From 00782050707fbb999bfffe722794490d2211a0a9 Mon Sep 17 00:00:00 2001

From: Dustin Kirkland <kirkland@canonical.com>

Date: Fri, 4 Sep 2009 14:38:30 -0500

Subject: [PATCH] qemu-kvm: fix segfault when running kvm without /dev/kvm

qemu-kvm segfaults on systems without access to /dev/kvm.

The global kvm_allowed is being set too late in vl.c.

This patch moves the kvm initialization a bit higher in the

vl.c main, just after the daemonize fork.

This fix is intended to be a short term solution, solving the

segfaults.

In the longer term, the suggested approach requires a bit more

development and testing:

 * If no arg given          => try kvm, try kqemu, try tcg

 * If --accelmode arg given => try $arg, and fail if unavailable

(cherry picked from commit c06b44bfc9814930b6a94db7bbeb3be1cd39c0d2)

Signed-off-by: Dustin Kirkland <kirkland@canonical.com>

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

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

Fedora-patch: qemu-fix-no-kvm-segfault.patch

---

 vl.c |   28 ++++++++++++++--------------

 1 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/vl.c b/vl.c

index db75470..26bced8 100644

--- a/vl.c

+++ b/vl.c

@@ -5831,6 +5831,20 @@ int main(int argc, char **argv, char **envp)

     }

 #endif

+    if (kvm_enabled()) {

+        int ret;

+

+        ret = kvm_init(smp_cpus);

+        if (ret < 0) {

+#if defined(KVM_UPSTREAM) || defined(NO_CPU_EMULATION)

+            fprintf(stderr, "failed to initialize KVM\n");

+            exit(1);

+#endif

+            fprintf(stderr, "Could not initialize KVM, will disable KVM support\n");

+            kvm_allowed = 0;

+        }

+    }

+

 #ifdef CONFIG_KQEMU

     if (smp_cpus > 1)

         kqemu_allowed = 0;

@@ -6002,20 +6016,6 @@ int main(int argc, char **argv, char **envp)

         }

     }

-    if (kvm_enabled()) {

-        int ret;

-

-        ret = kvm_init(smp_cpus);

-        if (ret < 0) {

-#if defined(KVM_UPSTREAM) || defined(NO_CPU_EMULATION)

-            fprintf(stderr, "failed to initialize KVM\n");

-            exit(1);

-#endif

-            fprintf(stderr, "Could not initialize KVM, will disable KVM support\n");

-	     kvm_allowed = 0;

-        }

-    }

-

     if (monitor_device) {

         monitor_hd = qemu_chr_open("monitor", monitor_device, NULL);

         if (!monitor_hd) {

-- 

1.6.2.5