From c99235fa3ef833c3c23926085f2bb68851c8460a Mon Sep 17 00:00:00 2001 From: Benoit Parrot Date: Wed, 15 Jul 2015 18:00:06 -0300 Subject: [PATCH] [media] media: am437x-vpfe: Fix a race condition during release There was a race condition where during cleanup/release operation on-going streaming would cause a kernel panic because the hardware module was disabled prematurely with IRQ still pending. Fixes: 417d2e507edc ("[media] media: platform: add VPFE capture driver support for AM437X") Cc: # v4.0+ Signed-off-by: Benoit Parrot Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/platform/am437x/am437x-vpfe.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/media/platform/am437x/am437x-vpfe.c b/drivers/media/platform/am437x/am437x-vpfe.c index 1fed7a56c8ae..c8447fa3fd91 100644 --- a/drivers/media/platform/am437x/am437x-vpfe.c +++ b/drivers/media/platform/am437x/am437x-vpfe.c @@ -1186,14 +1186,24 @@ static int vpfe_initialize_device(struct vpfe_device *vpfe) static int vpfe_release(struct file *file) { struct vpfe_device *vpfe = video_drvdata(file); + bool fh_singular; int ret; mutex_lock(&vpfe->lock); - if (v4l2_fh_is_singular_file(file)) - vpfe_ccdc_close(&vpfe->ccdc, vpfe->pdev); + /* Save the singular status before we call the clean-up helper */ + fh_singular = v4l2_fh_is_singular_file(file); + + /* the release helper will cleanup any on-going streaming */ ret = _vb2_fop_release(file, NULL); + /* + * If this was the last open file. + * Then de-initialize hw module. + */ + if (fh_singular) + vpfe_ccdc_close(&vpfe->ccdc, vpfe->pdev); + mutex_unlock(&vpfe->lock); return ret; -- 2.39.5