6.6-stable review patch. If anyone has any objections, please let me know.
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From: Peter Ujfalusi peter.ujfalusi@linux.intel.com
[ Upstream commit 576a0b71b5b479008dacb3047a346625040f5ac6 ]
In the existing IPC support, the reply to each IPC message is handled in an IRQ thread. The assumption is that the IRQ thread is scheduled without significant delays.
On an experimental (iow, buggy) kernel, the IRQ thread dealing with the reply to the last IPC message before powering-down the DSP can be delayed by several seconds. The IRQ thread will proceed with register accesses after the DSP is powered-down which results in a kernel crash.
While the bug which causes the delay is not in the audio stack, we must handle such cases with defensive programming to avoid such crashes.
Call synchronize_irq() before proceeding to power down the DSP to make sure that no irq thread is pending execution.
Closes: https://github.com/thesofproject/linux/issues/4608 Reviewed-by: Guennadi Liakhovetski guennadi.liakhovetski@linux.intel.com Signed-off-by: Peter Ujfalusi peter.ujfalusi@linux.intel.com Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Link: https://lore.kernel.org/r/20231012191850.147140-3-pierre-louis.bossart@linux... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- sound/soc/sof/intel/hda-dsp.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/sound/soc/sof/intel/hda-dsp.c b/sound/soc/sof/intel/hda-dsp.c index e80a2a5ec56a1..1506982a56c30 100644 --- a/sound/soc/sof/intel/hda-dsp.c +++ b/sound/soc/sof/intel/hda-dsp.c @@ -709,6 +709,9 @@ static int hda_suspend(struct snd_sof_dev *sdev, bool runtime_suspend) if (ret < 0) return ret;
+ /* make sure that no irq handler is pending before shutdown */ + synchronize_irq(sdev->ipc_irq); + hda_codec_jack_wake_enable(sdev, runtime_suspend);
/* power down all hda links */