From: Takashi Iwai Date: Fri, 25 Jan 2013 00:28:18 +0000 (+1000) Subject: fb: Yet another band-aid for fixing lockdep mess X-Git-Tag: v3.2.40~116 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=2f6cca22e6302c99d7d7035f762ffce1e83bd7ab;p=thirdparty%2Fkernel%2Fstable.git fb: Yet another band-aid for fixing lockdep mess commit e93a9a868792ad71cdd09d75e5a02d8067473c4e upstream. I've still got lockdep warnings even after Alan's patch, and it seems that yet more band aids are required to paper over similar paths for unbind_con_driver() and unregister_con_driver(). After this hack, lockdep warnings are finally gone. Signed-off-by: Takashi Iwai Cc: Alan Cox Cc: Florian Tobias Schandinat Cc: Jiri Kosina Tested-by: Sedat Dilek Signed-off-by: Andrew Morton Signed-off-by: Dave Airlie Signed-off-by: Ben Hutchings --- diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index e2345d43a3613..632df54fab0f0 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -3163,6 +3163,18 @@ static int con_is_graphics(const struct consw *csw, int first, int last) * or 0 on success. */ int unbind_con_driver(const struct consw *csw, int first, int last, int deflt) +{ + int retval; + + console_lock(); + retval = do_unbind_con_driver(csw, first, last, deflt); + console_unlock(); + return retval; +} +EXPORT_SYMBOL(unbind_con_driver); + +/* unlocked version of unbind_con_driver() */ +int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt) { struct module *owner = csw->owner; const struct consw *defcsw = NULL; @@ -3172,7 +3184,7 @@ int unbind_con_driver(const struct consw *csw, int first, int last, int deflt) if (!try_module_get(owner)) return -ENODEV; - console_lock(); + WARN_CONSOLE_UNLOCKED(); /* check if driver is registered and if it is unbindable */ for (i = 0; i < MAX_NR_CON_DRIVER; i++) { @@ -3185,10 +3197,8 @@ int unbind_con_driver(const struct consw *csw, int first, int last, int deflt) } } - if (retval) { - console_unlock(); + if (retval) goto err; - } retval = -ENODEV; @@ -3204,15 +3214,11 @@ int unbind_con_driver(const struct consw *csw, int first, int last, int deflt) } } - if (retval) { - console_unlock(); + if (retval) goto err; - } - if (!con_is_bound(csw)) { - console_unlock(); + if (!con_is_bound(csw)) goto err; - } first = max(first, con_driver->first); last = min(last, con_driver->last); @@ -3241,13 +3247,12 @@ int unbind_con_driver(const struct consw *csw, int first, int last, int deflt) /* ignore return value, binding should not fail */ do_bind_con_driver(defcsw, first, last, deflt); - console_unlock(); err: module_put(owner); return retval; } -EXPORT_SYMBOL(unbind_con_driver); +EXPORT_SYMBOL_GPL(do_unbind_con_driver); static int vt_bind(struct con_driver *con) { @@ -3621,9 +3626,18 @@ EXPORT_SYMBOL(register_con_driver); */ int unregister_con_driver(const struct consw *csw) { - int i, retval = -ENODEV; + int retval; console_lock(); + retval = do_unregister_con_driver(csw); + console_unlock(); + return retval; +} +EXPORT_SYMBOL(unregister_con_driver); + +int do_unregister_con_driver(const struct consw *csw) +{ + int i, retval = -ENODEV; /* cannot unregister a bound driver */ if (con_is_bound(csw)) @@ -3649,10 +3663,9 @@ int unregister_con_driver(const struct consw *csw) } } err: - console_unlock(); return retval; } -EXPORT_SYMBOL(unregister_con_driver); +EXPORT_SYMBOL_GPL(do_unregister_con_driver); /* * If we support more console drivers, this function is used diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c index 18d02c6af70c5..9b8bcab0ae32e 100644 --- a/drivers/video/console/fbcon.c +++ b/drivers/video/console/fbcon.c @@ -3011,7 +3011,7 @@ static int fbcon_unbind(void) { int ret; - ret = unbind_con_driver(&fb_con, first_fb_vc, last_fb_vc, + ret = do_unbind_con_driver(&fb_con, first_fb_vc, last_fb_vc, fbcon_is_default); if (!ret) @@ -3084,7 +3084,7 @@ static int fbcon_fb_unregistered(struct fb_info *info) primary_device = -1; if (!num_registered_fb) - unregister_con_driver(&fb_con); + do_unregister_con_driver(&fb_con); return 0; } diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c index a94edc3f58b0f..c133dde79cd37 100644 --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -1646,8 +1646,10 @@ static int do_unregister_framebuffer(struct fb_info *fb_info) if (!lock_fb_info(fb_info)) return -ENODEV; + console_lock(); event.info = fb_info; ret = fb_notifier_call_chain(FB_EVENT_FB_UNBIND, &event); + console_unlock(); unlock_fb_info(fb_info); if (ret) @@ -1662,7 +1664,9 @@ static int do_unregister_framebuffer(struct fb_info *fb_info) num_registered_fb--; fb_cleanup_device(fb_info); event.info = fb_info; + console_lock(); fb_notifier_call_chain(FB_EVENT_FB_UNREGISTERED, &event); + console_unlock(); /* this may free fb info */ put_fb_info(fb_info); diff --git a/include/linux/console.h b/include/linux/console.h index 49b1061f3a0cb..6ae6a15eb95c2 100644 --- a/include/linux/console.h +++ b/include/linux/console.h @@ -77,6 +77,7 @@ extern const struct consw prom_con; /* SPARC PROM console */ int con_is_bound(const struct consw *csw); int register_con_driver(const struct consw *csw, int first, int last); int unregister_con_driver(const struct consw *csw); +int do_unregister_con_driver(const struct consw *csw); int take_over_console(const struct consw *sw, int first, int last, int deflt); int do_take_over_console(const struct consw *sw, int first, int last, int deflt); void give_up_console(const struct consw *sw); diff --git a/include/linux/vt_kern.h b/include/linux/vt_kern.h index 932276d6c9d1d..644921fc39a86 100644 --- a/include/linux/vt_kern.h +++ b/include/linux/vt_kern.h @@ -132,6 +132,8 @@ void vt_event_post(unsigned int event, unsigned int old, unsigned int new); int vt_waitactive(int n); void change_console(struct vc_data *new_vc); void reset_vc(struct vc_data *vc); +extern int do_unbind_con_driver(const struct consw *csw, int first, int last, + int deflt); extern int unbind_con_driver(const struct consw *csw, int first, int last, int deflt); int vty_init(const struct file_operations *console_fops);