summaryrefslogtreecommitdiff
path: root/sound/hda
diff options
context:
space:
mode:
authorPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>2021-09-24 22:24:16 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2021-11-25 11:49:08 +0300
commit01085644673f73b47b5c3dae162a542b98e15c90 (patch)
treef3942fa174844d685f1a73666793e345a0c0f622 /sound/hda
parentfaed25ba98db9e610260d429eced20ca352b3db2 (diff)
downloadlinux-01085644673f73b47b5c3dae162a542b98e15c90.tar.xz
ALSA: hda: hdac_ext_stream: fix potential locking issues
commit 868ddfcef31ff93ea8961b2e81ea7fe12f6f144b upstream. The code for hdac_ext_stream seems inherited from hdac_stream, and similar locking issues are present: the use of the bus->reg_lock spinlock is inconsistent, with only writes to specific fields being protected. Apply similar fix as in hdac_stream by protecting all accesses to 'link_locked' and 'decoupled' fields, with a new helper snd_hdac_ext_stream_decouple_locked() added to simplify code changes. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Link: https://lore.kernel.org/r/20210924192417.169243-4-pierre-louis.bossart@linux.intel.com Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'sound/hda')
-rw-r--r--sound/hda/ext/hdac_ext_stream.c46
1 files changed, 28 insertions, 18 deletions
diff --git a/sound/hda/ext/hdac_ext_stream.c b/sound/hda/ext/hdac_ext_stream.c
index 0c005d67fa89..37154ed43bd5 100644
--- a/sound/hda/ext/hdac_ext_stream.c
+++ b/sound/hda/ext/hdac_ext_stream.c
@@ -106,20 +106,14 @@ void snd_hdac_stream_free_all(struct hdac_bus *bus)
}
EXPORT_SYMBOL_GPL(snd_hdac_stream_free_all);
-/**
- * snd_hdac_ext_stream_decouple - decouple the hdac stream
- * @bus: HD-audio core bus
- * @stream: HD-audio ext core stream object to initialize
- * @decouple: flag to decouple
- */
-void snd_hdac_ext_stream_decouple(struct hdac_bus *bus,
- struct hdac_ext_stream *stream, bool decouple)
+void snd_hdac_ext_stream_decouple_locked(struct hdac_bus *bus,
+ struct hdac_ext_stream *stream,
+ bool decouple)
{
struct hdac_stream *hstream = &stream->hstream;
u32 val;
int mask = AZX_PPCTL_PROCEN(hstream->index);
- spin_lock_irq(&bus->reg_lock);
val = readw(bus->ppcap + AZX_REG_PP_PPCTL) & mask;
if (decouple && !val)
@@ -128,6 +122,20 @@ void snd_hdac_ext_stream_decouple(struct hdac_bus *bus,
snd_hdac_updatel(bus->ppcap, AZX_REG_PP_PPCTL, mask, 0);
stream->decoupled = decouple;
+}
+EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_decouple_locked);
+
+/**
+ * snd_hdac_ext_stream_decouple - decouple the hdac stream
+ * @bus: HD-audio core bus
+ * @stream: HD-audio ext core stream object to initialize
+ * @decouple: flag to decouple
+ */
+void snd_hdac_ext_stream_decouple(struct hdac_bus *bus,
+ struct hdac_ext_stream *stream, bool decouple)
+{
+ spin_lock_irq(&bus->reg_lock);
+ snd_hdac_ext_stream_decouple_locked(bus, stream, decouple);
spin_unlock_irq(&bus->reg_lock);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_decouple);
@@ -252,6 +260,7 @@ hdac_ext_link_stream_assign(struct hdac_bus *bus,
return NULL;
}
+ spin_lock_irq(&bus->reg_lock);
list_for_each_entry(stream, &bus->stream_list, list) {
struct hdac_ext_stream *hstream = container_of(stream,
struct hdac_ext_stream,
@@ -266,17 +275,16 @@ hdac_ext_link_stream_assign(struct hdac_bus *bus,
}
if (!hstream->link_locked) {
- snd_hdac_ext_stream_decouple(bus, hstream, true);
+ snd_hdac_ext_stream_decouple_locked(bus, hstream, true);
res = hstream;
break;
}
}
if (res) {
- spin_lock_irq(&bus->reg_lock);
res->link_locked = 1;
res->link_substream = substream;
- spin_unlock_irq(&bus->reg_lock);
}
+ spin_unlock_irq(&bus->reg_lock);
return res;
}
@@ -292,6 +300,7 @@ hdac_ext_host_stream_assign(struct hdac_bus *bus,
return NULL;
}
+ spin_lock_irq(&bus->reg_lock);
list_for_each_entry(stream, &bus->stream_list, list) {
struct hdac_ext_stream *hstream = container_of(stream,
struct hdac_ext_stream,
@@ -301,18 +310,17 @@ hdac_ext_host_stream_assign(struct hdac_bus *bus,
if (!stream->opened) {
if (!hstream->decoupled)
- snd_hdac_ext_stream_decouple(bus, hstream, true);
+ snd_hdac_ext_stream_decouple_locked(bus, hstream, true);
res = hstream;
break;
}
}
if (res) {
- spin_lock_irq(&bus->reg_lock);
res->hstream.opened = 1;
res->hstream.running = 0;
res->hstream.substream = substream;
- spin_unlock_irq(&bus->reg_lock);
}
+ spin_unlock_irq(&bus->reg_lock);
return res;
}
@@ -378,15 +386,17 @@ void snd_hdac_ext_stream_release(struct hdac_ext_stream *stream, int type)
break;
case HDAC_EXT_STREAM_TYPE_HOST:
+ spin_lock_irq(&bus->reg_lock);
if (stream->decoupled && !stream->link_locked)
- snd_hdac_ext_stream_decouple(bus, stream, false);
+ snd_hdac_ext_stream_decouple_locked(bus, stream, false);
+ spin_unlock_irq(&bus->reg_lock);
snd_hdac_stream_release(&stream->hstream);
break;
case HDAC_EXT_STREAM_TYPE_LINK:
- if (stream->decoupled && !stream->hstream.opened)
- snd_hdac_ext_stream_decouple(bus, stream, false);
spin_lock_irq(&bus->reg_lock);
+ if (stream->decoupled && !stream->hstream.opened)
+ snd_hdac_ext_stream_decouple_locked(bus, stream, false);
stream->link_locked = 0;
stream->link_substream = NULL;
spin_unlock_irq(&bus->reg_lock);