diff options
| author | Michal Kubeček <mkubecek@suse.cz> | 2012-09-14 04:59:52 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-09-19 16:07:58 -0400 |
| commit | 15c041759bfcd9ab0a4e43f1c16e2644977d0467 (patch) | |
| tree | c530b3395136fc4c29ff022200adf5d948ce5bc8 /mm/backing-dev.c | |
| parent | dbd6b11e15a2f96030da17dbeda943a8a98ee990 (diff) | |
tcp: flush DMA queue before sk_wait_data if rcv_wnd is zero
If recv() syscall is called for a TCP socket so that
- IOAT DMA is used
- MSG_WAITALL flag is used
- requested length is bigger than sk_rcvbuf
- enough data has already arrived to bring rcv_wnd to zero
then when tcp_recvmsg() gets to calling sk_wait_data(), receive
window can be still zero while sk_async_wait_queue exhausts
enough space to keep it zero. As this queue isn't cleaned until
the tcp_service_net_dma() call, sk_wait_data() cannot receive
any data and blocks forever.
If zero receive window and non-empty sk_async_wait_queue is
detected before calling sk_wait_data(), process the queue first.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'mm/backing-dev.c')
0 files changed, 0 insertions, 0 deletions