On 4/21/20 2:51 PM, Dan Carpenter wrote: > It turns out there aren't that many of these in xen. > > $ grep IS_ERR_OR_NULL drivers/gpu/drm/xen/ -Rn > drivers/gpu/drm/xen/xen_drm_front_kms.c:63: if (IS_ERR_OR_NULL(fb)) > drivers/gpu/drm/xen/xen_drm_front_gem.c:86: if (IS_ERR_OR_NULL(xen_obj)) > drivers/gpu/drm/xen/xen_drm_front_gem.c:120: if (IS_ERR_OR_NULL(xen_obj->pages)) { > drivers/gpu/drm/xen/xen_drm_front_gem.c:139: if (IS_ERR_OR_NULL(xen_obj)) > drivers/gpu/drm/xen/xen_drm_front_gem.c:197: if (IS_ERR_OR_NULL(xen_obj)) > drivers/gpu/drm/xen/xen_drm_front.c:403: if (IS_ERR_OR_NULL(obj)) { > > They're all wrong, because if the pointer was really NULL then it's > not handled correctly and would eventually lead to a runtime failure. It seems that you were right and I can simply change all IS_ERR_OR_NULL to just IS_ERR I am planning a series of patches later on, so I'll include this fix as well > > Normally Smatch is smart enough to know that the pointer isn't NULL so > it doesn't generate a warning but yesterday I introduced a bug in Smatch > by mistake. It's fixed now. > > regards, > dan carpenter > Thank you, Oleksandr