On 11/23/20 6:56 PM, Björn Töpel wrote:
From: Björn Töpel <bjorn.to...@intel.com>Commit 642e450b6b59 ("xsk: Do not discard packet when NETDEV_TX_BUSY") addressed the problem that packets were discarded from the Tx AF_XDP ring, when the driver returned NETDEV_TX_BUSY. Part of the fix was bumping the skbuff reference count, so that the buffer would not be freed by dev_direct_xmit(). A reference count larger than one means that the skbuff is "shared", which is not the case. If the "shared" skbuff is sent to the generic XDP receive path, netif_receive_generic_xdp(), and pskb_expand_head() is entered the BUG_ON(skb_shared(skb)) will trigger. This patch adds a variant to dev_direct_xmit(), __dev_direct_xmit(), where a user can select the skbuff free policy. This allows AF_XDP to avoid bumping the reference count, but still keep the NETDEV_TX_BUSY behavior. Reported-by: Yonghong Song <y...@fb.com> Fixes: 642e450b6b59 ("xsk: Do not discard packet when NETDEV_TX_BUSY") Signed-off-by: Björn Töpel <bjorn.to...@intel.com>
Yeah looks better! Applied, thanks!
