Revision bbdc74dc19e09ac4e71bfb219596b3d5bc786720 authored by Grzegorz Sluja on 13 July 2017, 09:17:58 UTC, committed by Ulf Hansson on 13 July 2017, 09:44:01 UTC
The commit 304419d8a7e9 ("mmc: core: Allocate per-request data using the
block layer core"), refactored the mechanism of queue handling, but also
made mmc_init_request() to be called after mmc_cleanup_queue(). This
triggers a null pointer dereference:

[  683.123791] BUG: unable to handle kernel NULL pointer dereference at (null)
[  683.123801] IP: mmc_init_request+0x2c/0xf0 [mmc_block]
...
[  683.123905] Call Trace:
[  683.123913]  alloc_request_size+0x4f/0x70
[  683.123919]  mempool_alloc+0x5f/0x150
[  683.123925]  ? __enqueue_entity+0x6c/0x70
[  683.123928]  get_request+0x3ad/0x720
[  683.123933]  ? prepare_to_wait_event+0x110/0x110
[  683.123937]  blk_queue_bio+0xc1/0x3a0
[  683.123940]  generic_make_request+0xf8/0x2a0
[  683.123942]  submit_bio+0x75/0x150
[  683.123947]  submit_bio_wait+0x51/0x70
[  683.123951]  blkdev_issue_flush+0x5c/0x90
[  683.123956]  ext4_sync_fs+0x171/0x1b0
[  683.123961]  sync_filesystem+0x73/0x90
[  683.123965]  fsync_bdev+0x24/0x50
[  683.123971]  invalidate_partition+0x24/0x50
[  683.123973]  del_gendisk+0xb2/0x2a0
[  683.123977]  mmc_blk_remove_req.part.38+0x71/0xa0 [mmc_block]
[  683.123980]  mmc_blk_remove+0xba/0x190 [mmc_block]
[  683.123990]  mmc_bus_remove+0x1a/0x20 [mmc_core]
[  683.123995]  device_release_driver_internal+0x141/0x200
[  683.123999]  device_release_driver+0x12/0x20
[  683.124001]  bus_remove_device+0xfd/0x170
[  683.124004]  device_del+0x1e8/0x330
[  683.124012]  mmc_remove_card+0x60/0xc0 [mmc_core]
[  683.124019]  mmc_remove+0x19/0x30 [mmc_core]
[  683.124025]  mmc_stop_host+0xfb/0x1a0 [mmc_core]
[  683.124032]  mmc_remove_host+0x1a/0x40 [mmc_core]
[  683.124037]  sdhci_remove_host+0x2e/0x1c0 [mmc_sdhci]
[  683.124042]  sdhci_pci_remove_slot+0x3f/0x80 [sdhci_pci]
[  683.124045]  sdhci_pci_remove+0x39/0x70 [sdhci_pci]
[  683.124049]  pci_device_remove+0x39/0xc0
[  683.124052]  device_release_driver_internal+0x141/0x200
[  683.124056]  driver_detach+0x3f/0x80
[  683.124059]  bus_remove_driver+0x55/0xd0
[  683.124062]  driver_unregister+0x2c/0x50
[  683.124065]  pci_unregister_driver+0x29/0x90
[  683.124069]  sdhci_driver_exit+0x10/0x4f3 [sdhci_pci]
[  683.124073]  SyS_delete_module+0x171/0x250
[  683.124078]  entry_SYSCALL_64_fastpath+0x1e/0xa9

Fix this by setting the queue DYING flag before cleanup the queue, as it
prevents new reqs from entering the queue.

Signed-off-by: Grzegorz Sluja <grzegorzx.sluja@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Fixes: 304419d8a7e9 ("mmc: core: Allocate per-request data using the...")
[Ulf: Updated the changelog]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
1 parent aab2ee0
Raw File
seq_virmidi.h
#ifndef __SOUND_SEQ_VIRMIDI_H
#define __SOUND_SEQ_VIRMIDI_H

/*
 *  Virtual Raw MIDI client on Sequencer
 *  Copyright (c) 2000 by Takashi Iwai <tiwai@suse.de>,
 *                        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 <sound/rawmidi.h>
#include <sound/seq_midi_event.h>

/*
 * device file instance:
 * This instance is created at each time the midi device file is
 * opened.  Each instance has its own input buffer and MIDI parser
 * (buffer), and is associated with the device instance.
 */
struct snd_virmidi {
	struct list_head list;
	int seq_mode;
	int client;
	int port;
	unsigned int trigger: 1;
	struct snd_midi_event *parser;
	struct snd_seq_event event;
	struct snd_virmidi_dev *rdev;
	struct snd_rawmidi_substream *substream;
};

#define SNDRV_VIRMIDI_SUBSCRIBE		(1<<0)
#define SNDRV_VIRMIDI_USE		(1<<1)

/*
 * device record:
 * Each virtual midi device has one device instance.  It contains
 * common information and the linked-list of opened files, 
 */
struct snd_virmidi_dev {
	struct snd_card *card;		/* associated card */
	struct snd_rawmidi *rmidi;		/* rawmidi device */
	int seq_mode;			/* SNDRV_VIRMIDI_XXX */
	int device;			/* sequencer device */
	int client;			/* created/attached client */
	int port;			/* created/attached port */
	unsigned int flags;		/* SNDRV_VIRMIDI_* */
	rwlock_t filelist_lock;
	struct list_head filelist;
};

/* sequencer mode:
 * ATTACH = input/output events from midi device are routed to the
 *          attached sequencer port.  sequencer port is not created
 *          by virmidi itself.
 *          the input to rawmidi must be processed by passing the
 *          incoming events via snd_virmidi_receive()
 * DISPATCH = input/output events are routed to subscribers.
 *            sequencer port is created in virmidi.
 */
#define SNDRV_VIRMIDI_SEQ_NONE		0
#define SNDRV_VIRMIDI_SEQ_ATTACH	1
#define SNDRV_VIRMIDI_SEQ_DISPATCH	2

int snd_virmidi_new(struct snd_card *card, int device, struct snd_rawmidi **rrmidi);

#endif /* __SOUND_SEQ_VIRMIDI */
back to top