When a controller is created with a MSI-X exclusive BAR, the bar0 memory region
is not used at all, and so, the iomem region is not added as a subregion of it.
However, when removing a NVMe controller, the iomem region is unconditionally
removed as a subregion of bar0, causing an assertion failure. Remove the iomem
memory region as a subregion of bar0 only if not using a MSI-X exclusive BAR.
QEMU options (requires a hotunplug-aware OS):
-M q35 -device pcie-root-port,id=rp0 \
-device nvme,serial=ctrl0,id=ctrl0,bus=rp0,msix-exclusive-bar=on
In the QEMU monitor, or by causing an ejection from the OS:
device_del ctrl0
Message in stderr:
qemu-system-x86_64: ../system/memory.c:2617: memory_region_del_subregion:
Assertion `subregion->container == mr' failed.
Fixes: fa905f65c554 ("hw/nvme: add machine compatibility parameter to enable
msix exclusive bar")
Fixes: 9162f1012576 ("hw/nvme: fix msix_uninit with exclusive bar")
Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/4090
Signed-off-by: Daniel Paziyski <[email protected]>
---
hw/nvme/ctrl.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c
index a67e159889..142fbe033e 100644
--- a/hw/nvme/ctrl.c
+++ b/hw/nvme/ctrl.c
@@ -9710,10 +9710,9 @@ static void nvme_exit(PCIDevice *pci_dev)
msix_uninit_exclusive_bar(pci_dev);
} else {
msix_uninit(pci_dev, &n->bar0, &n->bar0);
+ memory_region_del_subregion(&n->bar0, &n->iomem);
}
- memory_region_del_subregion(&n->bar0, &n->iomem);
-
migrate_del_blocker(&n->migration_blocker);
}
--
2.55.0
