[PATCH] thunderbolt: stream: Undo more if the start fails

[PATCH] thunderbolt: stream: Undo more if the start fails

[Greg Kroah-Hartman]

From: Josef Bacik <josef@toxicpanda.com>

If the receive buffers cannot be allocated or mapped,
tbstream_dev_start() stops and frees the rings, but

 - leaves the DMA paths through the XDomain connection enabled, with the
   hop IDs of rings which no longer exist;
 - does not release the frame array and the pages which
   tbstream_dev_alloc_rx_buffers() had allocated and mapped before it
   failed.

Fixes: 6db21d817b43 ("thunderbolt: Add support for USB4STREAM")
Cc: stable <stable@kernel.org>
Cc: Andreas Noever <andreas.noever@gmail.com>
Cc: Mika Westerberg <westeri@kernel.org>
Cc: Yehezkel Bernat <YehezkelShB@gmail.com>
Cc: Alan Borzeszkowski <alan.borzeszkowski@linux.intel.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/thunderbolt/stream.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/thunderbolt/stream.c b/drivers/thunderbolt/stream.c
index 4f9a57b77bfa..c9e1987a6924 100644
--- a/drivers/thunderbolt/stream.c
+++ b/drivers/thunderbolt/stream.c
@@ -683,6 +683,12 @@ static int tbstream_dev_start(struct tbstream_dev *sdev)
 err_stop:
 	tb_ring_stop(sdev->rx_ring.ring);
 	tb_ring_stop(sdev->tx_ring.ring);
+	tb_xdomain_disable_paths(xd, sdev->out_hopid,
+				 sdev->tx_ring.ring->hop,
+				 sdev->in_hopid,
+				 sdev->rx_ring.ring->hop);
+	if (sdev->rx_ring.frames)
+		tbstream_ring_free(&sdev->rx_ring);
 err_free_rx:
 	tb_ring_free(sdev->rx_ring.ring);
 err_free_tx_buffers:
-- 
2.56.0

Re: [PATCH] thunderbolt: stream: Undo more if the start fails

[Mika Westerberg]

Hi,

On Tue, Oct 27, 2026 at 03:24:52PM +0100, Greg Kroah-Hartman wrote:
> From: Josef Bacik <josef@toxicpanda.com>
> 
> If the receive buffers cannot be allocated or mapped,
> tbstream_dev_start() stops and frees the rings, but
> 
>  - leaves the DMA paths through the XDomain connection enabled, with the
>    hop IDs of rings which no longer exist;
>  - does not release the frame array and the pages which
>    tbstream_dev_alloc_rx_buffers() had allocated and mapped before it
>    failed.
> 
> Fixes: 6db21d817b43 ("thunderbolt: Add support for USB4STREAM")
> Cc: stable <stable@kernel.org>
> Cc: Andreas Noever <andreas.noever@gmail.com>
> Cc: Mika Westerberg <westeri@kernel.org>

Do you want to take this directly via USB tree? Then,

Acked-by: Mika Westerberg (Intel) <westeri@kernel.org>

Re: [PATCH] thunderbolt: stream: Undo more if the start fails

[Greg Kroah-Hartman]

On Tue, Oct 27, 2026 at 03:33:25PM +0100, Mika Westerberg wrote:
> Hi,
> 
> On Tue, Oct 27, 2026 at 03:24:52PM +0100, Greg Kroah-Hartman wrote:
> > From: Josef Bacik <josef@toxicpanda.com>
> > 
> > If the receive buffers cannot be allocated or mapped,
> > tbstream_dev_start() stops and frees the rings, but
> > 
> >  - leaves the DMA paths through the XDomain connection enabled, with the
> >    hop IDs of rings which no longer exist;
> >  - does not release the frame array and the pages which
> >    tbstream_dev_alloc_rx_buffers() had allocated and mapped before it
> >    failed.
> > 
> > Fixes: 6db21d817b43 ("thunderbolt: Add support for USB4STREAM")
> > Cc: stable <stable@kernel.org>
> > Cc: Andreas Noever <andreas.noever@gmail.com>
> > Cc: Mika Westerberg <westeri@kernel.org>
> 
> Do you want to take this directly via USB tree? Then,
> 
> Acked-by: Mika Westerberg (Intel) <westeri@kernel.org>

I can, thanks!

greg k-h