From 6ab57a6b80be45372d7f3dd58e9776549d0ce9cf Mon Sep 17 00:00:00 2001 From: Peter Crosthwaite Date: Mon, 26 May 2014 01:37:47 -0700 Subject: [PATCH] net: cadence_gem: Fix Tx descriptor update The local variable "desc" was being used to read-modify-write the first descriptor (of a multi-desc packet) upon packet completion. desc however continues to be used by the code as the current descriptor. Give this first desc RMW it's own local variable to avoid trampling. Signed-off-by: Peter Crosthwaite Signed-off-by: Michael Tokarev --- hw/net/cadence_gem.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/hw/net/cadence_gem.c b/hw/net/cadence_gem.c index a26861e2ae..5335db874f 100644 --- a/hw/net/cadence_gem.c +++ b/hw/net/cadence_gem.c @@ -911,14 +911,16 @@ static void gem_transmit(GemState *s) /* Last descriptor for this packet; hand the whole thing off */ if (tx_desc_get_last(desc)) { + unsigned desc_first[2]; + /* Modify the 1st descriptor of this packet to be owned by * the processor. */ - cpu_physical_memory_read(s->tx_desc_addr, - (uint8_t *)&desc[0], sizeof(desc)); - tx_desc_set_used(desc); - cpu_physical_memory_write(s->tx_desc_addr, - (uint8_t *)&desc[0], sizeof(desc)); + cpu_physical_memory_read(s->tx_desc_addr, (uint8_t *)desc_first, + sizeof(desc_first)); + tx_desc_set_used(desc_first); + cpu_physical_memory_write(s->tx_desc_addr, (uint8_t *)desc_first, + sizeof(desc_first)); /* Advance the hardare current descriptor past this packet */ if (tx_desc_get_wrap(desc)) { s->tx_desc_addr = s->regs[GEM_TXQBASE]; -- GitLab