3.5.7.26 -stable review patch.  If anyone has any objections, please let me 
know.

------------------

From: Takashi Iwai <ti...@suse.de>

commit 8b8d654b55648561287bd8baca0f75f964a17038 upstream.

The codes to initialize work struct or create a proc interface should
be called only once and never although it's called many times through
the init callback.  Move that stuff into patch_generic_hdmi() so that
it's called only once.

Signed-off-by: Takashi Iwai <ti...@suse.de>

This is being backported to 3.4 and 3.5 due to prevention of kernel
panic. The kernel panic was observed by executing
'cat /proc/asound/card0/codec0' on a particular machine, which was
 - running in battery mode
 - having an external HDMI monitor connected
 - running the fglrx driver.

In short, the one-time init code initializes a delayed_work struct.
Then, I believe the following happened:
 1) the delayed_work was activated
 2) the delayed_work struct was reinitialized by the init code
 3) when the delayed_work timed out (ready to run the callback function),
    the kernel panic happened because the delayed_work struct had
    been corrupted in step 2.

BugLink: https://bugs.launchpad.net/bugs/1212160
Signed-off-by: David Henningsson <david.hennings...@canonical.com>
Signed-off-by: Luis Henriques <luis.henriq...@canonical.com>
---
 sound/pci/hda/patch_hdmi.c | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index c3cd1f8..769ba9b 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -1283,23 +1283,34 @@ static int generic_hdmi_build_controls(struct hda_codec 
*codec)
        return 0;
 }
 
-static int generic_hdmi_init(struct hda_codec *codec)
+static int generic_hdmi_init_per_pins(struct hda_codec *codec)
 {
        struct hdmi_spec *spec = codec->spec;
        int pin_idx;
 
        for (pin_idx = 0; pin_idx < spec->num_pins; pin_idx++) {
                struct hdmi_spec_per_pin *per_pin = &spec->pins[pin_idx];
-               hda_nid_t pin_nid = per_pin->pin_nid;
                struct hdmi_eld *eld = &per_pin->sink_eld;
 
-               hdmi_init_pin(codec, pin_nid);
-               snd_hda_jack_detect_enable(codec, pin_nid, pin_nid);
-
                per_pin->codec = codec;
                INIT_DELAYED_WORK(&per_pin->work, hdmi_repoll_eld);
                snd_hda_eld_proc_new(codec, eld, pin_idx);
        }
+       return 0;
+}
+
+static int generic_hdmi_init(struct hda_codec *codec)
+{
+       struct hdmi_spec *spec = codec->spec;
+       int pin_idx;
+
+       for (pin_idx = 0; pin_idx < spec->num_pins; pin_idx++) {
+               struct hdmi_spec_per_pin *per_pin = &spec->pins[pin_idx];
+               hda_nid_t pin_nid = per_pin->pin_nid;
+
+               hdmi_init_pin(codec, pin_nid);
+               snd_hda_jack_detect_enable(codec, pin_nid, pin_nid);
+       }
        snd_hda_jack_report_sync(codec);
        return 0;
 }
@@ -1344,6 +1355,7 @@ static int patch_generic_hdmi(struct hda_codec *codec)
                return -EINVAL;
        }
        codec->patch_ops = generic_hdmi_patch_ops;
+       generic_hdmi_init_per_pins(codec);
 
        init_channel_allocations();
 
-- 
1.8.3.2

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