2017-05-10 23:09 GMT+03:00 Guenter Roeck <li...@roeck-us.net>:
> On Wed, May 10, 2017 at 10:16:33PM +0300, Tommi Rantala wrote:
>> 2017-05-10 17:30 GMT+03:00 Thomas Gleixner <t...@linutronix.de>:
>> > 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.rant...@gmail.com>
>> > Signed-off-by: Thomas Gleixner <t...@linutronix.de>
>>
>> Many thanks, I can confirm that it works well!
>>
> Ok if I add your Tested-by: ?Sure! Tested-by: Tommi Rantala <tt.rant...@gmail.com> > 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;
