module_arch_freeing_init(): new hook for archs before module->module_init freed.

Archs have been abusing module_free() to clean up their arch-specific
allocations.  Since module_free() is also (ab)used by BPF and trace code,
let's keep it to simple allocations, and provide a hook called before
that.

This means that avr32, ia64, parisc and s390 no longer need to implement
their own module_free() at all.  avr32 doesn't need module_finalize()
either.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-s390@vger.kernel.org

1 files changed, 7 insertions, 0 deletions

diff --git a/kernel/module.c b/kernel/module.c
index 3965511ae133..68be0b1f9e7f 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1804,6 +1804,10 @@ void __weak module_arch_cleanup(struct module *mod)
 {
 }
 
+void __weak module_arch_freeing_init(struct module *mod)
+{
+}
+
 /* Free a module, remove from lists, etc. */
 static void free_module(struct module *mod)
 {
@@ -1841,6 +1845,7 @@ static void free_module(struct module *mod)
 
         /* This may be NULL, but that's OK */
         unset_module_init_ro_nx(mod);
+        module_arch_freeing_init(mod);
         module_free(mod, mod->module_init);
         kfree(mod->args);
         percpu_modfree(mod);
@@ -2930,6 +2935,7 @@ static struct module *layout_and_allocate(struct load_info *info, int flags)
 static void module_deallocate(struct module *mod, struct load_info *info)
 {
         percpu_modfree(mod);
+        module_arch_freeing_init(mod);
         module_free(mod, mod->module_init);
         module_free(mod, mod->module_core);
 }
@@ -3055,6 +3061,7 @@ static int do_init_module(struct module *mod)
         mod->strtab = mod->core_strtab;
 #endif
         unset_module_init_ro_nx(mod);
+        module_arch_freeing_init(mod);
         module_free(mod, mod->module_init);
         mod->module_init = NULL;
         mod->init_size = 0;