On Tue, Aug 13, 2019 at 05:57:32PM +1000, Stephen Rothwell wrote: > Hi all, > > After merging the rcu tree, today's linux-next build (powerpc allnoconfig) > failed like this: > > drivers/base/core.c: In function 'device_links_read_lock_held': > drivers/base/core.c:106:9: error: implicit declaration of function 'lock_is_held'; did you mean 'lockref_get'? [-Werror=implicit-function-declaration] > return lock_is_held(&device_links_lock); > ^~~~~~~~~~~~ > lockref_get > > Caused by commit > > 4a3a5474b4c1 ("driver/core: Convert to use built-in RCU list checking") > > lock_is_held() us only available if CONFIG_LOCKDEP is set. Joel, one approach would be to make lock_is_held() variant of device_links_read_lock_held() be a macro rather than a function. Another would be to use #ifdef so as to invoke lock_is_held() only when lockdep is enabled. Or do you have a better approach? Thanx, Paul > I have reverted that commit for today. > > -- > Cheers, > Stephen Rothwell