diff options
| author | Yehuda Sadeh <yehuda@hq.newdream.net> | 2010-07-03 13:07:35 +1000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-07-04 20:17:22 -0700 |
| commit | ff49d74ad383f54041378144ca1a229ee9aeaa59 (patch) | |
| tree | 6f37335e313c9a680db8d4e4ce00d17aa11a099b | |
| parent | e3668dd83ba5958429984286efbc3055be5344c4 (diff) | |
module: initialize module dynamic debug later
We should initialize the module dynamic debug datastructures
only after determining that the module is not loaded yet. This
fixes a bug that introduced in 2.6.35-rc2, where when a trying
to load a module twice, we also load it's dynamic printing data
twice which causes all sorts of nasty issues. Also handle
the dynamic debug cleanup later on failure.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (removed a #ifdef)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/dynamic_debug.h | 4 | ||||
| -rw-r--r-- | kernel/module.c | 23 | ||||
| -rw-r--r-- | lib/dynamic_debug.c | 2 |
3 files changed, 18 insertions, 11 deletions
diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index b3cd4de9432..52c0da4bdd1 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -40,7 +40,7 @@ int ddebug_add_module(struct _ddebug *tab, unsigned int n, const char *modname); #if defined(CONFIG_DYNAMIC_DEBUG) -extern int ddebug_remove_module(char *mod_name); +extern int ddebug_remove_module(const char *mod_name); #define __dynamic_dbg_enabled(dd) ({ \ int __ret = 0; \ @@ -73,7 +73,7 @@ extern int ddebug_remove_module(char *mod_name); #else -static inline int ddebug_remove_module(char *mod) +static inline int ddebug_remove_module(const char *mod) { return 0; } diff --git a/kernel/module.c b/kernel/module.c index 8c6b42840dd..5d2d28197c8 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2062,6 +2062,12 @@ static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num) #endif } +static void dynamic_debug_remove(struct _ddebug *debug) +{ + if (debug) + ddebug_remove_module(debug->modname); +} + static void *module_alloc_update_bounds(unsigned long size) { void *ret = module_alloc(size); @@ -2124,6 +2130,8 @@ static noinline struct module *load_module(void __user *umod, void *ptr = NULL; /* Stops spurious gcc warning */ unsigned long symoffs, stroffs, *strmap; void __percpu *percpu; + struct _ddebug *debug = NULL; + unsigned int num_debug = 0; mm_segment_t old_fs; @@ -2476,15 +2484,9 @@ static noinline struct module *load_module(void __user *umod, kfree(strmap); strmap = NULL; - if (!mod->taints) { - struct _ddebug *debug; - unsigned int num_debug; - + if (!mod->taints) debug = section_objs(hdr, sechdrs, secstrings, "__verbose", sizeof(*debug), &num_debug); - if (debug) - dynamic_debug_setup(debug, num_debug); - } err = module_finalize(hdr, sechdrs, mod); if (err < 0) @@ -2526,10 +2528,13 @@ static noinline struct module *load_module(void __user *umod, goto unlock; } + if (debug) + dynamic_debug_setup(debug, num_debug); + /* Find duplicate symbols */ err = verify_export_symbols(mod); if (err < 0) - goto unlock; + goto ddebug; list_add_rcu(&mod->list, &modules); mutex_unlock(&module_mutex); @@ -2557,6 +2562,8 @@ static noinline struct module *load_module(void __user *umod, mutex_lock(&module_mutex); /* Unlink carefully: kallsyms could be walking list. */ list_del_rcu(&mod->list); + ddebug: + dynamic_debug_remove(debug); unlock: mutex_unlock(&module_mutex); synchronize_sched(); diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 3df8eb17a60..02afc253372 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -692,7 +692,7 @@ static void ddebug_table_free(struct ddebug_table *dt) * Called in response to a module being unloaded. Removes * any ddebug_table's which point at the module. */ -int ddebug_remove_module(char *mod_name) +int ddebug_remove_module(const char *mod_name) { struct ddebug_table *dt, *nextdt; int ret = -ENOENT; |