Real HW always treats RX ring with RDH == RDT as empty. Emulation is supposed to behave the same.
Reported-by: Chris Webb <chris.w...@elastichosts.com> Reported-by: Richard Davies <richard.dav...@elastichosts.com> Signed-off-by: Dmitry Fleytman <dmi...@daynix.com> --- hw/e1000.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/hw/e1000.c b/hw/e1000.c index 63fee10..ab39d47 100644 --- a/hw/e1000.c +++ b/hw/e1000.c @@ -92,7 +92,6 @@ typedef struct E1000State_st { uint32_t rxbuf_size; uint32_t rxbuf_min_shift; - int check_rxov; struct e1000_tx { unsigned char header[256]; unsigned char vlan_header[4]; @@ -741,11 +740,11 @@ static bool e1000_has_rxbufs(E1000State *s, size_t total_size) int bufs; /* Fast-path short packets */ if (total_size <= s->rxbuf_size) { - return s->mac_reg[RDH] != s->mac_reg[RDT] || !s->check_rxov; + return s->mac_reg[RDH] != s->mac_reg[RDT]; } if (s->mac_reg[RDH] < s->mac_reg[RDT]) { bufs = s->mac_reg[RDT] - s->mac_reg[RDH]; - } else if (s->mac_reg[RDH] > s->mac_reg[RDT] || !s->check_rxov) { + } else if (s->mac_reg[RDH] > s->mac_reg[RDT]) { bufs = s->mac_reg[RDLEN] / sizeof(struct e1000_rx_desc) + s->mac_reg[RDT] - s->mac_reg[RDH]; } else { @@ -848,7 +847,6 @@ e1000_receive(NetClientState *nc, const uint8_t *buf, size_t size) if (++s->mac_reg[RDH] * sizeof(desc) >= s->mac_reg[RDLEN]) s->mac_reg[RDH] = 0; - s->check_rxov = 1; /* see comment in start_xmit; same here */ if (s->mac_reg[RDH] == rdh_start) { DBGOUT(RXERR, "RDH wraparound @%x, RDT %x, RDLEN %x\n", @@ -925,7 +923,6 @@ mac_writereg(E1000State *s, int index, uint32_t val) static void set_rdt(E1000State *s, int index, uint32_t val) { - s->check_rxov = 0; s->mac_reg[index] = val & 0xffff; if (e1000_has_rxbufs(s, 1)) { qemu_flush_queued_packets(&s->nic->nc); -- 1.7.11.4