A mis-spelled config option (was it spelled that way in the past?)
eliminated kmap_atomic_prot_pfn from core DRM.
-#if (defined(CONFIG_X86) && defined(CONFIG_X86_32) && defined(CONFIG_HIMEM))
+#if (defined(CONFIG_X86) && defined(CONFIG_X86_32) && defined(CONFIG_HIGHMEM))
#define DRM_KMAP_ATOMIC_PROT_PFN
extern void *kmap_atomic_prot_pfn(unsigned long pfn, enum km_type type,
pgprot_t protection);
#define DRM_KMAP_ATOMIC_PROT_PFN
extern void *kmap_atomic_prot_pfn(unsigned long pfn, enum km_type type,
pgprot_t protection);