The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 81302b1c7c997e8a56c1c2fc63a296ebeb0cd2d0
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023052649-kilt-concert-cd8a@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
81302b1c7c99 ("ALSA: hda: Fix unhandled register update during auto-suspend period")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 81302b1c7c997e8a56c1c2fc63a296ebeb0cd2d0 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai(a)suse.de>
Date: Thu, 18 May 2023 13:35:20 +0200
Subject: [PATCH] ALSA: hda: Fix unhandled register update during auto-suspend
period
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
It's reported that the recording started right after the driver probe
doesn't work properly, and it turned out that this is related with the
codec auto-suspend. Namely, after the probe phase, the usage count
goes zero, and the auto-suspend is programmed, but the codec is kept
still active until the auto-suspend expiration. When an application
(e.g. alsactl) updates the mixer values at this moment, the values are
cached but not actually written. Then, starting arecord thereafter
also results in the silence because of the missing unmute.
The root cause is the handling of "lazy update" mode; when a mixer
value is updated *after* the suspend, it should update only the cache
and exits. At the resume, the cached value is written to the device,
in turn. The problem is that the current code misinterprets the state
of auto-suspend as if it were already suspended.
Although we can add the check of the actual device state after
pm_runtime_get_if_in_use() for catching the missing state, this won't
suffice; the second call of regmap_update_bits_check() will skip
writing the register because the cache has been already updated by the
first call. So we'd need fixes in two different places.
OTOH, a simpler fix is to replace pm_runtime_get_if_in_use() with
pm_runtime_get_if_active() (with ign_usage_count=true). This change
implies that the driver takes the pm refcount if the device is still
in ACTIVE state and continues the processing. A small caveat is that
this will leave the auto-suspend timer. But, since the timer callback
itself checks the device state and aborts gracefully when it's active,
this won't be any substantial problem.
Long story short: we address the missing register-write problem just
by replacing the pm_runtime_*() call in snd_hda_keep_power_up().
Fixes: fc4f000bf8c0 ("ALSA: hda - Fix unexpected resume through regmap code path")
Reported-by: Amadeusz Sławiński <amadeuszx.slawinski(a)linux.intel.com>
Closes: https://lore.kernel.org/r/a7478636-af11-92ab-731c-9b13c582a70d@linux.intel.…
Suggested-by: Cezary Rojewski <cezary.rojewski(a)intel.com>
Cc: <stable(a)vger.kernel.org>
Link: https://lore.kernel.org/r/20230518113520.15213-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai(a)suse.de>
diff --git a/sound/hda/hdac_device.c b/sound/hda/hdac_device.c
index accc9d279ce5..6c043fbd606f 100644
--- a/sound/hda/hdac_device.c
+++ b/sound/hda/hdac_device.c
@@ -611,7 +611,7 @@ EXPORT_SYMBOL_GPL(snd_hdac_power_up_pm);
int snd_hdac_keep_power_up(struct hdac_device *codec)
{
if (!atomic_inc_not_zero(&codec->in_pm)) {
- int ret = pm_runtime_get_if_in_use(&codec->dev);
+ int ret = pm_runtime_get_if_active(&codec->dev, true);
if (!ret)
return -1;
if (ret < 0)
The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y
git checkout FETCH_HEAD
git cherry-pick -x 81302b1c7c997e8a56c1c2fc63a296ebeb0cd2d0
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023052647-had-steering-38d3@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..
Possible dependencies:
81302b1c7c99 ("ALSA: hda: Fix unhandled register update during auto-suspend period")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 81302b1c7c997e8a56c1c2fc63a296ebeb0cd2d0 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai(a)suse.de>
Date: Thu, 18 May 2023 13:35:20 +0200
Subject: [PATCH] ALSA: hda: Fix unhandled register update during auto-suspend
period
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
It's reported that the recording started right after the driver probe
doesn't work properly, and it turned out that this is related with the
codec auto-suspend. Namely, after the probe phase, the usage count
goes zero, and the auto-suspend is programmed, but the codec is kept
still active until the auto-suspend expiration. When an application
(e.g. alsactl) updates the mixer values at this moment, the values are
cached but not actually written. Then, starting arecord thereafter
also results in the silence because of the missing unmute.
The root cause is the handling of "lazy update" mode; when a mixer
value is updated *after* the suspend, it should update only the cache
and exits. At the resume, the cached value is written to the device,
in turn. The problem is that the current code misinterprets the state
of auto-suspend as if it were already suspended.
Although we can add the check of the actual device state after
pm_runtime_get_if_in_use() for catching the missing state, this won't
suffice; the second call of regmap_update_bits_check() will skip
writing the register because the cache has been already updated by the
first call. So we'd need fixes in two different places.
OTOH, a simpler fix is to replace pm_runtime_get_if_in_use() with
pm_runtime_get_if_active() (with ign_usage_count=true). This change
implies that the driver takes the pm refcount if the device is still
in ACTIVE state and continues the processing. A small caveat is that
this will leave the auto-suspend timer. But, since the timer callback
itself checks the device state and aborts gracefully when it's active,
this won't be any substantial problem.
Long story short: we address the missing register-write problem just
by replacing the pm_runtime_*() call in snd_hda_keep_power_up().
Fixes: fc4f000bf8c0 ("ALSA: hda - Fix unexpected resume through regmap code path")
Reported-by: Amadeusz Sławiński <amadeuszx.slawinski(a)linux.intel.com>
Closes: https://lore.kernel.org/r/a7478636-af11-92ab-731c-9b13c582a70d@linux.intel.…
Suggested-by: Cezary Rojewski <cezary.rojewski(a)intel.com>
Cc: <stable(a)vger.kernel.org>
Link: https://lore.kernel.org/r/20230518113520.15213-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai(a)suse.de>
diff --git a/sound/hda/hdac_device.c b/sound/hda/hdac_device.c
index accc9d279ce5..6c043fbd606f 100644
--- a/sound/hda/hdac_device.c
+++ b/sound/hda/hdac_device.c
@@ -611,7 +611,7 @@ EXPORT_SYMBOL_GPL(snd_hdac_power_up_pm);
int snd_hdac_keep_power_up(struct hdac_device *codec)
{
if (!atomic_inc_not_zero(&codec->in_pm)) {
- int ret = pm_runtime_get_if_in_use(&codec->dev);
+ int ret = pm_runtime_get_if_active(&codec->dev, true);
if (!ret)
return -1;
if (ret < 0)
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.14.y
git checkout FETCH_HEAD
git cherry-pick -x 81302b1c7c997e8a56c1c2fc63a296ebeb0cd2d0
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023052628-overfull-secular-50e4@gregkh' --subject-prefix 'PATCH 4.14.y' HEAD^..
Possible dependencies:
81302b1c7c99 ("ALSA: hda: Fix unhandled register update during auto-suspend period")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 81302b1c7c997e8a56c1c2fc63a296ebeb0cd2d0 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai(a)suse.de>
Date: Thu, 18 May 2023 13:35:20 +0200
Subject: [PATCH] ALSA: hda: Fix unhandled register update during auto-suspend
period
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
It's reported that the recording started right after the driver probe
doesn't work properly, and it turned out that this is related with the
codec auto-suspend. Namely, after the probe phase, the usage count
goes zero, and the auto-suspend is programmed, but the codec is kept
still active until the auto-suspend expiration. When an application
(e.g. alsactl) updates the mixer values at this moment, the values are
cached but not actually written. Then, starting arecord thereafter
also results in the silence because of the missing unmute.
The root cause is the handling of "lazy update" mode; when a mixer
value is updated *after* the suspend, it should update only the cache
and exits. At the resume, the cached value is written to the device,
in turn. The problem is that the current code misinterprets the state
of auto-suspend as if it were already suspended.
Although we can add the check of the actual device state after
pm_runtime_get_if_in_use() for catching the missing state, this won't
suffice; the second call of regmap_update_bits_check() will skip
writing the register because the cache has been already updated by the
first call. So we'd need fixes in two different places.
OTOH, a simpler fix is to replace pm_runtime_get_if_in_use() with
pm_runtime_get_if_active() (with ign_usage_count=true). This change
implies that the driver takes the pm refcount if the device is still
in ACTIVE state and continues the processing. A small caveat is that
this will leave the auto-suspend timer. But, since the timer callback
itself checks the device state and aborts gracefully when it's active,
this won't be any substantial problem.
Long story short: we address the missing register-write problem just
by replacing the pm_runtime_*() call in snd_hda_keep_power_up().
Fixes: fc4f000bf8c0 ("ALSA: hda - Fix unexpected resume through regmap code path")
Reported-by: Amadeusz Sławiński <amadeuszx.slawinski(a)linux.intel.com>
Closes: https://lore.kernel.org/r/a7478636-af11-92ab-731c-9b13c582a70d@linux.intel.…
Suggested-by: Cezary Rojewski <cezary.rojewski(a)intel.com>
Cc: <stable(a)vger.kernel.org>
Link: https://lore.kernel.org/r/20230518113520.15213-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai(a)suse.de>
diff --git a/sound/hda/hdac_device.c b/sound/hda/hdac_device.c
index accc9d279ce5..6c043fbd606f 100644
--- a/sound/hda/hdac_device.c
+++ b/sound/hda/hdac_device.c
@@ -611,7 +611,7 @@ EXPORT_SYMBOL_GPL(snd_hdac_power_up_pm);
int snd_hdac_keep_power_up(struct hdac_device *codec)
{
if (!atomic_inc_not_zero(&codec->in_pm)) {
- int ret = pm_runtime_get_if_in_use(&codec->dev);
+ int ret = pm_runtime_get_if_active(&codec->dev, true);
if (!ret)
return -1;
if (ret < 0)
Dan Carpenter spotted a race condition in a couple of situations like
these in the test_firmware driver:
static int test_dev_config_update_u8(const char *buf, size_t size, u8 *cfg)
{
u8 val;
int ret;
ret = kstrtou8(buf, 10, &val);
if (ret)
return ret;
mutex_lock(&test_fw_mutex);
*(u8 *)cfg = val;
mutex_unlock(&test_fw_mutex);
/* Always return full write size even if we didn't consume all */
return size;
}
static ssize_t config_num_requests_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
int rc;
mutex_lock(&test_fw_mutex);
if (test_fw_config->reqs) {
pr_err("Must call release_all_firmware prior to changing config\n");
rc = -EINVAL;
mutex_unlock(&test_fw_mutex);
goto out;
}
mutex_unlock(&test_fw_mutex);
rc = test_dev_config_update_u8(buf, count,
&test_fw_config->num_requests);
out:
return rc;
}
static ssize_t config_read_fw_idx_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
return test_dev_config_update_u8(buf, count,
&test_fw_config->read_fw_idx);
}
The function test_dev_config_update_u8() is called from both the locked
and the unlocked context, function config_num_requests_store() and
config_read_fw_idx_store() which can both be called asynchronously as
they are driver's methods, while test_dev_config_update_u8() and siblings
change their argument pointed to by u8 *cfg or similar pointer.
To avoid deadlock on test_fw_mutex, the lock is dropped before calling
test_dev_config_update_u8() and re-acquired within test_dev_config_update_u8()
itself, but alas this creates a race condition.
Having two locks wouldn't assure a race-proof mutual exclusion.
This situation is best avoided by the introduction of a new, unlocked
function __test_dev_config_update_u8() which can be called from the locked
context and reducing test_dev_config_update_u8() to:
static int test_dev_config_update_u8(const char *buf, size_t size, u8 *cfg)
{
int ret;
mutex_lock(&test_fw_mutex);
ret = __test_dev_config_update_u8(buf, size, cfg);
mutex_unlock(&test_fw_mutex);
return ret;
}
doing the locking and calling the unlocked primitive, which enables both
locked and unlocked versions without duplication of code.
The similar approach was applied to all functions called from the locked
and the unlocked context, which safely mitigates both deadlocks and race
conditions in the driver.
__test_dev_config_update_bool(), __test_dev_config_update_u8() and
__test_dev_config_update_size_t() unlocked versions of the functions
were introduced to be called from the locked contexts as a workaround
without releasing the main driver's lock and thereof causing a race
condition.
The test_dev_config_update_bool(), test_dev_config_update_u8() and
test_dev_config_update_size_t() locked versions of the functions
are being called from driver methods without the unnecessary multiplying
of the locking and unlocking code for each method, and complicating
the code with saving of the return value across lock.
Fixes: 7feebfa487b92 ("test_firmware: add support for request_firmware_into_buf")
Cc: Luis Chamberlain <mcgrof(a)kernel.org>
Cc: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Cc: Russ Weight <russell.h.weight(a)intel.com>
Cc: Takashi Iwai <tiwai(a)suse.de>
Cc: Tianfei Zhang <tianfei.zhang(a)intel.com>
Cc: Shuah Khan <shuah(a)kernel.org>
Cc: Colin Ian King <colin.i.king(a)gmail.com>
Cc: Randy Dunlap <rdunlap(a)infradead.org>
Cc: linux-kselftest(a)vger.kernel.org
Cc: stable(a)vger.kernel.org # v5.4
Suggested-by: Dan Carpenter <error27(a)gmail.com>
Signed-off-by: Mirsad Goran Todorovac <mirsad.todorovac(a)alu.unizg.hr>
---
lib/test_firmware.c | 52 ++++++++++++++++++++++++++++++---------------
1 file changed, 35 insertions(+), 17 deletions(-)
diff --git a/lib/test_firmware.c b/lib/test_firmware.c
index 05ed84c2fc4c..35417e0af3f4 100644
--- a/lib/test_firmware.c
+++ b/lib/test_firmware.c
@@ -353,16 +353,26 @@ static ssize_t config_test_show_str(char *dst,
return len;
}
-static int test_dev_config_update_bool(const char *buf, size_t size,
+static inline int __test_dev_config_update_bool(const char *buf, size_t size,
bool *cfg)
{
int ret;
- mutex_lock(&test_fw_mutex);
if (kstrtobool(buf, cfg) < 0)
ret = -EINVAL;
else
ret = size;
+
+ return ret;
+}
+
+static int test_dev_config_update_bool(const char *buf, size_t size,
+ bool *cfg)
+{
+ int ret;
+
+ mutex_lock(&test_fw_mutex);
+ ret = __test_dev_config_update_bool(buf, size, cfg);
mutex_unlock(&test_fw_mutex);
return ret;
@@ -373,7 +383,8 @@ static ssize_t test_dev_config_show_bool(char *buf, bool val)
return snprintf(buf, PAGE_SIZE, "%d\n", val);
}
-static int test_dev_config_update_size_t(const char *buf,
+static int __test_dev_config_update_size_t(
+ const char *buf,
size_t size,
size_t *cfg)
{
@@ -384,9 +395,7 @@ static int test_dev_config_update_size_t(const char *buf,
if (ret)
return ret;
- mutex_lock(&test_fw_mutex);
*(size_t *)cfg = new;
- mutex_unlock(&test_fw_mutex);
/* Always return full write size even if we didn't consume all */
return size;
@@ -402,7 +411,7 @@ static ssize_t test_dev_config_show_int(char *buf, int val)
return snprintf(buf, PAGE_SIZE, "%d\n", val);
}
-static int test_dev_config_update_u8(const char *buf, size_t size, u8 *cfg)
+static int __test_dev_config_update_u8(const char *buf, size_t size, u8 *cfg)
{
u8 val;
int ret;
@@ -411,14 +420,23 @@ static int test_dev_config_update_u8(const char *buf, size_t size, u8 *cfg)
if (ret)
return ret;
- mutex_lock(&test_fw_mutex);
*(u8 *)cfg = val;
- mutex_unlock(&test_fw_mutex);
/* Always return full write size even if we didn't consume all */
return size;
}
+static int test_dev_config_update_u8(const char *buf, size_t size, u8 *cfg)
+{
+ int ret;
+
+ mutex_lock(&test_fw_mutex);
+ ret = __test_dev_config_update_u8(buf, size, cfg);
+ mutex_unlock(&test_fw_mutex);
+
+ return ret;
+}
+
static ssize_t test_dev_config_show_u8(char *buf, u8 val)
{
return snprintf(buf, PAGE_SIZE, "%u\n", val);
@@ -471,10 +489,10 @@ static ssize_t config_num_requests_store(struct device *dev,
mutex_unlock(&test_fw_mutex);
goto out;
}
- mutex_unlock(&test_fw_mutex);
- rc = test_dev_config_update_u8(buf, count,
- &test_fw_config->num_requests);
+ rc = __test_dev_config_update_u8(buf, count,
+ &test_fw_config->num_requests);
+ mutex_unlock(&test_fw_mutex);
out:
return rc;
@@ -518,10 +536,10 @@ static ssize_t config_buf_size_store(struct device *dev,
mutex_unlock(&test_fw_mutex);
goto out;
}
- mutex_unlock(&test_fw_mutex);
- rc = test_dev_config_update_size_t(buf, count,
- &test_fw_config->buf_size);
+ rc = __test_dev_config_update_size_t(buf, count,
+ &test_fw_config->buf_size);
+ mutex_unlock(&test_fw_mutex);
out:
return rc;
@@ -548,10 +566,10 @@ static ssize_t config_file_offset_store(struct device *dev,
mutex_unlock(&test_fw_mutex);
goto out;
}
- mutex_unlock(&test_fw_mutex);
- rc = test_dev_config_update_size_t(buf, count,
- &test_fw_config->file_offset);
+ rc = __test_dev_config_update_size_t(buf, count,
+ &test_fw_config->file_offset);
+ mutex_unlock(&test_fw_mutex);
out:
return rc;
--
2.30.2