The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 5e1c67abc9301d05130b7e267c204e7005503b33 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024120248-scuff-roster-854c@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 5e1c67abc9301d05130b7e267c204e7005503b33 Mon Sep 17 00:00:00 2001 From: Kuangyi Chiang ki.chiang65@gmail.com Date: Wed, 6 Nov 2024 12:14:45 +0200 Subject: [PATCH] xhci: Fix control transfer error on Etron xHCI host

Performing a stability stress test on a USB3.0 2.5G ethernet adapter results in errors like this:

[ 91.441469] r8152 2-3:1.0 eth3: get_registers -71 [ 91.458659] r8152 2-3:1.0 eth3: get_registers -71 [ 91.475911] r8152 2-3:1.0 eth3: get_registers -71 [ 91.493203] r8152 2-3:1.0 eth3: get_registers -71 [ 91.510421] r8152 2-3:1.0 eth3: get_registers -71

The r8152 driver will periodically issue lots of control-IN requests to access the status of ethernet adapter hardware registers during the test.

This happens when the xHCI driver enqueue a control TD (which cross over the Link TRB between two ring segments, as shown) in the endpoint zero's transfer ring. Seems the Etron xHCI host can not perform this TD correctly, causing the USB transfer error occurred, maybe the upper driver retry that control-IN request can solve problem, but not all drivers do this.

| | ------- | TRB | Setup Stage ------- | TRB | Link ------- ------- | TRB | Data Stage ------- | TRB | Status Stage ------- | |

To work around this, the xHCI driver should enqueue a No Op TRB if next available TRB is the Link TRB in the ring segment, this can prevent the Setup and Data Stage TRB to be breaked by the Link TRB.

Check if the XHCI_ETRON_HOST quirk flag is set before invoking the workaround in xhci_queue_ctrl_tx().

Fixes: d0e96f5a71a0 ("USB: xhci: Control transfer support.") Cc: stable@vger.kernel.org Signed-off-by: Kuangyi Chiang ki.chiang65@gmail.com Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Link: https://lore.kernel.org/r/20241106101459.775897-20-mathias.nyman@linux.intel... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index f62b243d0fc4..517df97ef496 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -3733,6 +3733,20 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags, if (!urb->setup_packet) return -EINVAL;

+ if ((xhci->quirks & XHCI_ETRON_HOST) && + urb->dev->speed >= USB_SPEED_SUPER) { + /* + * If next available TRB is the Link TRB in the ring segment then + * enqueue a No Op TRB, this can prevent the Setup and Data Stage + * TRB to be breaked by the Link TRB. + */ + if (trb_is_link(ep_ring->enqueue + 1)) { + field = TRB_TYPE(TRB_TR_NOOP) | ep_ring->cycle_state; + queue_trb(xhci, ep_ring, false, 0, 0, + TRB_INTR_TARGET(0), field); + } + } + /* 1 TRB for setup, 1 for status */ num_trbs = 2; /*