From 913f3ec280abddc111a49287a59b658b6b181c4c Mon Sep 17 00:00:00 2001 From: Ezequiel Garcia Date: Thu, 18 Oct 2018 14:02:20 -0400 Subject: [PATCH] media: mem2mem: Require capture and output mutexes to match Currently, all the mem2mem driver either use a single mutex to lock the capture and output videobuf2 queues, or don't set any mutex. This means the mutexes match, and so the mem2mem framework is able to set the m2m context lock. Enforce this by making it mandatory for drivers to set the same capture and output mutex, or not set any mutex at all. Signed-off-by: Ezequiel Garcia Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/v4l2-core/v4l2-mem2mem.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/media/v4l2-core/v4l2-mem2mem.c b/drivers/media/v4l2-core/v4l2-mem2mem.c index 1ed2465972ac..932728841a38 100644 --- a/drivers/media/v4l2-core/v4l2-mem2mem.c +++ b/drivers/media/v4l2-core/v4l2-mem2mem.c @@ -908,12 +908,14 @@ struct v4l2_m2m_ctx *v4l2_m2m_ctx_init(struct v4l2_m2m_dev *m2m_dev, if (ret) goto err; /* - * If both queues use same mutex assign it as the common buffer - * queues lock to the m2m context. This lock is used in the - * v4l2_m2m_ioctl_* helpers. + * Both queues should use same the mutex to lock the m2m context. + * This lock is used in some v4l2_m2m_* helpers. */ - if (out_q_ctx->q.lock == cap_q_ctx->q.lock) - m2m_ctx->q_lock = out_q_ctx->q.lock; + if (WARN_ON(out_q_ctx->q.lock != cap_q_ctx->q.lock)) { + ret = -EINVAL; + goto err; + } + m2m_ctx->q_lock = out_q_ctx->q.lock; return m2m_ctx; err: -- 2.30.2