On Fri, 10 May 2019 14:21:41 +0200, Amadeusz Sławiński wrote: > > hda_widget_sysfs_reinit() can free underlying codec->widgets structure > on which widget_tree_create() operates. Add locking to prevent such > issues from happening. > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=110382 > Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@xxxxxxxxxxxxxxx> Thanks, the idea looks good. But it'd be simpler to do mutex lock/unlock in the caller side, a patch like below. Takashi --- a/include/sound/hdaudio.h +++ b/include/sound/hdaudio.h @@ -81,6 +81,7 @@ struct hdac_device { atomic_t in_pm; /* suspend/resume being performed */ /* sysfs */ + struct mutex widget_lock; struct hdac_widget_tree *widgets; /* regmap */ --- a/sound/hda/hdac_device.c +++ b/sound/hda/hdac_device.c @@ -55,6 +55,7 @@ int snd_hdac_device_init(struct hdac_device *codec, struct hdac_bus *bus, codec->bus = bus; codec->addr = addr; codec->type = HDA_DEV_CORE; + mutex_init(&codec->widget_lock); pm_runtime_set_active(&codec->dev); pm_runtime_get_noresume(&codec->dev); atomic_set(&codec->in_pm, 0); @@ -141,7 +142,9 @@ int snd_hdac_device_register(struct hdac_device *codec) err = device_add(&codec->dev); if (err < 0) return err; + mutex_lock(&codec->widget_lock); err = hda_widget_sysfs_init(codec); + mutex_unlock(&codec->widget_lock); if (err < 0) { device_del(&codec->dev); return err; @@ -158,7 +161,9 @@ EXPORT_SYMBOL_GPL(snd_hdac_device_register); void snd_hdac_device_unregister(struct hdac_device *codec) { if (device_is_registered(&codec->dev)) { + mutex_lock(&codec->widget_lock); hda_widget_sysfs_exit(codec); + mutex_unlock(&codec->widget_lock); device_del(&codec->dev); snd_hdac_bus_remove_device(codec->bus, codec); } @@ -404,7 +409,9 @@ int snd_hdac_refresh_widgets(struct hdac_device *codec, bool sysfs) } if (sysfs) { + mutex_lock(&codec->widget_lock); err = hda_widget_sysfs_reinit(codec, start_nid, nums); + mutex_unlock(&codec->widget_lock); if (err < 0) return err; } _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
