From dc82e52492f684dcd5ed9e4773e72dbf2203d75e Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 15 May 2018 20:25:29 +0200 Subject: ALSA: core: Assure control device to be registered at last The commit 289ca025ee1d ("ALSA: Use priority list for managing device list") changed the way to register/disconnect/free devices via a single priority list. This helped to make behavior consistent, but it also changed a slight behavior change: namely, the control device is registered earlier than others, while it was supposed to be the very last one. I've put SNDRV_DEV_CONTROL in the current position as the release of ctl elements often conflict with the private ctl elements some PCM or other components may create, which often leads to a double-free. But, the order of register and disconnect should be indeed fixed as expected in the early days: the control device gets registered at last, and disconnected at first. This patch changes the priority list order to move SNDRV_DEV_CONTROL as the last guy to assure the register / disconnect order. Meanwhile, for keeping the messy resource release order, manually treat the control and lowlevel devices as last freed one. Additional note: The lowlevel device is the device where a card driver creates at probe. And, we still keep the release order control -> lowlevel, as there might be link from a control element back to a lowlevel object. Fixes: 289ca025ee1d ("ALSA: Use priority list for managing device list") Reported-by: Tzung-Bi Shih Tested-by: Tzung-Bi Shih Signed-off-by: Takashi Iwai --- include/sound/core.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/sound/core.h b/include/sound/core.h index 5f181b875c2f..36a5934cf4b1 100644 --- a/include/sound/core.h +++ b/include/sound/core.h @@ -51,7 +51,6 @@ struct completion; */ enum snd_device_type { SNDRV_DEV_LOWLEVEL, - SNDRV_DEV_CONTROL, SNDRV_DEV_INFO, SNDRV_DEV_BUS, SNDRV_DEV_CODEC, @@ -62,6 +61,7 @@ enum snd_device_type { SNDRV_DEV_SEQUENCER, SNDRV_DEV_HWDEP, SNDRV_DEV_JACK, + SNDRV_DEV_CONTROL, /* NOTE: this must be the last one */ }; enum snd_device_state { -- cgit v1.2.3-59-g8ed1b