media: v4l2-mem2mem: add lock to protect parameter num_rdy

Getting below error when using KCSAN to check the driver. Adding lock to
protect parameter num_rdy when getting the value with function:
v4l2_m2m_num_src_bufs_ready/v4l2_m2m_num_dst_bufs_ready.

kworker/u16:3: [name:report&]BUG: KCSAN: data-race in v4l2_m2m_buf_queue
kworker/u16:3: [name:report&]

kworker/u16:3: [name:report&]read-write to 0xffffff8105f35b94 of 1 bytes by task 20865 on cpu 7:
kworker/u16:3:  v4l2_m2m_buf_queue+0xd8/0x10c

Signed-off-by: Pina Chen <pina.chen@mediatek.com>
Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
This commit is contained in:
Yunfei Dong 2023-04-17 16:17:40 +08:00 committed by Hans Verkuil
parent f0b4a2c037
commit 56b5c3e67b

View File

@ -593,7 +593,14 @@ void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx,
static inline
unsigned int v4l2_m2m_num_src_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
{
return m2m_ctx->out_q_ctx.num_rdy;
unsigned int num_buf_rdy;
unsigned long flags;
spin_lock_irqsave(&m2m_ctx->out_q_ctx.rdy_spinlock, flags);
num_buf_rdy = m2m_ctx->out_q_ctx.num_rdy;
spin_unlock_irqrestore(&m2m_ctx->out_q_ctx.rdy_spinlock, flags);
return num_buf_rdy;
}
/**
@ -605,7 +612,14 @@ unsigned int v4l2_m2m_num_src_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
static inline
unsigned int v4l2_m2m_num_dst_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
{
return m2m_ctx->cap_q_ctx.num_rdy;
unsigned int num_buf_rdy;
unsigned long flags;
spin_lock_irqsave(&m2m_ctx->cap_q_ctx.rdy_spinlock, flags);
num_buf_rdy = m2m_ctx->cap_q_ctx.num_rdy;
spin_unlock_irqrestore(&m2m_ctx->cap_q_ctx.rdy_spinlock, flags);
return num_buf_rdy;
}
/**