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
decompressor_multi.c
/*
* Copyright (c) 2013
* Minchan Kim <minchan@kernel.org>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*/
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/buffer_head.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/cpumask.h>
#include "squashfs_fs.h"
#include "squashfs_fs_sb.h"
#include "decompressor.h"
#include "squashfs.h"
/*
* This file implements multi-threaded decompression in the
* decompressor framework
*/
/*
* The reason that multiply two is that a CPU can request new I/O
* while it is waiting previous request.
*/
#define MAX_DECOMPRESSOR (num_online_cpus() * 2)
int squashfs_max_decompressors(void)
{
return MAX_DECOMPRESSOR;
}
struct squashfs_stream {
void *comp_opts;
struct list_head strm_list;
struct mutex mutex;
int avail_decomp;
wait_queue_head_t wait;
};
struct decomp_stream {
void *stream;
struct list_head list;
};
static void put_decomp_stream(struct decomp_stream *decomp_strm,
struct squashfs_stream *stream)
{
mutex_lock(&stream->mutex);
list_add(&decomp_strm->list, &stream->strm_list);
mutex_unlock(&stream->mutex);
wake_up(&stream->wait);
}
void *squashfs_decompressor_create(struct squashfs_sb_info *msblk,
void *comp_opts)
{
struct squashfs_stream *stream;
struct decomp_stream *decomp_strm = NULL;
int err = -ENOMEM;
stream = kzalloc(sizeof(*stream), GFP_KERNEL);
if (!stream)
goto out;
stream->comp_opts = comp_opts;
mutex_init(&stream->mutex);
INIT_LIST_HEAD(&stream->strm_list);
init_waitqueue_head(&stream->wait);
/*
* We should have a decompressor at least as default
* so if we fail to allocate new decompressor dynamically,
* we could always fall back to default decompressor and
* file system works.
*/
decomp_strm = kmalloc(sizeof(*decomp_strm), GFP_KERNEL);
if (!decomp_strm)
goto out;
decomp_strm->stream = msblk->decompressor->init(msblk,
stream->comp_opts);
if (IS_ERR(decomp_strm->stream)) {
err = PTR_ERR(decomp_strm->stream);
goto out;
}
list_add(&decomp_strm->list, &stream->strm_list);
stream->avail_decomp = 1;
return stream;
out:
kfree(decomp_strm);
kfree(stream);
return ERR_PTR(err);
}
void squashfs_decompressor_destroy(struct squashfs_sb_info *msblk)
{
struct squashfs_stream *stream = msblk->stream;
if (stream) {
struct decomp_stream *decomp_strm;
while (!list_empty(&stream->strm_list)) {
decomp_strm = list_entry(stream->strm_list.prev,
struct decomp_stream, list);
list_del(&decomp_strm->list);
msblk->decompressor->free(decomp_strm->stream);
kfree(decomp_strm);
stream->avail_decomp--;
}
WARN_ON(stream->avail_decomp);
kfree(stream->comp_opts);
kfree(stream);
}
}
static struct decomp_stream *get_decomp_stream(struct squashfs_sb_info *msblk,
struct squashfs_stream *stream)
{
struct decomp_stream *decomp_strm;
while (1) {
mutex_lock(&stream->mutex);
/* There is available decomp_stream */
if (!list_empty(&stream->strm_list)) {
decomp_strm = list_entry(stream->strm_list.prev,
struct decomp_stream, list);
list_del(&decomp_strm->list);
mutex_unlock(&stream->mutex);
break;
}
/*
* If there is no available decomp and already full,
* let's wait for releasing decomp from other users.
*/
if (stream->avail_decomp >= MAX_DECOMPRESSOR)
goto wait;
/* Let's allocate new decomp */
decomp_strm = kmalloc(sizeof(*decomp_strm), GFP_KERNEL);
if (!decomp_strm)
goto wait;
decomp_strm->stream = msblk->decompressor->init(msblk,
stream->comp_opts);
if (IS_ERR(decomp_strm->stream)) {
kfree(decomp_strm);
goto wait;
}
stream->avail_decomp++;
WARN_ON(stream->avail_decomp > MAX_DECOMPRESSOR);
mutex_unlock(&stream->mutex);
break;
wait:
/*
* If system memory is tough, let's for other's
* releasing instead of hurting VM because it could
* make page cache thrashing.
*/
mutex_unlock(&stream->mutex);
wait_event(stream->wait,
!list_empty(&stream->strm_list));
}
return decomp_strm;
}
int squashfs_decompress(struct squashfs_sb_info *msblk, struct buffer_head **bh,
int b, int offset, int length, struct squashfs_page_actor *output)
{
int res;
struct squashfs_stream *stream = msblk->stream;
struct decomp_stream *decomp_stream = get_decomp_stream(msblk, stream);
res = msblk->decompressor->decompress(msblk, decomp_stream->stream,
bh, b, offset, length, output);
put_decomp_stream(decomp_stream, stream);
if (res < 0)
ERROR("%s decompression failed, data probably corrupt\n",
msblk->decompressor->name);
return res;
}
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