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Marek Szyprowski 3a6adf3263
ASoC: max98090: silence lockdep warning 
Commit 08df0d9a00 ("ASoC: max98090: revert "ASoC: max98090: fix lockdep
warning"") provided a good rationale for removing separate lock for the
SHDN register access. However it restored the lockdep warning during the
system boot. To silence the lockdep warning, mark the mutex taken in the
max98090_shdn_save() function with the lockdep class dedicated for the
runtime DAPM operations: SND_SOC_DAPM_CLASS_RUNTIME. This finally fixes
the following lockdep warning observed on Exynos4412-based Odroid U3
board:

======================================================
WARNING: possible circular locking dependency detected
5.5.0-rc7-next-20200123 #7329 Not tainted
------------------------------------------------------
alsactl/1105 is trying to acquire lock:
ed4f7cf4 (&card->dapm_mutex){+.+.}, at: max98090_shdn_save+0x1c/0x28

but task is already holding lock:
edb8d49c (&card->controls_rwsem){++++}, at: snd_ctl_ioctl+0xcc/0xbb8

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&card->controls_rwsem){++++}:
       snd_ctl_add_replace+0x3c/0x84
       dapm_create_or_share_kcontrol+0x24c/0x2e0
       snd_soc_dapm_new_widgets+0x308/0x594
       snd_soc_bind_card+0x834/0xa94
       devm_snd_soc_register_card+0x34/0x6c
       odroid_audio_probe+0x288/0x34c
       platform_drv_probe+0x6c/0xa4
       really_probe+0x200/0x48c
       driver_probe_device+0x78/0x1f8
       bus_for_each_drv+0x74/0xb8
       __device_attach+0xd4/0x16c
       bus_probe_device+0x88/0x90
       deferred_probe_work_func+0x3c/0xd0
       process_one_work+0x230/0x7bc
       worker_thread+0x44/0x524
       kthread+0x130/0x164
       ret_from_fork+0x14/0x20
       0x0

-> #0 (&card->dapm_mutex){+.+.}:
       lock_acquire+0xe8/0x270
       __mutex_lock+0x9c/0xb18
       mutex_lock_nested+0x1c/0x24
       max98090_shdn_save+0x1c/0x28
       max98090_put_enum_double+0x20/0x40
       snd_ctl_ioctl+0x190/0xbb8
       ksys_ioctl+0x484/0xb10
       ret_fast_syscall+0x0/0x28
       0xbede0564

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&card->controls_rwsem);
                               lock(&card->dapm_mutex);
                               lock(&card->controls_rwsem);
  lock(&card->dapm_mutex);

 *** DEADLOCK ***

1 lock held by alsactl/1105:
 #0: edb8d49c (&card->controls_rwsem){++++}, at: snd_ctl_ioctl+0xcc/0xbb8

stack backtrace:
CPU: 2 PID: 1105 Comm: alsactl Not tainted 5.5.0-rc7-next-20200123 #7329
Hardware name: Samsung Exynos (Flattened Device Tree)
[<c01126f0>] (unwind_backtrace) from [<c010e1e8>] (show_stack+0x10/0x14)
[<c010e1e8>] (show_stack) from [<c0b5234c>] (dump_stack+0xb4/0xe0)
[<c0b5234c>] (dump_stack) from [<c018a610>] (check_noncircular+0x1ec/0x208)
[<c018a610>] (check_noncircular) from [<c018ca2c>] (__lock_acquire+0x1210/0x25ec)
[<c018ca2c>] (__lock_acquire) from [<c018e728>] (lock_acquire+0xe8/0x270)
[<c018e728>] (lock_acquire) from [<c0b71928>] (__mutex_lock+0x9c/0xb18)
[<c0b71928>] (__mutex_lock) from [<c0b723c0>] (mutex_lock_nested+0x1c/0x24)
[<c0b723c0>] (mutex_lock_nested) from [<c086097c>] (max98090_shdn_save+0x1c/0x28)
[<c086097c>] (max98090_shdn_save) from [<c08613f8>] (max98090_put_enum_double+0x20/0x40)
[<c08613f8>] (max98090_put_enum_double) from [<c0833f20>] (snd_ctl_ioctl+0x190/0xbb8)
[<c0833f20>] (snd_ctl_ioctl) from [<c02cae14>] (ksys_ioctl+0x484/0xb10)
[<c02cae14>] (ksys_ioctl) from [<c0101000>] (ret_fast_syscall+0x0/0x28)
Exception stack(0xed331fa8 to 0xed331ff0)
...

Fixes: 08df0d9a00 ("ASoC: max98090: revert "ASoC: max98090: fix lockdep warning"")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Tzung-Bi Shih <tzungbi@google.com>
Link: https://lore.kernel.org/r/20200123134046.9769-1-m.szyprowski@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-01-24 16:53:38 +00:00
arch ARM fixes for 5.5-rc: 2019-12-06 16:12:39 -08:00
block block: fix memleak of bio integrity data 2019-12-05 11:38:36 -07:00
certs certs: Add wrapper function to check blacklisted binary hash 2019-11-12 12:25:50 +11:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-11-25 19:49:58 -08:00
Documentation ASoC: rt1015: add rt1015 amplifier driver 2020-01-23 12:12:50 +00:00
drivers regulator: add regulator_equal() 2020-01-14 15:52:48 +00:00
fs 9 cifs/smb3 fixes: two timestamp fixes, one oops fix (during oplock break) for stable, two fixes found in multichannel testing, two fixes for file create when using modeforsid mount parm 2019-12-08 12:12:18 -08:00
include ASoC: dapm: add snd_soc_dapm_put_enum_double_locked 2020-01-21 17:14:53 +00:00
init init/Kconfig: fix indentation 2019-12-04 19:44:13 -08:00
ipc y2038: remove CONFIG_64BIT_TIME 2019-11-15 14:38:27 +01:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
lib lib/: fix Kconfig indentation 2019-12-07 11:00:19 -08:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm Merge branch 'akpm' (patches from Andrew) 2019-12-05 09:46:26 -08:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
samples samples/bpf: Fix broken xdp_rxq_info due to map order assumptions 2019-12-04 17:54:15 -08:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
security + Features 2019-12-03 12:51:35 -08:00
sound ASoC: max98090: silence lockdep warning 2020-01-24 16:53:38 +00:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
usr arch: sembuf.h: make uapi asm/sembuf.h self-contained 2019-12-04 19:44:14 -08:00
virt KVM: Fix jump label out_free_* in kvm_init() 2019-11-23 11:29:17 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore modpost: dump missing namespaces into a single modules.nsdeps file 2019-11-11 20:10:01 +09:00
.mailmap Merge mainline/master into arm/fixes 2019-12-05 13:18:54 -08:00
COPYING
CREDITS Linux 5.4-rc4 2019-10-29 04:43:29 -06:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
Makefile Linux 5.5-rc1 2019-12-08 14:57:55 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README 

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.