On Tue, Mar 06, 2018 at 10:45:08AM -0800, Matthew Wilcox wrote: > On Mon, Mar 05, 2018 at 11:07:17PM +0300, Alexey Dobriyan wrote: > > ->reserved is either 0 or sizeof(struct rcu_head), can't be negative. > > Maybe make it unsigned char instead of unsigned int in case there's > anything else that could use the space? Lokks like nothing except ->red_left_pad qualifies for uint8_t.