This is a note to let you know that I've just added the patch titled xhci: Prevent infinite loop in transaction errors recovery for streams to the 6.1-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: xhci-prevent-infinite-loop-in-transaction-errors-recovery-for-streams.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From a1575120972ecd7baa6af6a69e4e7ea9213bde7c Mon Sep 17 00:00:00 2001 From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> Date: Wed, 30 Nov 2022 11:19:43 +0200 Subject: xhci: Prevent infinite loop in transaction errors recovery for streams From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> commit a1575120972ecd7baa6af6a69e4e7ea9213bde7c upstream. Make sure to also limit the amount of soft reset retries for transaction errors on streams in cases where the transaction error event doesn't point to any specific TRB. In these cases we don't know the TRB or stream ring, but we do know which endpoint had the error. To keep error counting simple and functional, move the current err_count from ring structure to endpoint structure. Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20221130091944.2171610-6-mathias.nyman@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/host/xhci-ring.c | 14 ++++++++++---- drivers/usb/host/xhci.h | 2 +- 2 files changed, 11 insertions(+), 5 deletions(-) --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -2458,7 +2458,7 @@ static int process_bulk_intr_td(struct x switch (trb_comp_code) { case COMP_SUCCESS: - ep_ring->err_count = 0; + ep->err_count = 0; /* handle success with untransferred data as short packet */ if (ep_trb != td->last_trb || remaining) { xhci_warn(xhci, "WARN Successful completion on short TX\n"); @@ -2484,7 +2484,7 @@ static int process_bulk_intr_td(struct x break; case COMP_USB_TRANSACTION_ERROR: if (xhci->quirks & XHCI_NO_SOFT_RETRY || - (ep_ring->err_count++ > MAX_SOFT_RETRY) || + (ep->err_count++ > MAX_SOFT_RETRY) || le32_to_cpu(slot_ctx->tt_info) & TT_SLOT) break; @@ -2565,8 +2565,14 @@ static int handle_tx_event(struct xhci_h case COMP_USB_TRANSACTION_ERROR: case COMP_INVALID_STREAM_TYPE_ERROR: case COMP_INVALID_STREAM_ID_ERROR: - xhci_handle_halted_endpoint(xhci, ep, 0, NULL, - EP_SOFT_RESET); + xhci_dbg(xhci, "Stream transaction error ep %u no id\n", + ep_index); + if (ep->err_count++ > MAX_SOFT_RETRY) + xhci_handle_halted_endpoint(xhci, ep, 0, NULL, + EP_HARD_RESET); + else + xhci_handle_halted_endpoint(xhci, ep, 0, NULL, + EP_SOFT_RESET); goto cleanup; case COMP_RING_UNDERRUN: case COMP_RING_OVERRUN: --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -933,6 +933,7 @@ struct xhci_virt_ep { * have to restore the device state to the previous state */ struct xhci_ring *new_ring; + unsigned int err_count; unsigned int ep_state; #define SET_DEQ_PENDING (1 << 0) #define EP_HALTED (1 << 1) /* For stall handling */ @@ -1627,7 +1628,6 @@ struct xhci_ring { * if we own the TRB (if we are the consumer). See section 4.9.1. */ u32 cycle_state; - unsigned int err_count; unsigned int stream_id; unsigned int num_segs; unsigned int num_trbs_free; Patches currently in stable-queue which might be from mathias.nyman@xxxxxxxxxxxxxxx are queue-6.1/xhci-prevent-infinite-loop-in-transaction-errors-recovery-for-streams.patch