module/retpoline: Warn about missing retpoline in module

[pandora-kernel.git] / scripts / mod / modpost.c

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 2bd594e..cd23f82 100644 (file)
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -28,9 +28,9 @@
 
 
 /* Are we using CONFIG_MODVERSIONS? */
-int modversions = 0;
+static int modversions = 0;
 /* Warn about undefined symbols? (do so if we have vmlinux) */
-int have_vmlinux = 0;
+static int have_vmlinux = 0;
 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */
 static int all_versions = 0;
 /* If we are modposting external module set to 1 */
@@ -132,8 +132,10 @@ static struct module *new_module(char *modname)
        /* strip trailing .o */
        s = strrchr(p, '.');
        if (s != NULL)
-               if (strcmp(s, ".o") == 0)
+               if (strcmp(s, ".o") == 0) {
                        *s = '\0';
+                       mod->is_dot_o = 1;
+               }
 
        /* add to list */
        mod->name = p;
@@ -223,7 +225,7 @@ static struct symbol *find_symbol(const char *name)
        return NULL;
 }
 
-static struct {
+static const struct {
        const char *str;
        enum export export;
 } export_list[] = {
@@ -567,12 +569,16 @@ static int ignore_undef_symbol(struct elf_info *info, const char *symname)
                if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 ||
                    strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 ||
                    strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
-                   strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0)
+                   strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0 ||
+                   strncmp(symname, "_restvr_", sizeof("_restvr_") - 1) == 0 ||
+                   strncmp(symname, "_savevr_", sizeof("_savevr_") - 1) == 0)
                        return 1;
        if (info->hdr->e_machine == EM_PPC64)
                /* Special register function linked on all modules during final link of .ko */
                if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 ||
-                   strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0)
+                   strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0 ||
+                   strncmp(symname, "_restvr_", sizeof("_restvr_") - 1) == 0 ||
+                   strncmp(symname, "_savevr_", sizeof("_savevr_") - 1) == 0)
                        return 1;
        /* Do not ignore this symbol */
        return 0;
@@ -587,7 +593,8 @@ static void handle_modversions(struct module *mod, struct elf_info *info,
        unsigned int crc;
        enum export export;
 
-       if (!is_vmlinux(mod->name) && strncmp(symname, "__ksymtab", 9) == 0)
+       if ((!is_vmlinux(mod->name) || mod->is_dot_o) &&
+           strncmp(symname, "__ksymtab", 9) == 0)
                export = export_from_secname(info, get_secindex(info, sym));
        else
                export = export_from_sec(info, get_secindex(info, sym));
@@ -809,7 +816,7 @@ static int match(const char *sym, const char * const pat[])
 }
 
 /* sections that we do not want to do full section mismatch check on */
-static const char *section_white_list[] =
+static const char *const section_white_list[] =
 {
        ".comment*",
        ".debug*",
@@ -849,7 +856,7 @@ static void check_section(const char *modname, struct elf_info *elf,
 
 #define ALL_INIT_DATA_SECTIONS \
        ".init.setup$", ".init.rodata$", \
-       ".devinit.rodata$", ".cpuinit.rodata$", ".meminit.rodata$" \
+       ".devinit.rodata$", ".cpuinit.rodata$", ".meminit.rodata$", \
        ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$"
 #define ALL_EXIT_DATA_SECTIONS \
        ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$"
@@ -869,6 +876,8 @@ static void check_section(const char *modname, struct elf_info *elf,
 
 #define DATA_SECTIONS ".data$", ".data.rel$"
 #define TEXT_SECTIONS ".text$"
+#define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \
+               ".fixup", ".entry.text"
 
 #define INIT_SECTIONS      ".init.*"
 #define DEV_INIT_SECTIONS  ".devinit.*"
@@ -880,18 +889,25 @@ static void check_section(const char *modname, struct elf_info *elf,
 #define CPU_EXIT_SECTIONS  ".cpuexit.*"
 #define MEM_EXIT_SECTIONS  ".memexit.*"
 
+#define ALL_TEXT_SECTIONS  ALL_INIT_TEXT_SECTIONS, ALL_EXIT_TEXT_SECTIONS, \
+               TEXT_SECTIONS, OTHER_TEXT_SECTIONS
+
 /* init data sections */
-static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL };
+static const char *const init_data_sections[] =
+       { ALL_INIT_DATA_SECTIONS, NULL };
 
 /* all init sections */
-static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL };
+static const char *const init_sections[] = { ALL_INIT_SECTIONS, NULL };
 
 /* All init and exit sections (code + data) */
-static const char *init_exit_sections[] =
+static const char *const init_exit_sections[] =
        {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
 
+/* all text sections */
+static const char *const text_sections[] = { ALL_TEXT_SECTIONS, NULL };
+
 /* data section */
-static const char *data_sections[] = { DATA_SECTIONS, NULL };
+static const char *const data_sections[] = { DATA_SECTIONS, NULL };
 
 
 /* symbols in .data that may refer to init/exit sections */
@@ -905,9 +921,10 @@ static const char *data_sections[] = { DATA_SECTIONS, NULL };
        "*_probe_one",                                                  \
        "*_console"
 
-static const char *head_sections[] = { ".head.text*", NULL };
-static const char *linker_symbols[] =
+static const char *const head_sections[] = { ".head.text*", NULL };
+static const char *const linker_symbols[] =
        { "__init_begin", "_sinittext", "_einittext", NULL };
+static const char *const optim_symbols[] = { "*.constprop.*", NULL };
 
 enum mismatch {
        TEXT_TO_ANY_INIT,
@@ -928,7 +945,7 @@ struct sectioncheck {
        const char *symbol_white_list[20];
 };
 
-const struct sectioncheck sectioncheck[] = {
+static const struct sectioncheck sectioncheck[] = {
 /* Do not reference init/exit code/data from
  * normal code and data
  */
@@ -1089,6 +1106,17 @@ static const struct sectioncheck *section_mismatch(
  *   This pattern is identified by
  *   refsymname = __init_begin, _sinittext, _einittext
  *
+ * Pattern 5:
+ *   GCC may optimize static inlines when fed constant arg(s) resulting
+ *   in functions like cpumask_empty() -- generating an associated symbol
+ *   cpumask_empty.constprop.3 that appears in the audit.  If the const that
+ *   is passed in comes from __init, like say nmi_ipi_mask, we get a
+ *   meaningless section warning.  May need to add isra symbols too...
+ *   This pattern is identified by
+ *   tosec   = init section
+ *   fromsec = text section
+ *   refsymname = *.constprop.*
+ *
  **/
 static int secref_whitelist(const struct sectioncheck *mismatch,
                            const char *fromsec, const char *fromsym,
@@ -1121,6 +1149,12 @@ static int secref_whitelist(const struct sectioncheck *mismatch,
        if (match(tosym, linker_symbols))
                return 0;
 
+       /* Check for pattern 5 */
+       if (match(fromsec, text_sections) &&
+           match(tosec, init_sections) &&
+           match(fromsym, optim_symbols))
+               return 0;
+
        return 1;
 }
 
@@ -1855,6 +1889,14 @@ static void add_intree_flag(struct buffer *b, int is_intree)
                buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
 }
 
+/* Cannot check for assembler */
+static void add_retpoline(struct buffer *b)
+{
+       buf_printf(b, "\n#ifdef RETPOLINE\n");
+       buf_printf(b, "MODULE_INFO(retpoline, \"Y\");\n");
+       buf_printf(b, "#endif\n");
+}
+
 static void add_staging_flag(struct buffer *b, const char *name)
 {
        static const char *staging_dir = "drivers/staging";
@@ -2176,6 +2218,7 @@ int main(int argc, char **argv)
 
                add_header(&buf, mod);
                add_intree_flag(&buf, !external_module);
+               add_retpoline(&buf);
                add_staging_flag(&buf, mod->name);
                err |= add_versions(&buf, mod);
                add_depends(&buf, mod, modules);