Normally pci_init_bus_master() would be called either via
bus->machine_done.notify or directly from do_pci_register_device().
However if a device's realize() failed, pci_init_bus_master() is not
called, and do_pci_unregister_device() fails on
memory_region_del_subregion() as it was not mapped.
This adds a check that subregion was mapped before unmapping it.
Fixes: c53598ed18e4 ("pci: Add missing drop of bus master AS reference")
Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
---
This is to pass iotest 051 which does run QEMU like this:
ppc64-softmmu/qemu-system-ppc64 -nodefaults -machine accel=qtest -nographic
-monitor stdio -serial none -drive if=virtio
which normally fails with:
qemu-system-ppc64: -drive if=virtio: Device needs media, but drive is empty
or asserts (without this patch):
qemu-system-ppc64: /home/aik/p/qemu-kvm/memory.c:2118:
memory_region_del_subregion: Assertion `subregion->container == mr' failed.
---
hw/pci/pci.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index bd8043c460..259483b1c0 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -869,8 +869,10 @@ static void do_pci_unregister_device(PCIDevice *pci_dev)
pci_dev->bus->devices[pci_dev->devfn] = NULL;
pci_config_free(pci_dev);
- memory_region_del_subregion(&pci_dev->bus_master_container_region,
- &pci_dev->bus_master_enable_region);
+ if (memory_region_is_mapped(&pci_dev->bus_master_enable_region)) {
+ memory_region_del_subregion(&pci_dev->bus_master_container_region,
+ &pci_dev->bus_master_enable_region);
+ }
address_space_destroy(&pci_dev->bus_master_as);
}
--
2.11.0
