diff options
| author | Wei Fang <wei.fang@nxp.com> | 2025-12-04 15:13:32 +0800 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2025-12-29 17:35:36 +0100 |
| commit | a48e232210009be50591fdea8ba7c07b0f566a13 (patch) | |
| tree | 5b7023fbd78d0de5022601e42310a4bddd007d4e | |
| parent | a6694b7e39b34757c045c4dc499fb2b8a635bce0 (diff) | |
net: stmmac: fix the crash issue for zero copy XDP_TX action
There is a crash issue when running zero copy XDP_TX action, the crash
log is shown below.
[ 216.122464] Unable to handle kernel paging request at virtual address fffeffff80000000
[ 216.187524] Internal error: Oops: 0000000096000144 [#1] SMP
[ 216.301694] Call trace:
[ 216.304130] dcache_clean_poc+0x20/0x38 (P)
[ 216.308308] __dma_sync_single_for_device+0x1bc/0x1e0
[ 216.313351] stmmac_xdp_xmit_xdpf+0x354/0x400
[ 216.317701] __stmmac_xdp_run_prog+0x164/0x368
[ 216.322139] stmmac_napi_poll_rxtx+0xba8/0xf00
[ 216.326576] __napi_poll+0x40/0x218
[ 216.408054] Kernel panic - not syncing: Oops: Fatal exception in interrupt
For XDP_TX action, the xdp_buff is converted to xdp_frame by
xdp_convert_buff_to_frame(). The memory type of the resulting xdp_frame
depends on the memory type of the xdp_buff. For page pool based xdp_buff
it produces xdp_frame with memory type MEM_TYPE_PAGE_POOL. For zero copy
XSK pool based xdp_buff it produces xdp_frame with memory type
MEM_TYPE_PAGE_ORDER0. However, stmmac_xdp_xmit_back() does not check the
memory type and always uses the page pool type, this leads to invalid
mappings and causes the crash. Therefore, check the xdp_buff memory type
in stmmac_xdp_xmit_back() to fix this issue.
Fixes: bba2556efad6 ("net: stmmac: Enable RX via AF_XDP zero-copy")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Hariprasad Kelam <hkelam@marvell.com>
Link: https://patch.msgid.link/20251204071332.1907111-1-wei.fang@nxp.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
| -rw-r--r-- | drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index da206b24aaed..b3730312aeed 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -89,6 +89,7 @@ MODULE_PARM_DESC(phyaddr, "Physical device address"); #define STMMAC_XDP_CONSUMED BIT(0) #define STMMAC_XDP_TX BIT(1) #define STMMAC_XDP_REDIRECT BIT(2) +#define STMMAC_XSK_CONSUMED BIT(3) static int flow_ctrl = 0xdead; module_param(flow_ctrl, int, 0644); @@ -5126,6 +5127,7 @@ static int stmmac_xdp_get_tx_queue(struct stmmac_priv *priv, static int stmmac_xdp_xmit_back(struct stmmac_priv *priv, struct xdp_buff *xdp) { + bool zc = !!(xdp->rxq->mem.type == MEM_TYPE_XSK_BUFF_POOL); struct xdp_frame *xdpf = xdp_convert_buff_to_frame(xdp); int cpu = smp_processor_id(); struct netdev_queue *nq; @@ -5142,9 +5144,18 @@ static int stmmac_xdp_xmit_back(struct stmmac_priv *priv, /* Avoids TX time-out as we are sharing with slow path */ txq_trans_cond_update(nq); - res = stmmac_xdp_xmit_xdpf(priv, queue, xdpf, false); - if (res == STMMAC_XDP_TX) + /* For zero copy XDP_TX action, dma_map is true */ + res = stmmac_xdp_xmit_xdpf(priv, queue, xdpf, zc); + if (res == STMMAC_XDP_TX) { stmmac_flush_tx_descriptors(priv, queue); + } else if (res == STMMAC_XDP_CONSUMED && zc) { + /* xdp has been freed by xdp_convert_buff_to_frame(), + * no need to call xsk_buff_free() again, so return + * STMMAC_XSK_CONSUMED. + */ + res = STMMAC_XSK_CONSUMED; + xdp_return_frame(xdpf); + } __netif_tx_unlock(nq); @@ -5494,6 +5505,8 @@ read_again: break; case STMMAC_XDP_CONSUMED: xsk_buff_free(buf->xdp); + fallthrough; + case STMMAC_XSK_CONSUMED: rx_dropped++; break; case STMMAC_XDP_TX: |