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.
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
