From 0b341eda83cd2f01134d5b13300d97c07a3abced Mon Sep 17 00:00:00 2001

From: Michael S. Tsirkin <mst@redhat.com>

Date: Thu, 23 Jul 2009 16:34:13 +0300

Subject: [PATCH] Fix error handling in msix vector add

When adding a vector fails, the used counter should

not be incremented, otherwise on vector change we will

try to update the routing entry.

(cherry picked from commit aca6915d92743b11ac5555d6e412cc4737f27f34)

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Signed-off-by: Avi Kivity <avi@redhat.com>

Signed-off-by: Mark McLoughlin <markmc@redhat.com>

Fedora-patch: qemu-fix-msix-error-handling-on-older-kernels.patch

---

 hw/msix.c |   10 ++++++++--

 1 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/hw/msix.c b/hw/msix.c

index 974268d..b6c3f17 100644

--- a/hw/msix.c

+++ b/hw/msix.c

@@ -503,13 +503,19 @@ void msix_reset(PCIDevice *dev)

 /* Mark vector as used. */

 int msix_vector_use(PCIDevice *dev, unsigned vector)

 {

+    int ret;

     if (vector >= dev->msix_entries_nr)

         return -EINVAL;

-    if (dev->msix_entry_used[vector]++)

+    if (dev->msix_entry_used[vector]) {

         return 0;

+    }

     if (kvm_enabled() && qemu_kvm_irqchip_in_kernel()) {

-        return kvm_msix_add(dev, vector);

+        ret = kvm_msix_add(dev, vector);

+        if (ret) {

+            return ret;

+        }

     }

+    ++dev->msix_entry_used[vector];

     return 0;

 }

-- 

1.6.2.5