patch-0002-libxl-attach-PCI-device-to-qemu-only-after-setting-p.patch

From be920c5c4906aa41a8d0d035a23dd9b5122f12b1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Marczykowski-G=C3=B3recki?=
 <marmarek@invisiblethingslab.com>
Date: Mon, 17 Oct 2016 23:03:28 +0200
Subject: [PATCH 2/3] libxl: attach PCI device to qemu only after setting
 pciback/pcifront
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Organization: Invisible Things Lab
Cc: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>

When qemu is running in stubdomain, handling "pci-ins" command will fail
if pcifront is not initialized already. Fix this by sending such command
only after confirming that pciback/front is running.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
---
 tools/libxl/libxl_pci.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/tools/libxl/libxl_pci.c b/tools/libxl/libxl_pci.c
index 2942772..d3cf843 100644
--- a/tools/libxl/libxl_pci.c
+++ b/tools/libxl/libxl_pci.c
@@ -1084,6 +1084,7 @@ int libxl__device_pci_add(libxl__gc *gc, uint32_t domid, libxl_device_pci *pcide
 {
     libxl_ctx *ctx = libxl__gc_owner(gc);
     unsigned int orig_vdev, pfunc_mask;
+    char *be_path;
     libxl_device_pci *assigned;
     int num_assigned, i, rc;
     int stubdomid = 0;
@@ -1137,6 +1138,14 @@ int libxl__device_pci_add(libxl__gc *gc, uint32_t domid, libxl_device_pci *pcide
         rc = do_pci_add(gc, stubdomid, &pcidev_s, 0);
         if ( rc )
             goto out;
+        /* wait for the device actually being connected, otherwise device model
+         * running there will fail to find the device */
+        be_path = libxl__sprintf(gc, "%s/backend/pci/%d/0",
+                libxl__xs_get_dompath(gc, 0), stubdomid);
+        rc = libxl__wait_for_backend(gc, be_path,
+                    GCSPRINTF("%d", XenbusStateConnected));
+        if ( rc )
+            goto out;
     }
 
     orig_vdev = pcidev->vdevfn & ~7U;
-- 
2.5.5