Commit 1f090494 authored by Larysa Zaremba's avatar Larysa Zaremba Committed by Jakub Kicinski
Browse files

ice: xsk: Fix cleaning of XDP_TX frames 



Incrementation of xsk_frames inside the for-loop produces
infinite loop, if we have both normal AF_XDP-TX and XDP_TXed
buffers to complete.

Split xsk_frames into 2 variables (xsk_frames and completed_frames)
to eliminate this bug.

Fixes: 29322791 ("ice: xsk: change batched Tx descriptor cleaning")
Acked-by: default avatarMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: default avatarLarysa Zaremba <larysa.zaremba@intel.com>
Reviewed-by: default avatarAlexander Duyck <alexanderduyck@fb.com>
Acked-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
Link: https://lore.kernel.org/r/20230209160130.1779890-1-larysa.zaremba@intel.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent ee059170

drivers/net/ethernet/intel/ice/ice_xsk.c

+9 −6
Original line number Diff line number Diff line
@@ -800,6 +800,7 @@ static void ice_clean_xdp_irq_zc(struct ice_tx_ring *xdp_ring) 
	struct ice_tx_desc *tx_desc;

	u16 cnt = xdp_ring->count;

	struct ice_tx_buf *tx_buf;

	u16 completed_frames = 0;

	u16 xsk_frames = 0;

	u16 last_rs;

	int i;
@@ -809,19 +810,21 @@ static void ice_clean_xdp_irq_zc(struct ice_tx_ring *xdp_ring) 
	if ((tx_desc->cmd_type_offset_bsz &

	    cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE))) {

		if (last_rs >= ntc)

			xsk_frames = last_rs - ntc + 1;

			completed_frames = last_rs - ntc + 1;

		else

			xsk_frames = last_rs + cnt - ntc + 1;

			completed_frames = last_rs + cnt - ntc + 1;

	}



	if (!xsk_frames)

	if (!completed_frames)

		return;



	if (likely(!xdp_ring->xdp_tx_active))

	if (likely(!xdp_ring->xdp_tx_active)) {

		xsk_frames = completed_frames;

		goto skip;

	}



	ntc = xdp_ring->next_to_clean;

	for (i = 0; i < xsk_frames; i++) {

	for (i = 0; i < completed_frames; i++) {

		tx_buf = &xdp_ring->tx_buf[ntc];



		if (tx_buf->raw_buf) {
@@ -837,7 +840,7 @@ static void ice_clean_xdp_irq_zc(struct ice_tx_ring *xdp_ring) 
	}

skip:

	tx_desc->cmd_type_offset_bsz = 0;

	xdp_ring->next_to_clean += xsk_frames;

	xdp_ring->next_to_clean += completed_frames;

	if (xdp_ring->next_to_clean >= cnt)

		xdp_ring->next_to_clean -= cnt;

	if (xsk_frames)