigger the misbehavior on 3.9-rc6. The "desc.txt" files inside the tarball describe the steps I took when I collected the logs. The tarball also contains acpidump output. -- Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are watching the assignee of the bug. ------------------------------------------------------------------------------ Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis & visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter _______________________________________________ acpi-bugzilla mailing list acpi-bugzilla@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/acpi-bugzilla