During coredump analysis, it is not easy to obtain the address of
backend_info in xen-netback.
So far there are two ways to obtain backend_info:
1. Do what xenbus_device_find() does for vmcore to find the xenbus_device
and then derive it from dev_get_drvdata().
2. Extract backend_info from callstack of xenwatch (e.g., netback_remove()
or frontend_changed()).
This patch adds a reference from xenvif to backend_info so that it would be
much more easier to obtain backend_info during coredump analysis.
Signed-off-by: Dongli Zhang <[email protected]>
---
drivers/net/xen-netback/common.h | 18 ++++++++++++++++++
drivers/net/xen-netback/xenbus.c | 17 +----------------
2 files changed, 19 insertions(+), 16 deletions(-)
diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h
index 936c0b3..05847eb 100644
--- a/drivers/net/xen-netback/common.h
+++ b/drivers/net/xen-netback/common.h
@@ -248,6 +248,22 @@ struct xenvif_hash {
struct xenvif_hash_cache cache;
};
+struct backend_info {
+ struct xenbus_device *dev;
+ struct xenvif *vif;
+
+ /* This is the state that will be reflected in xenstore when any
+ * active hotplug script completes.
+ */
+ enum xenbus_state state;
+
+ enum xenbus_state frontend_state;
+ struct xenbus_watch hotplug_status_watch;
+ u8 have_hotplug_status_watch:1;
+
+ const char *hotplug_script;
+};
+
struct xenvif {
/* Unique identifier for this interface. */
domid_t domid;
@@ -283,6 +299,8 @@ struct xenvif {
struct xenbus_watch credit_watch;
struct xenbus_watch mcast_ctrl_watch;
+ struct backend_info *be;
+
spinlock_t lock;
#ifdef CONFIG_DEBUG_FS
diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index 330ddb6..41c9e8f 100644
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c
@@ -22,22 +22,6 @@
#include <linux/vmalloc.h>
#include <linux/rtnetlink.h>
-struct backend_info {
- struct xenbus_device *dev;
- struct xenvif *vif;
-
- /* This is the state that will be reflected in xenstore when any
- * active hotplug script completes.
- */
- enum xenbus_state state;
-
- enum xenbus_state frontend_state;
- struct xenbus_watch hotplug_status_watch;
- u8 have_hotplug_status_watch:1;
-
- const char *hotplug_script;
-};
-
static int connect_data_rings(struct backend_info *be,
struct xenvif_queue *queue);
static void connect(struct backend_info *be);
@@ -472,6 +456,7 @@ static int backend_create_xenvif(struct backend_info *be)
return err;
}
be->vif = vif;
+ vif->be = be;
kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE);
return 0;
--
2.7.4
On Fri, Apr 12, 2019 at 02:53:24PM +0800, Dongli Zhang wrote:
> During coredump analysis, it is not easy to obtain the address of
> backend_info in xen-netback.
>
> So far there are two ways to obtain backend_info:
>
> 1. Do what xenbus_device_find() does for vmcore to find the xenbus_device
> and then derive it from dev_get_drvdata().
>
> 2. Extract backend_info from callstack of xenwatch (e.g., netback_remove()
> or frontend_changed()).
>
> This patch adds a reference from xenvif to backend_info so that it would be
> much more easier to obtain backend_info during coredump analysis.
>
> Signed-off-by: Dongli Zhang <[email protected]>
Acked-by: Wei Liu <[email protected]>
From: Dongli Zhang <[email protected]>
Date: Fri, 12 Apr 2019 14:53:24 +0800
> During coredump analysis, it is not easy to obtain the address of
> backend_info in xen-netback.
>
> So far there are two ways to obtain backend_info:
>
> 1. Do what xenbus_device_find() does for vmcore to find the xenbus_device
> and then derive it from dev_get_drvdata().
>
> 2. Extract backend_info from callstack of xenwatch (e.g., netback_remove()
> or frontend_changed()).
>
> This patch adds a reference from xenvif to backend_info so that it would be
> much more easier to obtain backend_info during coredump analysis.
>
> Signed-off-by: Dongli Zhang <[email protected]>
Applied to net-next.