6.6-stable review patch. If anyone has any objections, please let me know.
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From: Laurentiu Palcu laurentiu.palcu@oss.nxp.com
commit 910efa649076be9c2e1326059830327cf4228cf6 upstream.
Currently, if streamon/streamoff calls are imbalanced we can either end up with a negative ISI m2m usage_count (if streamoff() is called more times than streamon()) in which case we'll not be able to restart the ISI pipe next time, or the usage_count never gets to 0 and the pipe is never switched off.
To avoid that, add a 'streaming' flag to mxc_isi_m2m_ctx_queue_data and use it in the streamon/streamoff to avoid incrementing/decrementing the usage_count uselessly, if called multiple times from the same context.
Fixes: cf21f328fcafac ("media: nxp: Add i.MX8 ISI driver") Cc: stable@vger.kernel.org Suggested-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Signed-off-by: Laurentiu Palcu laurentiu.palcu@oss.nxp.com Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Link: https://lore.kernel.org/r/20241023085643.978729-1-laurentiu.palcu@oss.nxp.co... Signed-off-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Signed-off-by: Mauro Carvalho Chehab mchehab+huawei@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-)
--- a/drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c +++ b/drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c @@ -43,6 +43,7 @@ struct mxc_isi_m2m_ctx_queue_data { struct v4l2_pix_format_mplane format; const struct mxc_isi_format_info *info; u32 sequence; + bool streaming; };
struct mxc_isi_m2m_ctx { @@ -486,15 +487,18 @@ static int mxc_isi_m2m_streamon(struct f enum v4l2_buf_type type) { struct mxc_isi_m2m_ctx *ctx = to_isi_m2m_ctx(fh); + struct mxc_isi_m2m_ctx_queue_data *q = mxc_isi_m2m_ctx_qdata(ctx, type); const struct v4l2_pix_format_mplane *out_pix = &ctx->queues.out.format; const struct v4l2_pix_format_mplane *cap_pix = &ctx->queues.cap.format; const struct mxc_isi_format_info *cap_info = ctx->queues.cap.info; const struct mxc_isi_format_info *out_info = ctx->queues.out.info; struct mxc_isi_m2m *m2m = ctx->m2m; bool bypass; - int ret;
+ if (q->streaming) + return 0; + mutex_lock(&m2m->lock);
if (m2m->usage_count == INT_MAX) { @@ -547,6 +551,8 @@ static int mxc_isi_m2m_streamon(struct f goto unchain; }
+ q->streaming = true; + return 0;
unchain: @@ -569,10 +575,14 @@ static int mxc_isi_m2m_streamoff(struct enum v4l2_buf_type type) { struct mxc_isi_m2m_ctx *ctx = to_isi_m2m_ctx(fh); + struct mxc_isi_m2m_ctx_queue_data *q = mxc_isi_m2m_ctx_qdata(ctx, type); struct mxc_isi_m2m *m2m = ctx->m2m;
v4l2_m2m_ioctl_streamoff(file, fh, type);
+ if (!q->streaming) + return 0; + mutex_lock(&m2m->lock);
/* @@ -598,6 +608,8 @@ static int mxc_isi_m2m_streamoff(struct
mutex_unlock(&m2m->lock);
+ q->streaming = false; + return 0; }