On Wed 12-10-16 16:44:31, zijun_hu wrote: > On 10/12/2016 04:25 PM, Michal Hocko wrote: > > On Wed 12-10-16 15:24:33, zijun_hu wrote: [...] > >> i found the following code segments in mm/vmalloc.c > >> static struct vmap_area *alloc_vmap_area(unsigned long size, > >> unsigned long align, > >> unsigned long vstart, unsigned long vend, > >> int node, gfp_t gfp_mask) > >> { > >> ... > >> > >> BUG_ON(!size); > >> BUG_ON(offset_in_page(size)); > >> BUG_ON(!is_power_of_2(align)); > > > > See a recent Linus rant about BUG_ONs. These BUG_ONs are quite old and > > from a quick look they are even unnecessary. So rather than adding more > > of those, I think removing those that are not needed is much more > > preferred. > > > i notice that, and the above code segments is used to illustrate that > input parameter checking is necessary sometimes Why do you think it is necessary here? -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>