staging: hv: convert vmbus_on_msg_dpc to not call osd_schedule_callback

The additional abstraction is unneeded. This also fixes a sleeping
while atomic issue as osd_schedule_callback can sleep which is
not allowed for vmbus_on_msg_dpc running in a tasklet.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=16701

Reviewed-By: Hank Janssen <hjanssen@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/hv/channel_mgmt.c b/drivers/staging/hv/channel_mgmt.c
index 0f4d609..6f393e7 100644 (file)
--- a/drivers/staging/hv/channel_mgmt.c
+++ b/drivers/staging/hv/channel_mgmt.c
@@ -753,7 +753,6 @@ void vmbus_onmessage(void *context)
                           hdr->msgtype, size);
                print_hex_dump_bytes("", DUMP_PREFIX_NONE,
                                     (unsigned char *)msg->u.payload, size);
-               kfree(msg);
                return;
        }
 
@@ -762,9 +761,6 @@ void vmbus_onmessage(void *context)
        else
                DPRINT_ERR(VMBUS, "Unhandled channel message type %d",
                           hdr->msgtype);
-
-       /* Free the msg that was allocated in VmbusOnMsgDPC() */
-       kfree(msg);
 }
 
 /*

diff --git a/drivers/staging/hv/vmbus_drv.c b/drivers/staging/hv/vmbus_drv.c
index d794b60..84fdb64 100644 (file)
--- a/drivers/staging/hv/vmbus_drv.c
+++ b/drivers/staging/hv/vmbus_drv.c
@@ -203,6 +203,21 @@ static void VmbusOnCleanup(struct hv_driver *drv)
        hv_cleanup();
 }
 
+struct onmessage_work_context {
+       struct work_struct work;
+       struct hv_message msg;
+};
+
+static void vmbus_onmessage_work(struct work_struct *work)
+{
+       struct onmessage_work_context *ctx;
+
+       ctx = container_of(work, struct onmessage_work_context,
+                          work);
+       vmbus_onmessage(&ctx->msg);
+       kfree(ctx);
+}
+
 /*
  * vmbus_on_msg_dpc - DPC routine to handle messages from the hypervisior
  */
@@ -212,20 +227,19 @@ static void vmbus_on_msg_dpc(struct hv_driver *drv)
        void *page_addr = hv_context.synic_message_page[cpu];
        struct hv_message *msg = (struct hv_message *)page_addr +
                                  VMBUS_MESSAGE_SINT;
-       struct hv_message *copied;
+       struct onmessage_work_context *ctx;
 
        while (1) {
                if (msg->header.message_type == HVMSG_NONE) {
                        /* no msg */
                        break;
                } else {
-                       copied = kmemdup(msg, sizeof(*copied), GFP_ATOMIC);
-                       if (copied == NULL)
+                       ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC);
+                       if (ctx == NULL)
                                continue;
-
-                       osd_schedule_callback(gVmbusConnection.WorkQueue,
-                                             vmbus_onmessage,
-                                             (void *)copied);
+                       INIT_WORK(&ctx->work, vmbus_onmessage_work);
+                       memcpy(&ctx->msg, msg, sizeof(*msg));
+                       queue_work(gVmbusConnection.WorkQueue, &ctx->work);
                }
 
                msg->header.message_type = HVMSG_NONE;