sysfs: kill unnecessary attribute->owner

sysfs is now completely out of driver/module lifetime game.  After
deletion, a sysfs node doesn't access anything outside sysfs proper,
so there's no reason to hold onto the attribute owners.  Note that
often the wrong modules were accounted for as owners leading to
accessing removed modules.

This patch kills now unnecessary attribute->owner.  Note that with
this change, userland holding a sysfs node does not prevent the
backing module from being unloaded.

For more info regarding lifetime rule cleanup, please read the
following message.

  http://article.gmane.org/gmane.linux.kernel/510293

(tweaked by Greg to not delete the field just yet, to make it easier to
merge things properly.)

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 3 insertions, 7 deletions

diff --git a/kernel/module.c b/kernel/module.c
index 9bd93de01f4a..015d60cfd90e 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -488,8 +488,7 @@ static void free_modinfo_##field(struct module *mod)                  \
         mod->field = NULL;                                            \
 }                                                                     \
 static struct module_attribute modinfo_##field = {                    \
-        .attr = { .name = __stringify(field), .mode = 0444,           \
-                  .owner = THIS_MODULE },                             \
+        .attr = { .name = __stringify(field), .mode = 0444 },         \
         .show = show_modinfo_##field,                                 \
         .setup = setup_modinfo_##field,                               \
         .test = modinfo_##field##_exists,                             \
@@ -793,7 +792,7 @@ static ssize_t show_refcnt(struct module_attribute *mattr,
 }
 
 static struct module_attribute refcnt = {
-        .attr = { .name = "refcnt", .mode = 0444, .owner = THIS_MODULE },
+        .attr = { .name = "refcnt", .mode = 0444 },
         .show = show_refcnt,
 };
 
@@ -851,7 +850,7 @@ static ssize_t show_initstate(struct module_attribute *mattr,
 }
 
 static struct module_attribute initstate = {
-        .attr = { .name = "initstate", .mode = 0444, .owner = THIS_MODULE },
+        .attr = { .name = "initstate", .mode = 0444 },
         .show = show_initstate,
 };
 
@@ -1032,7 +1031,6 @@ static void add_sect_attrs(struct module *mod, unsigned int nsect,
                 sattr->mattr.show = module_sect_show;
                 sattr->mattr.store = NULL;
                 sattr->mattr.attr.name = sattr->name;
-                sattr->mattr.attr.owner = mod;
                 sattr->mattr.attr.mode = S_IRUGO;
                 *(gattr++) = &(sattr++)->mattr.attr;
         }
@@ -1090,7 +1088,6 @@ int module_add_modinfo_attrs(struct module *mod)
                 if (!attr->test ||
                     (attr->test && attr->test(mod))) {
                         memcpy(temp_attr, attr, sizeof(*temp_attr));
-                        temp_attr->attr.owner = mod;
                         error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
                         ++temp_attr;
                 }
diff --git a/kernel/params.c b/kernel/params.c
index e61c46c97ce7..effbaaedd7f3 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -491,7 +491,6 @@ param_sysfs_setup(struct module_kobject *mk,
                         pattr->mattr.show = param_attr_show;
                         pattr->mattr.store = param_attr_store;
                         pattr->mattr.attr.name = (char *)&kp->name[name_skip];
-                        pattr->mattr.attr.owner = mk->mod;
                         pattr->mattr.attr.mode = kp->perm;
                         *(gattr++) = &(pattr++)->mattr.attr;
                 }