[src/trunk]: src/sys/arch/xen/xen Add more XENPRINTF() to xbdback_connect()

[bouyer <bouyer%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/854ac7757b6e
branches:  trunk
changeset: 790757:854ac7757b6e
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Sun Oct 20 11:37:11 2013 +0000

description:
Add more XENPRINTF() to xbdback_connect()
in xbdback_backend_changed(), fix memory leak.
Do not free an uninitialized pointer in xbdback_connect(). Should fix
 hypervisor or dom0 reboot when using windows PV drivers, as reported
 by several users on port-xen.

diffstat:

 sys/arch/xen/xen/xbdback_xenbus.c |  15 ++++++++++++---
 1 files changed, 12 insertions(+), 3 deletions(-)

diffs (92 lines):

diff -r c349628ebbb7 -r 854ac7757b6e sys/arch/xen/xen/xbdback_xenbus.c
--- a/sys/arch/xen/xen/xbdback_xenbus.c Sun Oct 20 09:30:41 2013 +0000
+++ b/sys/arch/xen/xen/xbdback_xenbus.c Sun Oct 20 11:37:11 2013 +0000
@@ -1,4 +1,4 @@
-/*      $NetBSD: xbdback_xenbus.c,v 1.57 2012/07/23 01:31:01 jym Exp $      */
+/*      $NetBSD: xbdback_xenbus.c,v 1.58 2013/10/20 11:37:11 bouyer Exp $      */
 
 /*
  * Copyright (c) 2006 Manuel Bouyer.
@@ -26,7 +26,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xbdback_xenbus.c,v 1.57 2012/07/23 01:31:01 jym Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xbdback_xenbus.c,v 1.58 2013/10/20 11:37:11 bouyer Exp $");
 
 #include <sys/atomic.h>
 #include <sys/buf.h>
@@ -530,6 +530,7 @@
        const char *proto;
        struct xenbus_device *xbusd = xbdi->xbdi_xbusd;
 
+       XENPRINTF(("xbdback %s: connect\n", xbusd->xbusd_path));
        /* read comunication informations */
        err = xenbus_read_ul(NULL, xbusd->xbusd_otherend,
            "ring-ref", &ring_ref, 10);
@@ -538,6 +539,7 @@
                    xbusd->xbusd_otherend);
                return -1;
        }
+       XENPRINTF(("xbdback %s: connect ring-ref %lu\n", xbusd->xbusd_path, ring_ref));
        err = xenbus_read_ul(NULL, xbusd->xbusd_otherend,
            "event-channel", &revtchn, 10);
        if (err) {
@@ -545,12 +547,15 @@
                    xbusd->xbusd_otherend);
                return -1;
        }
+       XENPRINTF(("xbdback %s: connect revtchn %lu\n", xbusd->xbusd_path, revtchn));
        err = xenbus_read(NULL, xbusd->xbusd_otherend, "protocol",
            &len, &xsproto);
        if (err) {
                xbdi->xbdi_proto = XBDIP_NATIVE;
                proto = "unspecified";
+               XENPRINTF(("xbdback %s: connect no xsproto\n", xbusd->xbusd_path));
        } else {
+               XENPRINTF(("xbdback %s: connect xsproto %s\n", xbusd->xbusd_path, xsproto));
                if (strcmp(xsproto, XEN_IO_PROTO_ABI_NATIVE) == 0) {
                        xbdi->xbdi_proto = XBDIP_NATIVE;
                        proto = XEN_IO_PROTO_ABI_NATIVE;
@@ -566,8 +571,8 @@
                        free(xsproto, M_DEVBUF);
                        return -1;
                }
+               free(xsproto, M_DEVBUF);
        }
-       free(xsproto, M_DEVBUF);
 
        /* allocate VA space and map rings */
        xbdi->xbdi_ring_va = uvm_km_alloc(kernel_map, PAGE_SIZE, 0,
@@ -577,6 +582,7 @@
                    "can't get VA for ring", xbusd->xbusd_otherend);
                return -1;
        }
+       XENPRINTF(("xbdback %s: connect va 0x%" PRIxVADDR "\n", xbusd->xbusd_path, xbdi->xbdi_ring_va));
 
        grop.host_addr = xbdi->xbdi_ring_va;
        grop.flags = GNTMAP_host_map;
@@ -592,6 +598,7 @@
                goto err;
        }
        xbdi->xbdi_ring_handle = grop.handle;
+       XENPRINTF(("xbdback %s: connect grhandle %d\n", xbusd->xbusd_path, grop.handle));
 
        switch(xbdi->xbdi_proto) {
        case XBDIP_NATIVE:
@@ -626,6 +633,7 @@
                    "can't bind event channel", xbusd->xbusd_otherend);
                goto err2;
        }
+       XENPRINTF(("xbdback %s: connect evchannel %d\n", xbusd->xbusd_path, xbdi->xbdi_evtchn));
        xbdi->xbdi_evtchn = evop.u.bind_interdomain.local_port;
 
        event_set_handler(xbdi->xbdi_evtchn, xbdback_evthandler,
@@ -765,6 +773,7 @@
                xbdi->xbdi_ro = false;
        else
                xbdi->xbdi_ro = true;
+       free(mode, M_DEVBUF);
        major = major(xbdi->xbdi_dev);
        devname = devsw_blk2name(major);
        if (devname == NULL) {