diff options
| author | Peter Crosthwaite <peter.crosthwaite@xilinx.com> | 2013-12-03 22:02:03 -0800 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2013-12-10 13:28:50 +0000 |
| commit | 8202aa539135a44906c38f82a469234ec65e0ef7 (patch) | |
| tree | 17175bd95b4210a6b10e1a04b04de5086d4cc3c0 /hw/net | |
| parent | 3ae5725f86a82751cccf6bc075e5ebfb327ac283 (diff) | |
net/cadence_gem: Don't rx packets when no rx buffer available
Return false from can_receive() when no valid buffer descriptor is
available. Ensures against mass packet droppage in some applications.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: cde00ef774e84e2586bf10fd37b542f75bf36cfb.1386136219.git.peter.crosthwaite@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'hw/net')
| -rw-r--r-- | hw/net/cadence_gem.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/hw/net/cadence_gem.c b/hw/net/cadence_gem.c index f6e38cacfc..92dc2f21fa 100644 --- a/hw/net/cadence_gem.c +++ b/hw/net/cadence_gem.c @@ -463,6 +463,15 @@ static int gem_can_receive(NetClientState *nc) return 0; } + if (rx_desc_get_ownership(s->rx_desc) == 1) { + if (s->can_rx_state != 2) { + s->can_rx_state = 2; + DB_PRINT("can't receive - busy buffer descriptor 0x%x\n", + s->rx_desc_addr); + } + return 0; + } + if (s->can_rx_state != 0) { s->can_rx_state = 0; DB_PRINT("can receive 0x%x\n", s->rx_desc_addr); @@ -1142,7 +1151,7 @@ static void gem_write(void *opaque, hwaddr offset, uint64_t val, /* Reset to start of Q when transmit disabled. */ s->tx_desc_addr = s->regs[GEM_TXQBASE]; } - if (val & GEM_NWCTRL_RXENA) { + if (gem_can_receive(qemu_get_queue(s->nic))) { qemu_flush_queued_packets(qemu_get_queue(s->nic)); } break; |