1 files changed, 20 insertions, 8 deletions

diff --git a/lib/bug.c b/lib/bug.c
index 06edbbef0623..a6a1137d06db 100644
--- a/lib/bug.c
+++ b/lib/bug.c
@@ -47,7 +47,7 @@
 #include <linux/sched.h>
 #include <linux/rculist.h>
 
-extern const struct bug_entry __start___bug_table[], __stop___bug_table[];
+extern struct bug_entry __start___bug_table[], __stop___bug_table[];
 
 static inline unsigned long bug_addr(const struct bug_entry *bug)
 {
@@ -62,10 +62,10 @@ static inline unsigned long bug_addr(const struct bug_entry *bug)
 /* Updates are protected by module mutex */
 static LIST_HEAD(module_bug_list);
 
-static const struct bug_entry *module_find_bug(unsigned long bugaddr)
+static struct bug_entry *module_find_bug(unsigned long bugaddr)
 {
         struct module *mod;
-        const struct bug_entry *bug = NULL;
+        struct bug_entry *bug = NULL;
 
         rcu_read_lock_sched();
         list_for_each_entry_rcu(mod, &module_bug_list, bug_list) {
@@ -122,15 +122,15 @@ void module_bug_cleanup(struct module *mod)
 
 #else
 
-static inline const struct bug_entry *module_find_bug(unsigned long bugaddr)
+static inline struct bug_entry *module_find_bug(unsigned long bugaddr)
 {
         return NULL;
 }
 #endif
 
-const struct bug_entry *find_bug(unsigned long bugaddr)
+struct bug_entry *find_bug(unsigned long bugaddr)
 {
-        const struct bug_entry *bug;
+        struct bug_entry *bug;
 
         for (bug = __start___bug_table; bug < __stop___bug_table; ++bug)
                 if (bugaddr == bug_addr(bug))
@@ -141,9 +141,9 @@ const struct bug_entry *find_bug(unsigned long bugaddr)
 
 enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs)
 {
-        const struct bug_entry *bug;
+        struct bug_entry *bug;
         const char *file;
-        unsigned line, warning;
+        unsigned line, warning, once, done;
 
         if (!is_valid_bugaddr(bugaddr))
                 return BUG_TRAP_TYPE_NONE;
@@ -164,6 +164,18 @@ enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs)
                 line = bug->line;
 #endif
                 warning = (bug->flags & BUGFLAG_WARNING) != 0;
+                once = (bug->flags & BUGFLAG_ONCE) != 0;
+                done = (bug->flags & BUGFLAG_DONE) != 0;
+
+                if (warning && once) {
+                        if (done)
+                                return BUG_TRAP_TYPE_WARN;
+
+                        /*
+                         * Since this is the only store, concurrency is not an issue.
+                         */
+                        bug->flags |= BUGFLAG_DONE;
+                }
         }
 
         if (warning) {