OpenWrt – Rev 1
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From: Rusty Russell <rusty@rustcorp.com.au>
Date: Tue, 20 Jan 2015 09:07:04 +1030
Subject: [PATCH] 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
Origin: backport, https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d453cded05ee219b77815ea194dc36efa5398bca
---
arch/avr32/kernel/module.c | 13 +------------
arch/ia64/kernel/module.c | 6 ++----
arch/parisc/kernel/module.c | 6 +-----
arch/s390/kernel/module.c | 10 +++-------
arch/tile/kernel/module.c | 2 +-
include/linux/moduleloader.h | 2 ++
kernel/module.c | 7 +++++++
7 files changed, 17 insertions(+), 29 deletions(-)
--- a/arch/avr32/kernel/module.c
+++ b/arch/avr32/kernel/module.c
@@ -19,12 +19,10 @@
#include <linux/moduleloader.h>
#include <linux/vmalloc.h>
-void module_free(struct module *mod, void *module_region)
+void module_arch_freeing_init(struct module *mod)
{
vfree(mod->arch.syminfo);
mod->arch.syminfo = NULL;
-
- vfree(module_region);
}
static inline int check_rela(Elf32_Rela *rela, struct module *module,
@@ -291,12 +289,3 @@ int apply_relocate_add(Elf32_Shdr *sechd
return ret;
}
-
-int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
- struct module *module)
-{
- vfree(module->arch.syminfo);
- module->arch.syminfo = NULL;
-
- return 0;
-}
--- a/arch/ia64/kernel/module.c
+++ b/arch/ia64/kernel/module.c
@@ -305,14 +305,12 @@ plt_target (struct plt_entry *plt)
#endif /* !USE_BRL */
void
-module_free (struct module *mod, void *module_region)
+module_arch_freeing_init (struct module *mod)
{
- if (mod && mod->arch.init_unw_table &&
- module_region == mod->module_init) {
+ if (mod->arch.init_unw_table) {
unw_remove_unwind_table(mod->arch.init_unw_table);
mod->arch.init_unw_table = NULL;
}
- vfree(module_region);
}
/* Have we already seen one of these relocations? */
--- a/arch/parisc/kernel/module.c
+++ b/arch/parisc/kernel/module.c
@@ -298,14 +298,10 @@ static inline unsigned long count_stubs(
}
#endif
-
-/* Free memory returned from module_alloc */
-void module_free(struct module *mod, void *module_region)
+void module_arch_freeing_init(struct module *mod)
{
kfree(mod->arch.section);
mod->arch.section = NULL;
-
- vfree(module_region);
}
/* Additional bytes needed in front of individual sections */
--- a/arch/s390/kernel/module.c
+++ b/arch/s390/kernel/module.c
@@ -55,14 +55,10 @@ void *module_alloc(unsigned long size)
}
#endif
-/* Free memory returned from module_alloc */
-void module_free(struct module *mod, void *module_region)
+void module_arch_freeing_init(struct module *mod)
{
- if (mod) {
- vfree(mod->arch.syminfo);
- mod->arch.syminfo = NULL;
- }
- vfree(module_region);
+ vfree(mod->arch.syminfo);
+ mod->arch.syminfo = NULL;
}
static void check_rela(Elf_Rela *rela, struct module *me)
--- a/arch/tile/kernel/module.c
+++ b/arch/tile/kernel/module.c
@@ -83,7 +83,7 @@ void module_free(struct module *mod, voi
0, 0, 0, NULL, NULL, 0);
/*
- * FIXME: If module_region == mod->module_init, trim exception
+ * FIXME: Add module_arch_freeing_init to trim exception
* table entries.
*/
}
--- a/include/linux/moduleloader.h
+++ b/include/linux/moduleloader.h
@@ -82,4 +82,6 @@ int module_finalize(const Elf_Ehdr *hdr,
/* Any cleanup needed when module leaves. */
void module_arch_cleanup(struct module *mod);
+/* Any cleanup before freeing mod->module_init */
+void module_arch_freeing_init(struct module *mod);
#endif
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1840,6 +1840,10 @@ void __weak module_arch_cleanup(struct m
{
}
+void __weak module_arch_freeing_init(struct module *mod)
+{
+}
+
/* Free a module, remove from lists, etc. */
static void free_module(struct module *mod)
{
@@ -1872,6 +1876,7 @@ static void free_module(struct module *m
/* 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);
@@ -2983,6 +2988,7 @@ static struct module *layout_and_allocat
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);
}
@@ -3105,6 +3111,7 @@ static int do_init_module(struct module
rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms);
#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;