diff options
| author | Björn Töpel <bjorn.topel@intel.com> | 2018-05-22 09:35:01 +0200 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2018-05-22 10:25:06 +0200 |
| commit | 37b076933a8e38e72ffd3c40d3eeb5949f38baf3 (patch) | |
| tree | d69135d54b4a1036d34377ddc40255b4d22ae49a | |
| parent | 1c4917da36ed76981cc3c2671b3a44765c02bbc3 (diff) | |
xsk: add missing write- and data-dependency barrier
Here, we add a missing write-barrier, and use READ_ONCE for the
data-dependency barrier.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| -rw-r--r-- | net/xdp/xsk.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 378dd9287da5..01f010ec0c05 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -228,6 +228,8 @@ static int xsk_init_queue(u32 entries, struct xsk_queue **queue, if (!q) return -ENOMEM; + /* Make sure queue is ready before it can be seen by others */ + smp_wmb(); *queue = q; return 0; } @@ -532,21 +534,23 @@ static int xsk_mmap(struct file *file, struct socket *sock, unsigned long size = vma->vm_end - vma->vm_start; struct xdp_sock *xs = xdp_sk(sock->sk); struct xsk_queue *q = NULL; + struct xdp_umem *umem; unsigned long pfn; struct page *qpg; if (offset == XDP_PGOFF_RX_RING) { - q = xs->rx; + q = READ_ONCE(xs->rx); } else if (offset == XDP_PGOFF_TX_RING) { - q = xs->tx; + q = READ_ONCE(xs->tx); } else { - if (!xs->umem) + umem = READ_ONCE(xs->umem); + if (!umem) return -EINVAL; if (offset == XDP_UMEM_PGOFF_FILL_RING) - q = xs->umem->fq; + q = READ_ONCE(umem->fq); else if (offset == XDP_UMEM_PGOFF_COMPLETION_RING) - q = xs->umem->cq; + q = READ_ONCE(umem->cq); } if (!q) |