diff options
| author | Jakub Kicinski <kuba@kernel.org> | 2026-10-27 16:49:37 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-10-29 08:49:31 -0700 |
| commit | 09f10efee6f93863ea71489ce84563f4d51787f6 (patch) | |
| tree | ad8fbc3bb9ff5657a68114123245f19ceb235921 /drivers | |
| parent | db2c610df81e34d497f49b68a0a1681c3f203bdb (diff) | |
eth: bnxt: resize Rx head buffers when rx-copybreak changes
Since rx-copybreak became configurable, bnxt_set_ring_params() sizes
the head buffers to fit at least rx_copybreak bytes, and the copybreak
path in bnxt_copy_data() syncs rx_copybreak bytes of the head buffer.
bnxt_set_tunable() however only updates bp->rx_copybreak, and nothing
on the open path recalculates the ring parameters. After raising
rx-copybreak the head buffers keep their old size until some other
setting changes, and bnxt_copy_data() syncs past their end, into the
next buffer in the page or past the end of the page:
DMA-API: bnxt_en 0000:01:00.0: device driver tries to sync DMA memory it has not allocated [device address=0x00000002aa210c40] [size=1024 bytes]
WARNING: kernel/dma/debug.c:1162 at check_sync+0x577/0x1eb0, CPU#22: swapper/22/0
Call Trace:
<IRQ>
debug_dma_sync_single_for_cpu+0x66/0x90
bnxt_copy_data+0x12f/0x290
bnxt_rx_pkt+0x24ea/0x50f0
__bnxt_poll_work+0x42c/0xc00
bnxt_poll_p5+0x579/0x17a0
__napi_poll+0x8b/0x2c0
net_rx_action+0x58f/0xbb0
Here the head buffers were still sized for the 640B HDS threshold,
four 1kB buffers per page, while rx-copybreak was raised to 1024.
Without coherent DMA or with swiotlb the oversized sync can corrupt
a neighboring buffer owned by the device or by an skb.
The device must be down for rx-copybreak to change, so recalculate the
ring parameters right away, like bnxt_set_ringparam() does.
Hit while testing patch 1, tested on BCM57504 - boot; set rx-copybreak
to 1024 with the link down (CONFIG_DMA_API_DEBUG); ifup.
Fixes: 152f4da05aee ("bnxt_en: add support for rx-copybreak ethtool command")
Reviewed-by: Michael Chan <michael.chan@broadcom.com>
Link: https://patch.msgid.link/20261027234940.1267225-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c index 622e89587e5d..ef4bea4a0f8c 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c @@ -4601,6 +4601,7 @@ static int bnxt_set_tunable(struct net_device *dev, if (netif_running(dev)) return -EBUSY; bp->rx_copybreak = rx_copybreak; + bnxt_set_ring_params(bp); } return 0; case ETHTOOL_PFC_PREVENTION_TOUT: |