This is a note to let you know that I've just added the patch titled media: sti/bdisp: fix pm_runtime_get_sync() usage count to the 5.12-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: media-sti-bdisp-fix-pm_runtime_get_sync-usage-count.patch and it can be found in the queue-5.12 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit a2414f4fc175a1a465d5fa13b3b987c536acac02 Author: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> Date: Fri Apr 23 17:19:21 2021 +0200 media: sti/bdisp: fix pm_runtime_get_sync() usage count [ Upstream commit c44eac5b72e23c31eefc0e10a71d9650036b8341 ] The pm_runtime_get_sync() internally increments the dev->power.usage_count without decrementing it, even on errors. The bdisp_start_streaming() doesn't take it into account, which would unbalance PM usage counter at bdisp_stop_streaming(). The logic at bdisp_probe() is correct, but the best is to use the same call along the driver. So, replace it by the new pm_runtime_resume_and_get(), introduced by: commit dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter") in order to properly decrement the usage counter, avoiding a potential PM usage counter leak. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/media/platform/sti/bdisp/bdisp-v4l2.c b/drivers/media/platform/sti/bdisp/bdisp-v4l2.c index 060ca85f64d5..85288da9d2ae 100644 --- a/drivers/media/platform/sti/bdisp/bdisp-v4l2.c +++ b/drivers/media/platform/sti/bdisp/bdisp-v4l2.c @@ -499,7 +499,7 @@ static int bdisp_start_streaming(struct vb2_queue *q, unsigned int count) { struct bdisp_ctx *ctx = q->drv_priv; struct vb2_v4l2_buffer *buf; - int ret = pm_runtime_get_sync(ctx->bdisp_dev->dev); + int ret = pm_runtime_resume_and_get(ctx->bdisp_dev->dev); if (ret < 0) { dev_err(ctx->bdisp_dev->dev, "failed to set runtime PM\n"); @@ -1364,10 +1364,10 @@ static int bdisp_probe(struct platform_device *pdev) /* Power management */ pm_runtime_enable(dev); - ret = pm_runtime_get_sync(dev); + ret = pm_runtime_resume_and_get(dev); if (ret < 0) { dev_err(dev, "failed to set PM\n"); - goto err_pm; + goto err_remove; } /* Filters */ @@ -1395,6 +1395,7 @@ err_filter: bdisp_hw_free_filters(bdisp->dev); err_pm: pm_runtime_put(dev); +err_remove: bdisp_debugfs_remove(bdisp); v4l2_device_unregister(&bdisp->v4l2_dev); err_clk: