On Wed, May 10, 2017 at 10:16:33PM +0300, Tommi Rantala wrote: > 2017-05-10 17:30 GMT+03:00 Thomas Gleixner <tglx@xxxxxxxxxxxxx>: > > The recent conversion to the hotplug state machine missed that the original > > hotplug notifiers did not execute in the frozen state, which is used on > > suspend on resume. > > > > This does not matter on single socket machines, but on multi socket systems > > this breaks when the device for a non-boot socket is removed when the last > > CPU of that socket is brought offline. The device removal locks up the > > machine hard w/o any debug output. > > > > Prevent executing the hotplug callbacks when cpuhp_tasks_frozen is true. > > > > Thanks to Tommi for providing debug information patiently while I failed to > > spot the obvious. > > > > Fixes: e00ca5df37ad ("hwmon: (coretemp) Convert to hotplug state machine") > > Reported-by: Tommi Rantala <tt.rantala@xxxxxxxxx> > > Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > > Many thanks, I can confirm that it works well! > Ok if I add your Tested-by: ? Thanks, Guenter > -Tommi > > > --- > > drivers/hwmon/coretemp.c | 14 ++++++++++++++ > > 1 file changed, 14 insertions(+) > > > > --- a/drivers/hwmon/coretemp.c > > +++ b/drivers/hwmon/coretemp.c > > @@ -605,6 +605,13 @@ static int coretemp_cpu_online(unsigned > > struct platform_data *pdata; > > > > /* > > + * Don't execute this on resume as the offline callback did > > + * not get executed on suspend. > > + */ > > + if (cpuhp_tasks_frozen) > > + return 0; > > + > > + /* > > * CPUID.06H.EAX[0] indicates whether the CPU has thermal > > * sensors. We check this bit only, all the early CPUs > > * without thermal sensors will be filtered out. > > @@ -654,6 +661,13 @@ static int coretemp_cpu_offline(unsigned > > struct temp_data *tdata; > > int indx, target; > > > > + /* > > + * Don't execute this on suspend as the device remove locks > > + * up the machine. > > + */ > > + if (cpuhp_tasks_frozen) > > + return 0; > > + > > /* If the physical CPU device does not exist, just return */ > > if (!pdev) > > return 0; -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html