[ add Andrew ] On Thu, Feb 4, 2021 at 6:40 PM Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx> wrote: > > Differentiate between hardware not supporting hugepages and user disabling THP > via 'echo never > /sys/kernel/mm/transparent_hugepage/enabled' > > For the devdax namespace, the kernel handles the above via the > supported_alignment attribute and failing to initialize the namespace > if the namespace align value is not supported on the platform. > > For the fsdax namespace, the kernel will continue to initialize > the namespace. This can result in the kernel creating a huge pte > entry even though the hardware don't support the same. > > We do want hugepage support with pmem even if the end-user disabled THP > via sysfs file (/sys/kernel/mm/transparent_hugepage/enabled). Hence > differentiate between hardware/firmware lacking support vs user-controlled > disable of THP and prevent a huge fault if the hardware lacks hugepage > support. Looks good to me. Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx> I assume this will go through Andrew.
