While this fixes the race and error on shutdown of a HVM guest with
pci-passthrough,
i don't know if this could give problems in other areas (migration ?),
hence posted as RFC.
--
Sander
8< -----------
At present on shutdown when using pci-passthrough with qemu-xen, qemu closes
the QMP
socket before libxl is done with it causing these errors to be logged by libxl:
Waiting for domain test (domid 1) to die [pid 11568]
Domain 1 has shut down, reason code 0 0x0
Action for shutdown reason code 0 is destroy
Domain 1 needs to be cleaned up: destroying the domain
libxl: error: libxl_qmp.c:443:qmp_next: Socket read error: Connection reset
by peer
libxl: error: libxl_qmp.c:701:libxl__qmp_initialize: Failed to connect to
QMP
libxl: error: libxl_qmp.c:686:libxl__qmp_initialize: Connection error:
Connection refused
libxl: error: libxl_dm.c:1588:kill_device_model: Device Model already exited
Done. Exiting now
Prevent this by using the qemu '-no-shutdown' parameter which is described as
doing:
"Don’t exit QEMU on guest shutdown, but instead only stop the emulation.
This allows for instance switching to monitor to commit changes to the
disk image."
So Qemu will stop emulating, but keeps the QMP socket open and waits for libxl
to
kill the qemu process when it is done, preventing the race and resulting in this
to be logged by libxl:
Waiting for domain test (domid 1) to die [pid 10859]
Domain 1 has shut down, reason code 0 0x0
Action for shutdown reason code 0 is destroy
Domain 1 needs to be cleaned up: destroying the domain
Done. Exiting now
Signed-off-by: Sander Eikelenboom <li...@eikelenboom.it>
---
tools/libxl/libxl_dm.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
index fc3f5a7..3152c87 100644
--- a/tools/libxl/libxl_dm.c
+++ b/tools/libxl/libxl_dm.c
@@ -435,6 +435,7 @@ static char ** libxl__build_device_model_args_new(libxl__gc
*gc,
"path=%s/qmp-libxl-%d,server,nowait",
libxl__run_dir_path(), guest_domid));
+ flexarray_append(dm_args, "-no-shutdown");
flexarray_append(dm_args, "-mon");
flexarray_append(dm_args, "chardev=libxl-cmd,mode=control");
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel
