This is a note to let you know that I've just added the patch titled
media: ti: j721e-csi2rx: Fix races while restarting DMA
to the 6.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
media-ti-j721e-csi2rx-fix-races-while-restarting-dma.patch
and it can be found in the queue-6.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 310d7ea439d5dde8455ce858be7e8f1cfb6833a7
Author: Jai Luthra <j-luthra@xxxxxx>
Date: Fri Feb 23 13:53:02 2024 +0530
media: ti: j721e-csi2rx: Fix races while restarting DMA
[ Upstream commit ad79c9ecea5baa7b4f19677e4b1c881ed89b0c3b ]
After the frame is submitted to DMA, it may happen that the submitted
list is not updated soon enough, and the DMA callback is triggered
before that.
This can lead to kernel crashes, so move everything in a single
lock/unlock section to prevent such races.
Fixes: b4a3d877dc92 ("media: ti: Add CSI2RX support for J721E")
Signed-off-by: Jai Luthra <j-luthra@xxxxxx>
Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
index 59b30fc431440..c8c1fda73e530 100644
--- a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
+++ b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
@@ -762,15 +762,14 @@ static void ti_csi2rx_buffer_queue(struct vb2_buffer *vb)
dev_warn(csi->dev,
"Failed to drain DMA. Next frame might be bogus\n");
+ spin_lock_irqsave(&dma->lock, flags);
ret = ti_csi2rx_start_dma(csi, buf);
if (ret) {
- dev_err(csi->dev, "Failed to start DMA: %d\n", ret);
- spin_lock_irqsave(&dma->lock, flags);
vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
dma->state = TI_CSI2RX_DMA_IDLE;
spin_unlock_irqrestore(&dma->lock, flags);
+ dev_err(csi->dev, "Failed to start DMA: %d\n", ret);
} else {
- spin_lock_irqsave(&dma->lock, flags);
list_add_tail(&buf->list, &dma->submitted);
spin_unlock_irqrestore(&dma->lock, flags);
}
