gdbserver: Handle 'v' packet while processing qSymbol.

On powerpc64, qSymbol query may require gdb to read a function
descriptor, sending a vFile packet to gdbserver.  Thus, we need
to handle 'v' packet in look_up_one_symbol.

vFile replies may be quite long, and require reallocating own_buf.
Since handle_v_requests assumes the buffer is the static global own_buf
from server.c and reallocates it, we need to make own_buf global and
use it from look_up_one_symbol instead of using our own auto variable.
I've also done the same change in relocate_instruction, just in case.

On gdb side, in remote_check_symbols, rs->buf may be clobbered by vFile
handling, yet we need its contents for the reply (the symbol name is
stored there).  Allocate a new buffer instead.

This broke fast tracepoints on powerpc64, due to errors in reading IPA
symbols.

gdb/ChangeLog:

	* remote.c (remote_check_symbols): Allocate own buffer for reply.

gdbserver/ChangeLog:

	* remote-utils.c (look_up_one_symbol): Remove own_buf, handle 'v'
	packets.
	(relocate_instruction): Remove own_buf.
	* server.c (own_buf): Make global.
	(handle_v_requests): Make global.
	* server.h (own_buf): New declaration.
	(handle_v_requests): New prototype.

1 files changed, 7 insertions, 5 deletions

diff --git a/gdb/remote.c b/gdb/remote.c
index af0a08a..5c407b6 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -4335,6 +4335,7 @@ remote_check_symbols (void)
   struct remote_state *rs = get_remote_state ();
   char *msg, *reply, *tmp;
   int end;
+  long reply_size;
   struct cleanup *old_chain;
 
   /* The remote side has no concept of inferiors that aren't running
@@ -4356,13 +4357,15 @@ remote_check_symbols (void)
      because we need both at the same time.  */
   msg = (char *) xmalloc (get_remote_packet_size ());
   old_chain = make_cleanup (xfree, msg);
+  reply = (char *) xmalloc (get_remote_packet_size ());
+  make_cleanup (free_current_contents, &reply);
+  reply_size = get_remote_packet_size ();
 
   /* Invite target to request symbol lookups.  */
 
   putpkt ("qSymbol::");
-  getpkt (&rs->buf, &rs->buf_size, 0);
-  packet_ok (rs->buf, &remote_protocol_packets[PACKET_qSymbol]);
-  reply = rs->buf;
+  getpkt (&reply, &reply_size, 0);
+  packet_ok (reply, &remote_protocol_packets[PACKET_qSymbol]);
 
   while (startswith (reply, "qSymbol:"))
     {
@@ -4390,8 +4393,7 @@ remote_check_symbols (void)
 	}
   
       putpkt (msg);
-      getpkt (&rs->buf, &rs->buf_size, 0);
-      reply = rs->buf;
+      getpkt (&reply, &reply_size, 0);
     }
 
   do_cleanups (old_chain);