From 38a1d0fe3f92c74d848a8665d8d43392bc23bbfc Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Wed, 15 Apr 2009 17:16:31 +0100 Subject: [PATCH] [gdb] Allow resynchronisation with gdb This replaces the gdbstub's polite NAK behavior with retransmission of the current outstanding reply packet. It solves situations where gdb and gPXE's gdbstub get out of sync due to the lack of flow control in the gdb protocol spec. Signed-off-by: Michael Brown --- src/core/gdbstub.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/src/core/gdbstub.c b/src/core/gdbstub.c index 45df7f2b..c8083955 100644 --- a/src/core/gdbstub.c +++ b/src/core/gdbstub.c @@ -344,12 +344,10 @@ static void gdbstub_state_cksum2 ( struct gdbstub *stub, char ch ) { static void gdbstub_state_wait_ack ( struct gdbstub *stub, char ch ) { if ( ch == '+' ) { stub->parse = gdbstub_state_new; - } else if ( ch == '-' ) { - gdbstub_tx_packet ( stub ); /* retransmit */ - } else if ( ch == '$' ) { - /* GDB is reconnecting, drop our packet and listen to GDB */ - stub->trans->send ( "-", 1 ); - stub->parse = gdbstub_state_new; + } else { + /* This retransmit is very aggressive but necessary to keep + * in sync with GDB. */ + gdbstub_tx_packet ( stub ); } }