crash on create/destroy namespace

[Sean58238]

1 issue There is a probability that ndctl can crash during stress test. Udev：KERNEL=="dax*",SUBSYSTEMS=="nd", ATTRS{uuid}=="?*", SYMLINK+="disk/by-id/dax-$attr{uuid}" crash> bt PID: 94249 TASK: ffff88c45f708000 CPU: 1 COMMAND: "systemd-udevd" #0 [ffffc90021ed3490] machine_kexec at ffffffff8106002b #1 [ffffc90021ed34e8] __crash_kexec at ffffffff81139ab2 #2 [ffffc90021ed35b8] crash_kexec at ffffffff8113adbc #3 [ffffc90021ed35d8] oops_end at ffffffff81024fd1 #4 [ffffc90021ed3600] no_context at ffffffff8106d2f2 #5 [ffffc90021ed3670] __bad_area_nosemaphore at ffffffff8106d680 #6 [ffffc90021ed36c8] bad_area_nosemaphore at ffffffff8106d826 #7 [ffffc90021ed36d8] do_kern_addr_fault at ffffffff8106d92a #8 [ffffc90021ed3700] __do_page_fault at ffffffff8106dcb7 #9 [ffffc90021ed3768] do_page_fault at ffffffff8106ddf0 #10 [ffffc90021ed37a0] page_fault at ffffffff81c010a4 [exception RIP: memcpy_erms+6] RIP: ffffffff81b4f866 RSP: ffffc90021ed3858 RFLAGS: 00010246 RAX: ffff8884a1aa7000 RBX: 0000000000001000 RCX: 0000000000001000 RDX: 0000000000001000 RSI: ffffc90080200000 RDI: ffff8884a1aa7000 RBP: ffffc90021ed38f8 R8: ffff88c45f708000 R9: 0000000000001000 R10: 0000000000000000 R11: 000000001286a9c0 R12: 0000000000000000 R13: 0000000000001000 R14: 0000000000001000 R15: ffffc90080200000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #11 [ffffc90021ed3858] pmem_do_bvec at ffffffff815fbf59 #12 [ffffc90021ed3900] pmem_rw_page at ffffffff815fc24b #13 [ffffc90021ed3928] bdev_read_page at ffffffff812defa6 #14 [ffffc90021ed3958] do_mpage_readpage at ffffffff812e73f4 #15 [ffffc90021ed3a20] mpage_readpages at ffffffff812e76b9 #16 [ffffc90021ed3af8] blkdev_readpages at ffffffff812df51d #17 [ffffc90021ed3b08] read_pages at ffffffff811f6fb7 #18 [ffffc90021ed3b88] __do_page_cache_readahead at ffffffff811f72bf #19 [ffffc90021ed3c28] force_page_cache_readahead at ffffffff811f7730 #20 [ffffc90021ed3c60] page_cache_sync_readahead at ffffffff811f7826 #21 [ffffc90021ed3c98] generic_file_buffered_read at ffffffff811eb9f4 #22 [ffffc90021ed3da0] generic_file_read_iter at ffffffff811ede20 #23 [ffffc90021ed3de8] blkdev_read_iter at ffffffff812df6d7 #24 [ffffc90021ed3df8] new_sync_read at ffffffff8129662a #25 [ffffc90021ed3e90] __vfs_read at ffffffff81298ef9 #26 [ffffc90021ed3ea0] vfs_read at ffffffff81298f9e #27 [ffffc90021ed3ed8] ksys_read at ffffffff81299301 #28 [ffffc90021ed3f18] __x64_sys_read at ffffffff8129938a #29 [ffffc90021ed3f28] do_syscall_64 at ffffffff810029cf #30 [ffffc90021ed3f50] entry_SYSCALL_64_after_hwframe at ffffffff81c0008c RIP: 00007f9ec04566f0 RSP: 00007ffc07704968 RFLAGS: 00000246 RAX: ffffffffffffffda RBX: 0000000000200000 RCX: 00007f9ec04566f0 RDX: 0000000000000400 RSI: 000055edf6bf6dd8 RDI: 0000000000000009 RBP: 000055edf6bf6db0 R8: 0000000005231994 R9: 0000000000000428 R10: 0000000000000040 R11: 0000000000000246 R12: 000055edf6bb2bf0 R13: 0000000000000400 R14: 000055edf6bb2c40 R15: 000055edf6bf6dc8 ORIG_RAX: 0000000000000000 CS: 0033 SS: 002b

2 Test scripts： #!/bin/bash k=0 while true do echo "1" >> ndlog for ((i=0;i<=7;++i)) do ndctl create-namespace -r region0 -m devdax -s 63G -n empt-0-0-$i done echo "2" >> ndlog for ((i=0;i<=7;++i)) do ndctl create-namespace -r region0 -m devdax -s 63G -n empt-0-1-$i done echo "3" >> ndlog for ((i=0;i<=7;++i)) do ndctl create-namespace -r region1 -m devdax -s 63G -n empt-1-0-$i done echo "4" >> ndlog for ((i=0;i<=7;++i)) do ndctl create-namespace -r region1 -m devdax -s 63G -n empt-1-1-$i done echo "5" >> ndlog

line=`ndctl list --namespaces  |grep '"size":66586673152'|wc -l`

if [ "$line" -ne 32 ];then
    echo "ERROR create" >> ndlog
    exit
fi
daxline=`ls /dev/disk/by-id/|grep dax|wc -l`
if [ "$daxline" -ne 32 ];then
    echo "ERROR link" >> ndlog
    exit
fi
((++k))
date >> ndlog
echo "done $k" >> ndlog
ndctl destroy-namespace all --force
[[ $? -ne 0 ]] && echo "ERROR destroy" && exit

done

Kernel: 5.4.32 ndctl : v68

[hramrach]

This is the wrong place to report. ndctl is not responsible for kernel crashes, kernel is.

Also it should be fixed with current kernel versions (such as 5.15).