In r5c_journal_mode_show(), it is necessary to call mddev_lock()
before accessing conf and conf->log. Otherwise, the conf->log
may change (and become NULL).
Signed-off-by: NSong Liu <songliubraving@fb.com>
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NShaohua Li <shli@fb.com>