On 9/1/22 11:45 AM, Huang, Ying wrote: > "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx> writes: > >> With multiple dax devices having the same node affinity, the kernel wrongly assigned >> default_dram memory type to some devices after the memory hotplug operation. Fix this by >> not clearing node_memory_types on the dax device remove. > > Sorry for late reply. > > Just for confirmation. There are multiple dax devices in one NUMA node? > > If you can show the bug reproducing steps, that will make it even easier > to understand. > NUMA nodes are assigned per region and you can have multiple devdax namespace with same NUMA node affinity. dax0.1 and dax0.2 are examples. To recreate you can follow the below steps root@ubuntu-guest:/sys/devices/system/node/node3# ls compact cpumap meminfo memory34 memory36 memory38 memory41 memory43 memory45 memory47 memory50 memory52 memory54 numastat uevent cpulist distance memory33 memory35 memory37 memory39 memory42 memory44 memory46 memory49 memory51 memory53 memory55 subsystem vmstat root@ubuntu-guest:/sys/devices/system/node/node3# root@ubuntu-guest:/sys/devices/system/node/node3# for mem in memory*; do echo 0 > $mem/online; done root@ubuntu-guest:/sys/devices/system/node/node3# cd /sys/bus/dax/drivers root@ubuntu-guest:/sys/bus/dax/drivers# echo dax0.0 > kmem/unbind root@ubuntu-guest:/sys/bus/dax/drivers# cd /sys/devices/system/node/node3/ root@ubuntu-guest:/sys/devices/system/node/node3# ls compact cpumap meminfo memory42 memory44 memory46 memory49 memory51 memory53 memory55 subsystem vmstat cpulist distance memory41 memory43 memory45 memory47 memory50 memory52 memory54 numastat uevent root@ubuntu-guest:/sys/devices/system/node/node3# for mem in memory*; do echo 1 > $mem/online; done -aneesh
