insmod: error inserting '/lib/dm-region-hash.ko': -1 File exists

If you compile the latest kernel version on CentOS you may get this error message and kernel panic:


insmod: error inserting '/lib/dm-region-hash.ko': -1 File exists
mount: could not find filesystem '/dev/root'


What do you ?


1) Compile again the kernel but add the following variable in the .config file


     CONFIG_SYSFS_DEPRECATED_V2=y


2) Compile kerne again:
     make; make modules ; make modules_install ; make install


3) The command make install installs the new kernel on /boot, grub config file also is updated.


4) restart, you may get this error "insmod: error inserting '/lib/dm-region-hash.ko': -1 File exists" , don't worry about it, you may get this error because the kernel module dm-region-hash.ko is loaded two times.


That's all folks !!!