On Wed, Jun 06, 2018 at 11:38:46AM -0500, Jeremy Linton wrote: > The numa mask subset check can often lead to system hang or crash during > CPU hotplug and system suspend operation if NUMA is disabled. This is > mostly observed on HMP systems where the CPU compute capacities are > different and ends up in different scheduler domains. Since > cpumask_of_node is returned instead core_sibling, the scheduler is > confused with incorrect cpumasks(e.g. one CPU in two different sched > domains at the same time) on CPU hotplug. > > Lets disable the NUMA siblings checks for the time being, as NUMA in > socket machines have LLC's that will assure that the scheduler topology > isn't "borken". > > The NUMA check exists to assure that if a LLC within a socket crosses > NUMA nodes/chiplets the scheduler domains remain consistent. This code will > likely have to be re-enabled in the near future once the NUMA mask story > is sorted. At the moment its not necessary because the NUMA in socket > machines LLC's are contained within the NUMA domains. > > Further, as a defensive mechanism during hot-plug, lets assure that the > LLC siblings are also masked. > > Reported-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> > Reviewed-by: Sudeep Holla <sudeep.holla@xxxxxxx> > Signed-off-by: Jeremy Linton <jeremy.linton@xxxxxxx> Thanks for this. I queued it for this merging window. -- Catalin -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
