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[Qemu-devel] [PATCH 0/1] vfio-pci: fix assert fail in host property if u
[Qemu-devel] [PATCH 0/1] vfio-pci: fix assert fail in host property if unused
Wed, 9 Nov 2016 18:36:19 +0000
Commit 4a946268 changed the default value of the structure
(PCIHostDeviceAddress) underlying the host property in vfio-pci to be ~0 in all
fields. Since this structure has excess bits for representing a standard BDF
(FFFF:FF:FF.F) this triggers an assert check designed to catch such invalid
BDFs in the get function of the property. This makes any code that attempts to
use get on the property fatal if the host device isn't specified using the now
optional host property.
To see the bug assign a vfio-pci device using the sysfsdev property instead of
the host property so that host gets the default "not present," value. Attempts
to display the property then crash the working emulation.
vfio-pci,id=gfxfn0,sysfsdev='/sys/bus/pci/devices/0000:01:00.0' -monitor stdio
QEMU 2.7.50 monitor - type 'help' for more information
(qemu) info qtree
....Omitted for brevity...
dev: vfio-pci, id "gfxfn0"
get_pci_host_devaddr: Assertion `rc == sizeof(buffer) - 1' failed.
The bug is minor because the structure involved is presumably insufficient and
redundant given the introduction of the new sysfsdev property. Since I'm new to
the code, I resisted the urge to make a mess by cleaning it up and attach a
totally minimal fix in the hope it makes the problem clearer and easier to
ignore. Happy to redo or leave it to somebody else as required.
Daniel Oram (1):
Fix assert when get default PCI address property used by vfio-pci
hw/core/qdev-properties.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)
- [Qemu-devel] [PATCH 0/1] vfio-pci: fix assert fail in host property if unused,
Daniel Oram <=