During the aborting of a command, the software receives a command completion event for the command ring stopped, with the TRB pointing to the next TRB after the aborted command.

If the command we abort is located just before the Link TRB in the command ring, then during the 'command ring stopped' completion event, the xHC gives the Link TRB in the event's cmd DMA, which causes a mismatch in handling command completion event.

To address this situation, move the 'command ring stopped' completion event check slightly earlier, since the specific command it stopped on isn't of significant concern.

Fixes: 7f84eef0dafb ("USB: xhci: No-op command queueing and irq handler.") Cc: stable@vger.kernel.org Signed-off-by: Faisal Hassan quic_faisalh@quicinc.com ---

Changes in v3: - Skip dma check for the cmd ring stopped event - v2 link: https://lore.kernel.org/all/20241021131904.20678-1-quic_faisalh@quicinc.com

Changes in v2: - Added Fixes tag - Removed traversing of TRBs with in_range() API. - Simplified the if condition check. - v1 link: https://lore.kernel.org/all/20241018195953.12315-1-quic_faisalh@quicinc.com

drivers/usb/host/xhci-ring.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index b2950c35c740..1ffc69c48eac 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1718,6 +1718,14 @@ static void handle_cmd_completion(struct xhci_hcd *xhci,

trace_xhci_handle_command(xhci->cmd_ring, &cmd_trb->generic);

+ cmd_comp_code = GET_COMP_CODE(le32_to_cpu(event->status)); + + /* If CMD ring stopped we own the trbs between enqueue and dequeue */ + if (cmd_comp_code == COMP_COMMAND_RING_STOPPED) { + complete_all(&xhci->cmd_ring_stop_completion); + return; + } + cmd_dequeue_dma = xhci_trb_virt_to_dma(xhci->cmd_ring->deq_seg, cmd_trb); /* @@ -1734,14 +1742,6 @@ static void handle_cmd_completion(struct xhci_hcd *xhci,

cancel_delayed_work(&xhci->cmd_timer);

- cmd_comp_code = GET_COMP_CODE(le32_to_cpu(event->status)); - - /* If CMD ring stopped we own the trbs between enqueue and dequeue */ - if (cmd_comp_code == COMP_COMMAND_RING_STOPPED) { - complete_all(&xhci->cmd_ring_stop_completion); - return; - } - if (cmd->command_trb != xhci->cmd_ring->dequeue) { xhci_err(xhci, "Command completion event does not match command\n");