From: Jeff Mahoney <jeffm@suse.com>
Subject: Export supported status via sysfs

 This patch adds a /sys/kernel/supported file indicating the supportability
 status of the entire kernel.

 It also adds a /sys/module/<module>/supported file indicating the
 supportability status of individual modules.

 This is useful because it can be used to obtain the supported status
 of a running system without current modules (ie: immediately after
 a kernel update but before a reboot) and without generating an oops.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>

---

 include/linux/module.h |    1 
 kernel/ksysfs.c        |   18 ++++++++++++
 kernel/module.c        |   70 ++++++++++++++++++++++++++++++++-----------------
 3 files changed, 66 insertions(+), 23 deletions(-)

--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -363,6 +363,7 @@ static inline int module_is_live(struct 
 struct module *module_text_address(unsigned long addr);
 struct module *__module_text_address(unsigned long addr);
 int is_module_address(unsigned long addr);
+const char *supported_printable(int taint);
 
 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
    symnum out of range. */
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -104,6 +104,23 @@ static struct bin_attribute notes_attr =
 struct kobject *kernel_kobj;
 EXPORT_SYMBOL_GPL(kernel_kobj);
 
+const char *supported_printable(int taint)
+{
+	if (taint & TAINT_NO_SUPPORT)
+		return "No";
+	else if (taint & TAINT_EXTERNAL_SUPPORT)
+		return "Yes, External";
+	else
+		return "Yes";
+}
+
+static ssize_t supported_show(struct kobject *kobj,
+			      struct kobj_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%s\n", supported_printable(tainted));
+}
+KERNEL_ATTR_RO(supported);
+
 static struct attribute * kernel_attrs[] = {
 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 	&uevent_seqnum_attr.attr,
@@ -114,6 +131,7 @@ static struct attribute * kernel_attrs[]
 	&kexec_crash_loaded_attr.attr,
 	&vmcoreinfo_attr.attr,
 #endif
+	&supported_attr.attr,
 	NULL
 };
 
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -922,10 +922,36 @@ static struct module_attribute initstate
 	.show = show_initstate,
 };
 
+static void setup_modinfo_supported(struct module *mod, const char *s)
+{
+	if (!s) {
+		mod->taints |= TAINT_NO_SUPPORT;
+		return;
+	}
+
+	if (strcmp(s, "external") == 0)
+		mod->taints |= TAINT_EXTERNAL_SUPPORT;
+	else if (strcmp(s, "yes"))
+		mod->taints |= TAINT_NO_SUPPORT;
+}
+
+static ssize_t show_modinfo_supported(struct module_attribute *mattr,
+	                struct module *mod, char *buffer)
+{
+	return sprintf(buffer, "%s\n", supported_printable(mod->taints));
+}
+
+static struct module_attribute modinfo_supported = {
+	.attr = { .name = "supported", .mode = 0444 },
+	.show = show_modinfo_supported,
+	.setup = setup_modinfo_supported,
+};
+
 static struct module_attribute *modinfo_attrs[] = {
 	&modinfo_version,
 	&modinfo_srcversion,
 	&initstate,
+	&modinfo_supported,
 #ifdef CONFIG_MODULE_UNLOAD
 	&refcnt,
 #endif
@@ -1820,7 +1846,6 @@ static noinline struct module *load_modu
 	Elf_Ehdr *hdr;
 	Elf_Shdr *sechdrs;
 	char *secstrings, *args, *modmagic, *strtab = NULL;
-	char *supported;
 	unsigned int i;
 	unsigned int symindex = 0;
 	unsigned int strindex = 0;
@@ -1975,28 +2000,6 @@ static noinline struct module *load_modu
 		goto free_hdr;
 	}
 
-	supported = get_modinfo(sechdrs, infoindex, "supported");
-	if (supported) {
-		if (!strcmp(supported, "external"))
-			add_taint_module(mod, TAINT_EXTERNAL_SUPPORT);
-		else if (strcmp(supported, "yes"))
-			supported = NULL;
-	}
-	if (!supported) {
-		if (unsupported == 0) {
-			printk(KERN_WARNING "%s: module not supported by "
-			       "Novell, refusing to load. To override, echo "
-			       "1 > /proc/sys/kernel/unsupported\n", mod->name);
-			err = -ENOEXEC;
-			goto free_hdr;
-		}
-		add_taint_module(mod, TAINT_NO_SUPPORT);
-		if (unsupported == 1) {
-			printk(KERN_WARNING "%s: module not supported by "
-			       "Novell, setting U taint flag.\n", mod->name);
-		}
-	}
-
 	/* Now copy in args */
 	args = strndup_user(uargs, ~0UL >> 1);
 	if (IS_ERR(args)) {
@@ -2256,6 +2259,26 @@ static noinline struct module *load_modu
 	add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
 	add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
 
+	/* We don't use add_taint() here because it also disables lockdep. */
+	if (mod->taints & TAINT_EXTERNAL_SUPPORT)
+		tainted |= TAINT_EXTERNAL_SUPPORT;
+	else if (mod->taints == TAINT_NO_SUPPORT) {
+		if (unsupported == 0) {
+			printk(KERN_WARNING "%s: module not supported by "
+			       "Novell, refusing to load. To override, echo "
+			       "1 > /proc/sys/kernel/unsupported\n", mod->name);
+			err = -ENOEXEC;
+			goto free_hdr;
+		}
+		tainted |= TAINT_NO_SUPPORT;
+		if (unsupported == 1) {
+			printk(KERN_WARNING "%s: module is not supported by "
+			       "Novell. Novell Technical Services may decline "
+			       "your support request if it involves a kernel "
+			       "fault.\n", mod->name);
+		}
+	}
+
 	/* Size of section 0 is 0, so this works well if no unwind info. */
 	mod->unwind_info = unwind_add_table(mod,
 					    (void *)sechdrs[unwindex].sh_addr,
@@ -2735,6 +2758,7 @@ void print_modules(void)
 	if (last_unloaded_module[0])
 		printk(" [last unloaded: %s]", last_unloaded_module);
 	printk("\n");
+	printk("Supported: %s\n", supported_printable(tainted));
 }
 
 #ifdef CONFIG_MODVERSIONS