[PATCH] add EXPORT_SYMBOL_GPL_FUTURE()

This patch adds the ability to mark symbols that will be changed in the
future, so that kernel modules that don't include MODULE_LICENSE("GPL")
and use the symbols, will be flagged and printed out to the system log.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 23 insertions, 0 deletions

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 35de20cf8fac..9d11550b4818 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -58,6 +58,13 @@
                 VMLINUX_SYMBOL(__stop___ksymtab_gpl) = .;               \
         }                                                               \
                                                                         \
+        /* Kernel symbol table: GPL-future-only symbols */              \
+        __ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \
+                VMLINUX_SYMBOL(__start___ksymtab_gpl_future) = .;       \
+                *(__ksymtab_gpl_future)                                 \
+                VMLINUX_SYMBOL(__stop___ksymtab_gpl_future) = .;        \
+        }                                                               \
+                                                                        \
         /* Kernel symbol table: Normal symbols */                       \
         __kcrctab         : AT(ADDR(__kcrctab) - LOAD_OFFSET) {         \
                 VMLINUX_SYMBOL(__start___kcrctab) = .;                  \
@@ -72,6 +79,13 @@
                 VMLINUX_SYMBOL(__stop___kcrctab_gpl) = .;               \
         }                                                               \
                                                                         \
+        /* Kernel symbol table: GPL-future-only symbols */              \
+        __kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \
+                VMLINUX_SYMBOL(__start___kcrctab_gpl_future) = .;       \
+                *(__kcrctab_gpl_future)                                 \
+                VMLINUX_SYMBOL(__stop___kcrctab_gpl_future) = .;        \
+        }                                                               \
+                                                                        \
         /* Kernel symbol table: strings */                              \
         __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \
                 *(__ksymtab_strings)                                    \
diff --git a/include/linux/module.h b/include/linux/module.h
index 84d75f3a8aca..a25d5f61548c 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -198,6 +198,9 @@ void *__symbol_get_gpl(const char *symbol);
 #define EXPORT_SYMBOL_GPL(sym)                                  \
         __EXPORT_SYMBOL(sym, "_gpl")
 
+#define EXPORT_SYMBOL_GPL_FUTURE(sym)                           \
+        __EXPORT_SYMBOL(sym, "_gpl_future")
+
 #endif
 
 struct module_ref
@@ -255,6 +258,11 @@ struct module
         unsigned int num_gpl_syms;
         const unsigned long *gpl_crcs;
 
+        /* symbols that will be GPL-only in the near future. */
+        const struct kernel_symbol *gpl_future_syms;
+        unsigned int num_gpl_future_syms;
+        const unsigned long *gpl_future_crcs;
+
         /* Exception table */
         unsigned int num_exentries;
         const struct exception_table_entry *extable;
@@ -441,6 +449,7 @@ void module_remove_driver(struct device_driver *);
 #else /* !CONFIG_MODULES... */
 #define EXPORT_SYMBOL(sym)
 #define EXPORT_SYMBOL_GPL(sym)
+#define EXPORT_SYMBOL_GPL_FUTURE(sym)
 
 /* Given an address, look for it in the exception tables. */
 static inline const struct exception_table_entry *