The patch ASoC: core: conditionally increase module refcount on component open has been applied to the asoc tree at https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >From b4ed6b51f356224c6c71540ed94087f7f09b84af Mon Sep 17 00:00:00 2001 From: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx> Date: Fri, 5 Apr 2019 09:57:08 -0700 Subject: [PATCH] ASoC: core: conditionally increase module refcount on component open Recently, for Intel platforms the "ignore_module_refcount" field was introduced for the component driver. In order to avoid a deadlock preventing the PCI modules from being removed even when the card was idle, the refcounts were not incremented for the device driver module during component probe. However, this change introduced a nasty side effect: the device driver module can be unloaded while a pcm stream is open. This patch proposes to change the field to be renamed as "module_get_upon_open". When this field is set, the module refcount should be incremented on pcm open amd decremented upon pcm close. This will enable modules to be removed when no PCM playback/capture happens and prevent removal when the component is actually in use. Also, align with the skylake component driver with the new name. Fixes: b450b878('ASoC: core: don't increase component module refcount unconditionally' Signed-off-by: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx> Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> --- include/sound/soc.h | 9 +++++++-- sound/soc/intel/skylake/skl-pcm.c | 2 +- sound/soc/soc-core.c | 4 ++-- 3 files changed, 10 insertions(+), 5 deletions(-) diff --git a/include/sound/soc.h b/include/sound/soc.h index 1e2be35ed36f..482b4ea87c3c 100644 --- a/include/sound/soc.h +++ b/include/sound/soc.h @@ -802,8 +802,13 @@ struct snd_soc_component_driver { int probe_order; int remove_order; - /* signal if the module handling the component cannot be removed */ - unsigned int ignore_module_refcount:1; + /* + * signal if the module handling the component should not be removed + * if a pcm is open. Setting this would prevent the module + * refcount being incremented in probe() but allow it be incremented + * when a pcm is opened and decremented when it is closed. + */ + unsigned int module_get_upon_open:1; /* bits */ unsigned int idle_bias_on:1; diff --git a/sound/soc/intel/skylake/skl-pcm.c b/sound/soc/intel/skylake/skl-pcm.c index 57031b6d4d45..9735e2412251 100644 --- a/sound/soc/intel/skylake/skl-pcm.c +++ b/sound/soc/intel/skylake/skl-pcm.c @@ -1475,7 +1475,7 @@ static const struct snd_soc_component_driver skl_component = { .ops = &skl_platform_ops, .pcm_new = skl_pcm_new, .pcm_free = skl_pcm_free, - .ignore_module_refcount = 1, /* do not increase the refcount in core */ + .module_get_upon_open = 1, /* increment refcount when a pcm is opened */ }; int skl_platform_register(struct device *dev) diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index d88757659729..46e3ab0fced4 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -947,7 +947,7 @@ static void soc_cleanup_component(struct snd_soc_component *component) snd_soc_dapm_free(snd_soc_component_get_dapm(component)); soc_cleanup_component_debugfs(component); component->card = NULL; - if (!component->driver->ignore_module_refcount) + if (!component->driver->module_get_upon_open) module_put(component->dev->driver->owner); } @@ -1381,7 +1381,7 @@ static int soc_probe_component(struct snd_soc_card *card, return 0; } - if (!component->driver->ignore_module_refcount && + if (!component->driver->module_get_upon_open && !try_module_get(component->dev->driver->owner)) return -ENODEV; -- 2.20.1 _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
