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The > md_open shouldn't create mddev when all_mddevs list doesn't contain > mddev. With currently code logic, there will be very easy to trigger > soft lockup in non-preempt env. > > *** env *** > kvm-qemu VM 2C1G with 2 iscsi luns > kernel should be non-preempt > > *** script *** > > about trigger 1 time with 10 tests > > ``` > 1 node1="15sp3-mdcluster1" > 2 node2="15sp3-mdcluster2" > 3 > 4 mdadm -Ss > 5 ssh ${node2} "mdadm -Ss" > 6 wipefs -a /dev/sda /dev/sdb > 7 mdadm -CR /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda \ > /dev/sdb --assume-clean > 8 > 9 for i in {1..100}; do > 10 echo ==== $i ====; > 11 > 12 echo "test ...." > 13 ssh ${node2} "mdadm -A /dev/md0 /dev/sda /dev/sdb" > 14 sleep 1 > 15 > 16 echo "clean ....." > 17 ssh ${node2} "mdadm -Ss" > 18 done > ``` > the non-clustered test script. (again: run on non-preempt kernel) ``` #!/bin/bash mdadm -Ss wipefs -a /dev/sda /dev/sdb mdadm -CR /dev/md0 -b internal -e 1.2 -n 2 -l mirror /dev/sda /dev/sdb --assume-clean sleep 5 mdadm -Ss for i in {1..200}; do echo ==== $i ====; echo "test ...." mdadm -A /dev/md0 /dev/sda /dev/sdb sleep 1 echo "clean ....." mdadm -Ss done ``` the value N on "/sys/module/md_mod/parameters/create_on_open" is useless. Thanks, heming