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| author | Ioana Ciornei <ioana.ciornei@nxp.com> | 2025-10-16 16:58:07 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-10-29 14:01:21 +0100 |
| commit | 3b76a8cea7fae555325ca8659c69cfa716a64798 (patch) | |
| tree | 2c53e37db9dc7e8461d891565a5673f288cf5be4 /drivers/net | |
| parent | a2f2062881b6d5534c941a7471a9005873f67ffe (diff) | |
| download | linux-3b76a8cea7fae555325ca8659c69cfa716a64798.tar.gz linux-3b76a8cea7fae555325ca8659c69cfa716a64798.tar.bz2 linux-3b76a8cea7fae555325ca8659c69cfa716a64798.zip | |
dpaa2-eth: fix the pointer passed to PTR_ALIGN on Tx path
[ Upstream commit 902e81e679d86846a2404630d349709ad9372d0d ]
The blamed commit increased the needed headroom to account for
alignment. This means that the size required to always align a Tx buffer
was added inside the dpaa2_eth_needed_headroom() function. By doing
that, a manual adjustment of the pointer passed to PTR_ALIGN() was no
longer correct since the 'buffer_start' variable was already pointing
to the start of the skb's memory.
The behavior of the dpaa2-eth driver without this patch was to drop
frames on Tx even when the headroom was matching the 128 bytes
necessary. Fix this by removing the manual adjust of 'buffer_start' from
the PTR_MODE call.
Closes: https://lore.kernel.org/netdev/70f0dcd9-1906-4d13-82df-7bbbbe7194c6@app.fastmail.com/T/#u
Fixes: f422abe3f23d ("dpaa2-eth: increase the needed headroom to account for alignment")
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Tested-by: Mathew McBride <matt@traverse.com.au>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20251016135807.360978-1-ioana.ciornei@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c index 0a1a7d94583b..d27f5a8e59dc 100644 --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c @@ -994,8 +994,7 @@ static int dpaa2_eth_build_single_fd(struct dpaa2_eth_priv *priv, dma_addr_t addr; buffer_start = skb->data - dpaa2_eth_needed_headroom(skb); - aligned_start = PTR_ALIGN(buffer_start - DPAA2_ETH_TX_BUF_ALIGN, - DPAA2_ETH_TX_BUF_ALIGN); + aligned_start = PTR_ALIGN(buffer_start, DPAA2_ETH_TX_BUF_ALIGN); if (aligned_start >= skb->head) buffer_start = aligned_start; else |