From: Benoit Parrot Date: Wed, 15 Jul 2015 21:00:06 +0000 (-0300) Subject: media: am437x-vpfe: Fix a race condition during release X-Git-Tag: v4.1.9~110 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=c7f2670397e5a1ecfeb3fe5995306d44ba911404;p=users%2Fjedix%2Flinux-maple.git media: am437x-vpfe: Fix a race condition during release commit c99235fa3ef833c3c23926085f2bb68851c8460a upstream. 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") Signed-off-by: Benoit Parrot Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/media/platform/am437x/am437x-vpfe.c b/drivers/media/platform/am437x/am437x-vpfe.c index 4e86f8d8ca26f..ddf59ee5ca400 100644 --- a/drivers/media/platform/am437x/am437x-vpfe.c +++ b/drivers/media/platform/am437x/am437x-vpfe.c @@ -1185,14 +1185,24 @@ 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;