Hi,
When using virtio disk plug/unplug with q35 machine I see two problems. Note
that when using the same sequence with default 440FX I see no issues.
A) 'pcie.0' does not support hotplugging'
I can workaround this problem if I manually specify
"-readconfig /usr/share/qemu/Q35-chipset.cfg" on the QEMU command line and
use the following monitor command to plug the disk:
(qemu) device_add
virtio-blk-pci,id=device1,drive=drive1,scsi=on,bus=ich9-pcie-port-1
The content of Q35-chipset.cfg is:
[device "ich9-pcie-port-1"]
driver = "ioh3420"
multifunction = "on"
bus = "pcie.0"
B) Upon disk unplug QEMU is crashing. This is with recent qemu.git. The
following patch
solve the issue.
Signed-off-by: Etienne Martineau <etmarti...@gmail.com>
---
hw/pci/pcie.c | 16 +++++++++++++++-
1 files changed, 15 insertions(+), 1 deletions(-)
diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
index 02cde6f..4cf8f4c 100644
--- a/hw/pci/pcie.c
+++ b/hw/pci/pcie.c
@@ -261,17 +261,31 @@ void pcie_cap_slot_hotplug_cb(HotplugHandler
*hotplug_dev, DeviceState *dev,
pcie_cap_slot_event(PCI_DEVICE(hotplug_dev), PCI_EXP_HP_EV_PDC);
}
+/* Upon hot unplugged the device object must be stay until guest OS finish
+ * device removal ( at least for virtio-pci ). On non PCI Express there is no
+ * issue because the clean up is part of acpi_pcihp_eject_slot().
+ */
+static void pcie_cap_slot_hot_unplug_cleanup(void *opaque)
+{
+ DeviceState *dev = opaque;
+ object_unparent(OBJECT(dev));
+}
+
void pcie_cap_slot_hot_unplug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
Error **errp)
{
uint8_t *exp_cap;
+ QEMUTimer *timer;
pcie_cap_slot_hotplug_common(PCI_DEVICE(hotplug_dev), dev, &exp_cap, errp);
- object_unparent(OBJECT(dev));
pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA,
PCI_EXP_SLTSTA_PDS);
pcie_cap_slot_event(PCI_DEVICE(hotplug_dev), PCI_EXP_HP_EV_PDC);
+
+ timer = timer_new_ms(QEMU_CLOCK_REALTIME,
+ pcie_cap_slot_hot_unplug_cleanup, dev);
+ timer_mod(timer, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 1000 );
}
/* pci express slot for pci express root/downstream port
--
1.7.0.4
