From: Keyon Jie Date: Wed, 12 Jun 2019 17:23:41 +0000 (-0500) Subject: ASoC: SOF: Intel: hda-stream: fix a deadlock with bus->reg_lock X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=7fd572e7d317fa51049d623badb8b2874bfd0119;p=openwrt%2Fstaging%2Fblogic.git ASoC: SOF: Intel: hda-stream: fix a deadlock with bus->reg_lock We should use irq disabled mode when read/write hda registers from thread context, as we need to hold the same bus->reg_lock in interrupt context hda_dsp_stream_interrupt(), otherwise, when we are holding the lock in hda_dsp_stream_hw_free() and the interrupt arrives, we will get deadlock in the interrupt handler. Error logs like this: [ 5.603606] CPU0 [ 5.603606] ---- [ 5.603607] lock(&(&bus->reg_lock)->rlock); [ 5.603608] [ 5.603609] lock(&(&bus->reg_lock)->rlock); [ 5.603610] *** DEADLOCK *** [ 5.603611] 2 locks held by pulseaudio/2329: [ 5.603612] #0: 000000005fcf26c6 (&card->mutex/1){+.+.}, at: dpcm_fe_dai_hw_free+0x2b/0x110 [snd_soc_core] [ 5.603619] #1: 00000000ef369faf (&rtd->pcm_mutex){+.+.}, at: soc_pcm_hw_free+0x2e/0x1c0 [snd_soc_core] The fix is simple, let's switch to use spin_lock/unlock_irq(). Reported-by: Xun Zhang Signed-off-by: Keyon Jie Signed-off-by: Pierre-Louis Bossart Signed-off-by: Mark Brown --- diff --git a/sound/soc/sof/intel/hda-stream.c b/sound/soc/sof/intel/hda-stream.c index d44318040948..23cff5aca007 100644 --- a/sound/soc/sof/intel/hda-stream.c +++ b/sound/soc/sof/intel/hda-stream.c @@ -448,12 +448,12 @@ int hda_dsp_stream_hw_free(struct snd_sof_dev *sdev, struct hdac_bus *bus = sof_to_bus(sdev); u32 mask = 0x1 << stream->index; - spin_lock(&bus->reg_lock); + spin_lock_irq(&bus->reg_lock); /* couple host and link DMA if link DMA channel is idle */ if (!link_dev->link_locked) snd_sof_dsp_update_bits(sdev, HDA_DSP_PP_BAR, SOF_HDA_REG_PP_PPCTL, mask, 0); - spin_unlock(&bus->reg_lock); + spin_unlock_irq(&bus->reg_lock); return 0; }