Revision ebff65473f56e6c30de928fd6a4f1ce5ae36e8c5 authored by Shawn Guo on 02 December 2013, 05:26:50 UTC, committed by Mark Brown on 02 December 2013, 11:50:53 UTC
Since devm_card_release() expects parameter 'res' to be a pointer to
struct snd_soc_card, devm_snd_soc_register_card() should really pass
such a pointer rather than the one to struct device.

This bug causes the kernel Oops below with imx-sgtl500 driver when we
remove the module.  It happens because with 'card' pointing to the wrong
structure, card->num_rtd becomes 0 in function soc_remove_dai_links().
Consequently, soc_remove_link_components() and in turn
soc_cleanup_codec[platform]_debugfs() will not be called on card
removal.  It results in that debugfs_card_root is being removed while
its child entries debugfs_codec_root and debugfs_platform_root are still
there, and thus the kernel Oops.

Fix the bug by correcting the parameter 'res' to be the pointer to
struct snd_soc_card.

$ lsmod
Module                  Size  Used by
snd_soc_imx_sgtl5000     3506  0
snd_soc_sgtl5000       13677  2
snd_soc_imx_audmux      5324  1 snd_soc_imx_sgtl5000
snd_soc_fsl_ssi         8139  2
imx_pcm_dma             1380  1 snd_soc_fsl_ssi
$ rmmod snd_soc_imx_sgtl5000
Unable to handle kernel paging request at virtual address e594025c
pgd = be134000
[e594025c] *pgd=00000000
Internal error: Oops: 5 [#1] SMP ARM
Modules linked in: snd_soc_imx_sgtl5000(-) snd_soc_sgtl5000 snd_soc_imx_audmux snd_soc_fsl_ssi imx_pcm_dma
CPU: 0 PID: 1793 Comm: rmmod Not tainted 3.13.0-rc1 #1570
task: bee28900 ti: bfbec000 task.ti: bfbec000
PC is at debugfs_remove_recursive+0x28/0x154
LR is at snd_soc_unregister_card+0xa0/0xcc
pc : [<80252b38>]    lr : [<80496ac4>]    psr: a0000013
sp : bfbede00  ip : bfbede28  fp : bfbede24
r10: 803281d4  r9 : bfbec000  r8 : 803271ac
r7 : bef54440  r6 : 00000004  r5 : bf9a4010  r4 : bf9a4010
r3 : e5940224  r2 : 00000000  r1 : bef54450  r0 : 803271ac
Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 10c53c7d  Table: 4e13404a  DAC: 00000015
Process rmmod (pid: 1793, stack limit = 0xbfbec240)
Stack: (0xbfbede00 to 0xbfbee000)
de00: 00000000 bf9a4010 bf9a4010 00000004 bef54440 bec89000 bfbede44 bfbede28
de20: 80496ac4 80252b1c 804a4b60 bfbede60 bf9a4010 00000004 bfbede54 bfbede48
de40: 804a4b74 80496a30 bfbede94 bfbede58 80328728 804a4b6c bfbede94 a0000013
de60: bf1b5800 bef54440 00000002 bf9a4010 7f0169f8 bf9a4044 00000081 8000e9c4
de80: bfbec000 00000000 bfbedeac bfbede98 80328cb0 80328618 7f016000 bf9a4010
dea0: bfbedec4 bfbedeb0 8032561c 80328c84 bf9a4010 7f0169f8 bfbedee4 bfbedec8
dec0: 80325e84 803255a8 bee28900 7f0169f8 00000000 78208d30 bfbedefc bfbedee8
dee0: 80325410 80325dd4 beca8100 7f0169f8 bfbedf14 bfbedf00 803264f8 803253c8
df00: 7f01635c 7f016a3c bfbedf24 bfbedf18 80327098 803264d4 bfbedf34 bfbedf28
df20: 7f016370 80327090 bfbedfa4 bfbedf38 80085ef0 7f016368 bfbedf54 5f646e73
df40: 5f636f73 5f786d69 6c746773 30303035 00000000 78208008 bfbedf84 bfbedf68
df60: 800613b0 80061194 fffffffe 78208d00 7efc2f07 00000081 7f016a3c 00000800
df80: bfbedf84 00000000 00000000 fffffffe 78208d00 7efc2f07 00000000 bfbedfa8
dfa0: 8000e800 80085dcc fffffffe 78208d00 78208d30 00000800 a8c82400 a8c82400
dfc0: fffffffe 78208d00 7efc2f07 00000081 00000002 00000000 78208008 00000800
dfe0: 7efc2e1c 7efc2ba8 76f5ca47 76edec7c 80000010 78208d30 00000000 00000000
Backtrace:
[<80252b10>] (debugfs_remove_recursive+0x0/0x154) from [<80496ac4>] (snd_soc_unregister_card+0xa0/0xcc)
 r8:bec89000 r7:bef54440 r6:00000004 r5:bf9a4010 r4:bf9a4010
r3:00000000
[<80496a24>] (snd_soc_unregister_card+0x0/0xcc) from [<804a4b74>] (devm_card_release+0x14/0x18)
 r6:00000004 r5:bf9a4010 r4:bfbede60 r3:804a4b60
[<804a4b60>] (devm_card_release+0x0/0x18) from [<80328728>] (release_nodes+0x11c/0x1dc)
[<8032860c>] (release_nodes+0x0/0x1dc) from [<80328cb0>] (devres_release_all+0x38/0x54)
[<80328c78>] (devres_release_all+0x0/0x54) from [<8032561c>] (__device_release_driver+0x80/0xd4)
 r4:bf9a4010 r3:7f016000
[<8032559c>] (__device_release_driver+0x0/0xd4) from [<80325e84>] (driver_detach+0xbc/0xc0)
 r5:7f0169f8 r4:bf9a4010
[<80325dc8>] (driver_detach+0x0/0xc0) from [<80325410>] (bus_remove_driver+0x54/0x98)
 r6:78208d30 r5:00000000 r4:7f0169f8 r3:bee28900
[<803253bc>] (bus_remove_driver+0x0/0x98) from [<803264f8>] (driver_unregister+0x30/0x50)
 r4:7f0169f8 r3:beca8100
[<803264c8>] (driver_unregister+0x0/0x50) from [<80327098>] (platform_driver_unregister+0x14/0x18)
 r4:7f016a3c r3:7f01635c
[<80327084>] (platform_driver_unregister+0x0/0x18) from [<7f016370>] (imx_sgtl5000_driver_exit+0x14/0x1c [snd_soc_imx_sgtl5000])
[<7f01635c>] (imx_sgtl5000_driver_exit+0x0/0x1c [snd_soc_imx_sgtl5000]) from [<80085ef0>] (SyS_delete_module+0x130/0x18c)
[<80085dc0>] (SyS_delete_module+0x0/0x18c) from [<8000e800>] (ret_fast_syscall+0x0/0x48)
 r6:7efc2f07 r5:78208d00 r4:fffffffe
Code: 889da9f8 e5983020 e3530000 089da9f8 (e5933038)
---[ end trace 825e7e125251a225 ]---

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
1 parent 8f1ec93
Raw File
info.h
#ifndef __SOUND_INFO_H
#define __SOUND_INFO_H

/*
 *  Header file for info interface
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <linux/poll.h>

/* buffer for information */
struct snd_info_buffer {
	char *buffer;		/* pointer to begin of buffer */
	unsigned int curr;	/* current position in buffer */
	unsigned int size;	/* current size */
	unsigned int len;	/* total length of buffer */
	int stop;		/* stop flag */
	int error;		/* error code */
};

#define SNDRV_INFO_CONTENT_TEXT		0
#define SNDRV_INFO_CONTENT_DATA		1

struct snd_info_entry;

struct snd_info_entry_text {
	void (*read)(struct snd_info_entry *entry,
		     struct snd_info_buffer *buffer);
	void (*write)(struct snd_info_entry *entry,
		      struct snd_info_buffer *buffer);
};

struct snd_info_entry_ops {
	int (*open)(struct snd_info_entry *entry,
		    unsigned short mode, void **file_private_data);
	int (*release)(struct snd_info_entry *entry,
		       unsigned short mode, void *file_private_data);
	ssize_t (*read)(struct snd_info_entry *entry, void *file_private_data,
			struct file *file, char __user *buf,
			size_t count, loff_t pos);
	ssize_t (*write)(struct snd_info_entry *entry, void *file_private_data,
			 struct file *file, const char __user *buf,
			 size_t count, loff_t pos);
	loff_t (*llseek)(struct snd_info_entry *entry,
			 void *file_private_data, struct file *file,
			 loff_t offset, int orig);
	unsigned int (*poll)(struct snd_info_entry *entry,
			     void *file_private_data, struct file *file,
			     poll_table *wait);
	int (*ioctl)(struct snd_info_entry *entry, void *file_private_data,
		     struct file *file, unsigned int cmd, unsigned long arg);
	int (*mmap)(struct snd_info_entry *entry, void *file_private_data,
		    struct inode *inode, struct file *file,
		    struct vm_area_struct *vma);
};

struct snd_info_entry {
	const char *name;
	umode_t mode;
	long size;
	unsigned short content;
	union {
		struct snd_info_entry_text text;
		struct snd_info_entry_ops *ops;
	} c;
	struct snd_info_entry *parent;
	struct snd_card *card;
	struct module *module;
	void *private_data;
	void (*private_free)(struct snd_info_entry *entry);
	struct proc_dir_entry *p;
	struct mutex access;
	struct list_head children;
	struct list_head list;
};

#if defined(CONFIG_SND_OSSEMUL) && defined(CONFIG_PROC_FS)
int snd_info_minor_register(void);
int snd_info_minor_unregister(void);
#else
#define snd_info_minor_register() /* NOP */
#define snd_info_minor_unregister() /* NOP */
#endif


#ifdef CONFIG_PROC_FS

extern struct snd_info_entry *snd_seq_root;
#ifdef CONFIG_SND_OSSEMUL
extern struct snd_info_entry *snd_oss_root;
void snd_card_info_read_oss(struct snd_info_buffer *buffer);
#else
#define snd_oss_root NULL
static inline void snd_card_info_read_oss(struct snd_info_buffer *buffer) {}
#endif

__printf(2, 3)
int snd_iprintf(struct snd_info_buffer *buffer, const char *fmt, ...);
int snd_info_init(void);
int snd_info_done(void);

int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len);
const char *snd_info_get_str(char *dest, const char *src, int len);
struct snd_info_entry *snd_info_create_module_entry(struct module *module,
					       const char *name,
					       struct snd_info_entry *parent);
struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
					     const char *name,
					     struct snd_info_entry *parent);
void snd_info_free_entry(struct snd_info_entry *entry);
int snd_info_store_text(struct snd_info_entry *entry);
int snd_info_restore_text(struct snd_info_entry *entry);

int snd_info_card_create(struct snd_card *card);
int snd_info_card_register(struct snd_card *card);
int snd_info_card_free(struct snd_card *card);
void snd_info_card_disconnect(struct snd_card *card);
void snd_info_card_id_change(struct snd_card *card);
int snd_info_register(struct snd_info_entry *entry);

/* for card drivers */
int snd_card_proc_new(struct snd_card *card, const char *name,
		      struct snd_info_entry **entryp);

static inline void snd_info_set_text_ops(struct snd_info_entry *entry, 
	void *private_data,
	void (*read)(struct snd_info_entry *, struct snd_info_buffer *))
{
	entry->private_data = private_data;
	entry->c.text.read = read;
}

int snd_info_check_reserved_words(const char *str);

#else

#define snd_seq_root NULL
#define snd_oss_root NULL

static inline int snd_iprintf(struct snd_info_buffer *buffer, char *fmt, ...) { return 0; }
static inline int snd_info_init(void) { return 0; }
static inline int snd_info_done(void) { return 0; }

static inline int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len) { return 0; }
static inline char *snd_info_get_str(char *dest, char *src, int len) { return NULL; }
static inline struct snd_info_entry *snd_info_create_module_entry(struct module *module, const char *name, struct snd_info_entry *parent) { return NULL; }
static inline struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card, const char *name, struct snd_info_entry *parent) { return NULL; }
static inline void snd_info_free_entry(struct snd_info_entry *entry) { ; }

static inline int snd_info_card_create(struct snd_card *card) { return 0; }
static inline int snd_info_card_register(struct snd_card *card) { return 0; }
static inline int snd_info_card_free(struct snd_card *card) { return 0; }
static inline void snd_info_card_disconnect(struct snd_card *card) { }
static inline void snd_info_card_id_change(struct snd_card *card) { }
static inline int snd_info_register(struct snd_info_entry *entry) { return 0; }

static inline int snd_card_proc_new(struct snd_card *card, const char *name,
				    struct snd_info_entry **entryp) { return -EINVAL; }
static inline void snd_info_set_text_ops(struct snd_info_entry *entry __attribute__((unused)),
					 void *private_data,
					 void (*read)(struct snd_info_entry *, struct snd_info_buffer *)) {}

static inline int snd_info_check_reserved_words(const char *str) { return 1; }

#endif

/*
 * OSS info part
 */

#if defined(CONFIG_SND_OSSEMUL) && defined(CONFIG_PROC_FS)

#define SNDRV_OSS_INFO_DEV_AUDIO	0
#define SNDRV_OSS_INFO_DEV_SYNTH	1
#define SNDRV_OSS_INFO_DEV_MIDI		2
#define SNDRV_OSS_INFO_DEV_TIMERS	4
#define SNDRV_OSS_INFO_DEV_MIXERS	5

#define SNDRV_OSS_INFO_DEV_COUNT	6

int snd_oss_info_register(int dev, int num, char *string);
#define snd_oss_info_unregister(dev, num) snd_oss_info_register(dev, num, NULL)

#endif /* CONFIG_SND_OSSEMUL && CONFIG_PROC_FS */

#endif /* __SOUND_INFO_H */
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