3 files changed, 17 insertions, 8 deletions

diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h
index 8af276361bf2..37b82cb96c89 100644
--- a/include/asm-generic/bug.h
+++ b/include/asm-generic/bug.h
@@ -28,6 +28,17 @@ struct bug_entry {
 #define BUGFLAG_WARNING (1<<0)
 #endif  /* CONFIG_GENERIC_BUG */
 
+/*
+ * Don't use BUG() or BUG_ON() unless there's really no way out; one
+ * example might be detecting data structure corruption in the middle
+ * of an operation that can't be backed out of.  If the (sub)system
+ * can somehow continue operating, perhaps with reduced functionality,
+ * it's probably not BUG-worthy.
+ *
+ * If you're tempted to BUG(), think again:  is completely giving up
+ * really the *only* solution?  There are usually better options, where
+ * users don't need to reboot ASAP and can mostly shut down cleanly.
+ */
 #ifndef HAVE_ARCH_BUG
 #define BUG() do { \
         printk("BUG: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \
@@ -39,6 +50,12 @@ struct bug_entry {
 #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while(0)
 #endif
 
+/*
+ * WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report
+ * significant issues that need prompt attention if they should ever
+ * appear at runtime.  Use the versions with printk format strings
+ * to provide better diagnostics.
+ */
 #ifndef __WARN
 #ifndef __ASSEMBLY__
 extern void warn_slowpath(const char *file, const int line,
diff --git a/include/asm-generic/local.h b/include/asm-generic/local.h
index 33d7d04e4119..dbd6150763e9 100644
--- a/include/asm-generic/local.h
+++ b/include/asm-generic/local.h
@@ -2,7 +2,6 @@
 #define _ASM_GENERIC_LOCAL_H
 
 #include <linux/percpu.h>
-#include <linux/hardirq.h>
 #include <asm/atomic.h>
 #include <asm/types.h>
 
diff --git a/include/asm-generic/memory_model.h b/include/asm-generic/memory_model.h
index 36fa286adad5..4c8d0afae711 100644
--- a/include/asm-generic/memory_model.h
+++ b/include/asm-generic/memory_model.h
@@ -69,15 +69,8 @@
 })
 #endif /* CONFIG_FLATMEM/DISCONTIGMEM/SPARSEMEM */
 
-#ifdef CONFIG_OUT_OF_LINE_PFN_TO_PAGE
-struct page;
-/* this is useful when inlined pfn_to_page is too big */
-extern struct page *pfn_to_page(unsigned long pfn);
-extern unsigned long page_to_pfn(struct page *page);
-#else
 #define page_to_pfn __page_to_pfn
 #define pfn_to_page __pfn_to_page
-#endif /* CONFIG_OUT_OF_LINE_PFN_TO_PAGE */
 
 #endif /* __ASSEMBLY__ */