[Qemu-devel] [PATCH v4 04/33] vl.c: daemonize before guest memory allocation

[Igor Mammedov]

memory allocated for guest before QEMU is daemonized and then mapped
later in guest's address space after it is daemonized, leads to EPT
violation and QEMU aborts.

To avoid this and similar issues switch to daemonized mode early
before applying/processing other options.

Signed-off-by: Igor Mammedov <address@hidden>
Acked-by: Peter Crosthwaite <address@hidden>
---
I haven't digged in kvm itself yet why EPT violation happens,
but fix on QEMU side looks trivial so it won't hurt to use it anyway.

there is simpler reporoducer without migration, start guest with
 '-object memory-ram,id=foo,size=1G'
when guest is up and running hotplug dimm device using 'foo' memdev
as backend.
---
 vl.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/vl.c b/vl.c
index 037aa62..2449d78 100644
--- a/vl.c
+++ b/vl.c
@@ -3965,6 +3965,8 @@ int main(int argc, char **argv, char **envp)
     }
     loc_set_none();
 
+    os_daemonize();
+
     if (qemu_init_main_loop()) {
         fprintf(stderr, "qemu_init_main_loop failed\n");
         exit(1);
@@ -4206,8 +4208,6 @@ int main(int argc, char **argv, char **envp)
     }
 #endif
 
-    os_daemonize();
-
     if (pid_file && qemu_create_pidfile(pid_file) != 0) {
         os_pidfile_error();
         exit(1);
-- 
1.7.1