snd/PCM: fasync BKL pushdown

Chances are this is unneeded, but the code is twisty enough that it is hard
to tell.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 61f5d425b6305660e8cd3bf514664c1f9b225c58..c49b9d9e303c76d6495943b5b99fb02eff710e1f 100644 (file)
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -22,6 +22,7 @@
 #include <linux/mm.h>
 #include <linux/file.h>
 #include <linux/slab.h>
+#include <linux/smp_lock.h>
 #include <linux/time.h>
 #include <linux/pm_qos_params.h>
 #include <linux/uio.h>
@@ -3249,14 +3250,17 @@ static int snd_pcm_fasync(int fd, struct file * file, int on)
        struct snd_pcm_file * pcm_file;
        struct snd_pcm_substream *substream;
        struct snd_pcm_runtime *runtime;
-       int err;
+       int err = -ENXIO;
 
+       lock_kernel();
        pcm_file = file->private_data;
        substream = pcm_file->substream;
-       snd_assert(substream != NULL, return -ENXIO);
+       snd_assert(substream != NULL, goto out);
        runtime = substream->runtime;
 
        err = fasync_helper(fd, file, on, &runtime->fasync);
+out:
+       unlock_kernel();
        if (err < 0)
                return err;
        return 0;