diff options
| author | Gerd Hoffmann <kraxel@redhat.com> | 2018-05-03 08:29:32 +0200 |
|---|---|---|
| committer | Gerd Hoffmann <kraxel@redhat.com> | 2018-05-07 11:10:42 +0200 |
| commit | 3280ea8edede3814553aa19fa27a58daedd48ad9 (patch) | |
| tree | 502e8c846609cca3c0af952cdb594185fe04a39d | |
| parent | 2392ae6bbb0a940a4fd6df29e704b09cadc14790 (diff) | |
| download | qemu-3280ea8edede3814553aa19fa27a58daedd48ad9.tar.gz | |
usb-host: skip open on pending postload bh
usb-host emulates a device unplug after live migration, because the
device state is unknown and unplug/replug makes sure the guest
re-initializes the device into a working state. This can't be done in
post-load though, so post-load just schedules a bottom half which
executes after vmload is complete.
It can happen that the device autoscan timer hits the race window
between scheduling and running the bottom half, which in turn can
triggers an assert().
Fix that issue by just ignoring the usb_host_open() call in case the
bottom half didn't execute yet.
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1572851
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20180503062932.17233-1-kraxel@redhat.com
| -rw-r--r-- | hw/usb/host-libusb.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/hw/usb/host-libusb.c b/hw/usb/host-libusb.c index dc0a8fe295..f31e9cbbb8 100644 --- a/hw/usb/host-libusb.c +++ b/hw/usb/host-libusb.c @@ -102,6 +102,7 @@ struct USBHostDevice { /* callbacks & friends */ QEMUBH *bh_nodev; QEMUBH *bh_postld; + bool bh_postld_pending; Notifier exit; /* request queues */ @@ -870,6 +871,10 @@ static int usb_host_open(USBHostDevice *s, libusb_device *dev) int rc; Error *local_err = NULL; + if (s->bh_postld_pending) { + return -1; + } + trace_usb_host_open_started(bus_num, addr); if (s->dh != NULL) { @@ -1528,6 +1533,7 @@ static void usb_host_post_load_bh(void *opaque) if (udev->attached) { usb_device_detach(udev); } + dev->bh_postld_pending = false; usb_host_auto_check(NULL); } @@ -1539,6 +1545,7 @@ static int usb_host_post_load(void *opaque, int version_id) dev->bh_postld = qemu_bh_new(usb_host_post_load_bh, dev); } qemu_bh_schedule(dev->bh_postld); + dev->bh_postld_pending = true; return 0; } |