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Keyon Jie
7fd572e7d3
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] <Interrupt>
[ 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 <xun2.zhang@intel.com>
Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.