Re: v4.16-rc1 misaligned atomics in skb__clone / __napi_alloc_skb
From: Eric Dumazet <hidden>
Date: 2018-02-15 17:43:15
Also in:
lkml
Subsystem:
networking drivers, the rest, tun/tap driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Willem de Bruijn, Jason Wang
On Thu, 2018-02-15 at 09:24 -0800, Eric Dumazet wrote:
I will send something more suited to original intent of these commits : 90e33d45940793def6f773b2d528e9f3c84ffdc7 tun: enable napi_gro_frags() for TUN/TAP driver 943170998b200190f99d3fe7e771437e2c51f319 tun: enable NAPI for TUN/TAP driver
Can you try this patch ? Thanks ! drivers/net/tun.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-)
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 81e6cc951e7fc7c983919365c34842c34bcaedcf..b52258c327d2e1d7c7476de345e49f082909c246 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c@@ -1489,27 +1489,23 @@ static struct sk_buff *tun_napi_alloc_frags(struct tun_file *tfile, skb->truesize += skb->data_len; for (i = 1; i < it->nr_segs; i++) { + struct page_frag *pfrag = ¤t->task_frag; size_t fragsz = it->iov[i].iov_len; - unsigned long offset; - struct page *page; - void *data; if (fragsz == 0 || fragsz > PAGE_SIZE) { err = -EINVAL; goto free; } - local_bh_disable(); - data = napi_alloc_frag(fragsz); - local_bh_enable(); - if (!data) { + if (!skb_page_frag_refill(fragsz, pfrag, GFP_KERNEL)) { err = -ENOMEM; goto free; } - page = virt_to_head_page(data); - offset = data - page_address(page); - skb_fill_page_desc(skb, i - 1, page, offset, fragsz); + skb_fill_page_desc(skb, i - 1, pfrag->page, + pfrag->offset, fragsz); + page_ref_inc(pfrag->page); + pfrag->offset += fragsz; } return skb;