qemu: assign correct type of PCI address for vhost-scsi when using pcie-root
Commit 10c73bf1 fixed a bug that I had introduced back in commit
70249927 - if a vhost-scsi device had no manually assigned PCI
address, one wouldn't be assigned automatically. There was a slight
problem with the logic of the fix though - in the case of domains with
pcie-root (e.g. those with a q35 machinetype),
qemuDomainDeviceCalculatePCIConnectFlags() will attempt to determine
if the host-side PCI device is Express or legacy by examining sysfs
based on the host-side PCI address stored in
hostdev->source.subsys.u.pci.addr, but that part of the union is only
valid for PCI hostdevs, *not* for SCSI hostdevs. So we end up trying
to read sysfs for some probably-non-existent device, which fails, and
the function virPCIDeviceIsPCIExpress() returns failure (-1).
By coincidence, the return value is being examined as a boolean, and
since -1 is true, we still end up assigning the vhost-scsi device to
an Express slot, but that is just by chance (and could fail in the
case that the gibberish in the "hostside PCI address" was the address
of a real device that happened to be legacy PCI).
Since (according to Paolo Bonzini) vhost-scsi devices appear just like
virtio-scsi devices in the guest, they should follow the same rules as
virtio devices when deciding whether they should be placed in an
Express or a legacy slot. That's accomplished in this patch by
returning early with virtioFlags, rather than erroneously using
hostdev->source.subsys.u.pci.addr. It also adds a test case for PCIe
to assure it doesn't get broken in the future.
2017-12-15 19:42:35 +03:00
<domain type= 'kvm' >
<name > QEMUGuest2</name>
<uuid > c7a5fdbd-edaf-9466-926a-d65c16db1809</uuid>
<memory unit= 'KiB' > 219100</memory>
<currentMemory unit= 'KiB' > 219100</currentMemory>
<vcpu placement= 'static' > 1</vcpu>
<os >
2022-01-05 12:19:36 +03:00
<type arch= 'x86_64' machine= 'q35' > hvm</type>
qemu: assign correct type of PCI address for vhost-scsi when using pcie-root
Commit 10c73bf1 fixed a bug that I had introduced back in commit
70249927 - if a vhost-scsi device had no manually assigned PCI
address, one wouldn't be assigned automatically. There was a slight
problem with the logic of the fix though - in the case of domains with
pcie-root (e.g. those with a q35 machinetype),
qemuDomainDeviceCalculatePCIConnectFlags() will attempt to determine
if the host-side PCI device is Express or legacy by examining sysfs
based on the host-side PCI address stored in
hostdev->source.subsys.u.pci.addr, but that part of the union is only
valid for PCI hostdevs, *not* for SCSI hostdevs. So we end up trying
to read sysfs for some probably-non-existent device, which fails, and
the function virPCIDeviceIsPCIExpress() returns failure (-1).
By coincidence, the return value is being examined as a boolean, and
since -1 is true, we still end up assigning the vhost-scsi device to
an Express slot, but that is just by chance (and could fail in the
case that the gibberish in the "hostside PCI address" was the address
of a real device that happened to be legacy PCI).
Since (according to Paolo Bonzini) vhost-scsi devices appear just like
virtio-scsi devices in the guest, they should follow the same rules as
virtio devices when deciding whether they should be placed in an
Express or a legacy slot. That's accomplished in this patch by
returning early with virtioFlags, rather than erroneously using
hostdev->source.subsys.u.pci.addr. It also adds a test case for PCIe
to assure it doesn't get broken in the future.
2017-12-15 19:42:35 +03:00
<boot dev= 'hd' />
</os>
<clock offset= 'utc' />
<on_poweroff > destroy</on_poweroff>
<on_reboot > restart</on_reboot>
<on_crash > destroy</on_crash>
<devices >
<emulator > /usr/bin/qemu-system-x86_64</emulator>
<controller type= 'usb' index= '0' model= 'none' />
<controller type= 'sata' index= '0' >
<address type= 'pci' domain= '0x0000' bus= '0x00' slot= '0x1f' function= '0x2' />
</controller>
<controller type= 'pci' index= '0' model= 'pcie-root' />
<controller type= 'pci' index= '1' model= 'pcie-root-port' >
<model name= 'pcie-root-port' />
2021-03-30 18:48:46 +03:00
<target chassis= '1' port= '0x8' />
<address type= 'pci' domain= '0x0000' bus= '0x00' slot= '0x01' function= '0x0' multifunction= 'on' />
qemu: assign correct type of PCI address for vhost-scsi when using pcie-root
Commit 10c73bf1 fixed a bug that I had introduced back in commit
70249927 - if a vhost-scsi device had no manually assigned PCI
address, one wouldn't be assigned automatically. There was a slight
problem with the logic of the fix though - in the case of domains with
pcie-root (e.g. those with a q35 machinetype),
qemuDomainDeviceCalculatePCIConnectFlags() will attempt to determine
if the host-side PCI device is Express or legacy by examining sysfs
based on the host-side PCI address stored in
hostdev->source.subsys.u.pci.addr, but that part of the union is only
valid for PCI hostdevs, *not* for SCSI hostdevs. So we end up trying
to read sysfs for some probably-non-existent device, which fails, and
the function virPCIDeviceIsPCIExpress() returns failure (-1).
By coincidence, the return value is being examined as a boolean, and
since -1 is true, we still end up assigning the vhost-scsi device to
an Express slot, but that is just by chance (and could fail in the
case that the gibberish in the "hostside PCI address" was the address
of a real device that happened to be legacy PCI).
Since (according to Paolo Bonzini) vhost-scsi devices appear just like
virtio-scsi devices in the guest, they should follow the same rules as
virtio devices when deciding whether they should be placed in an
Express or a legacy slot. That's accomplished in this patch by
returning early with virtioFlags, rather than erroneously using
hostdev->source.subsys.u.pci.addr. It also adds a test case for PCIe
to assure it doesn't get broken in the future.
2017-12-15 19:42:35 +03:00
</controller>
<controller type= 'pci' index= '2' model= 'pcie-root-port' >
<model name= 'pcie-root-port' />
2021-03-30 18:48:46 +03:00
<target chassis= '2' port= '0x9' />
<address type= 'pci' domain= '0x0000' bus= '0x00' slot= '0x01' function= '0x1' />
qemu: assign correct type of PCI address for vhost-scsi when using pcie-root
Commit 10c73bf1 fixed a bug that I had introduced back in commit
70249927 - if a vhost-scsi device had no manually assigned PCI
address, one wouldn't be assigned automatically. There was a slight
problem with the logic of the fix though - in the case of domains with
pcie-root (e.g. those with a q35 machinetype),
qemuDomainDeviceCalculatePCIConnectFlags() will attempt to determine
if the host-side PCI device is Express or legacy by examining sysfs
based on the host-side PCI address stored in
hostdev->source.subsys.u.pci.addr, but that part of the union is only
valid for PCI hostdevs, *not* for SCSI hostdevs. So we end up trying
to read sysfs for some probably-non-existent device, which fails, and
the function virPCIDeviceIsPCIExpress() returns failure (-1).
By coincidence, the return value is being examined as a boolean, and
since -1 is true, we still end up assigning the vhost-scsi device to
an Express slot, but that is just by chance (and could fail in the
case that the gibberish in the "hostside PCI address" was the address
of a real device that happened to be legacy PCI).
Since (according to Paolo Bonzini) vhost-scsi devices appear just like
virtio-scsi devices in the guest, they should follow the same rules as
virtio devices when deciding whether they should be placed in an
Express or a legacy slot. That's accomplished in this patch by
returning early with virtioFlags, rather than erroneously using
hostdev->source.subsys.u.pci.addr. It also adds a test case for PCIe
to assure it doesn't get broken in the future.
2017-12-15 19:42:35 +03:00
</controller>
<input type= 'mouse' bus= 'ps2' />
<input type= 'keyboard' bus= 'ps2' />
2021-02-24 17:24:10 +03:00
<audio id= '1' type= 'none' />
qemu: assign correct type of PCI address for vhost-scsi when using pcie-root
Commit 10c73bf1 fixed a bug that I had introduced back in commit
70249927 - if a vhost-scsi device had no manually assigned PCI
address, one wouldn't be assigned automatically. There was a slight
problem with the logic of the fix though - in the case of domains with
pcie-root (e.g. those with a q35 machinetype),
qemuDomainDeviceCalculatePCIConnectFlags() will attempt to determine
if the host-side PCI device is Express or legacy by examining sysfs
based on the host-side PCI address stored in
hostdev->source.subsys.u.pci.addr, but that part of the union is only
valid for PCI hostdevs, *not* for SCSI hostdevs. So we end up trying
to read sysfs for some probably-non-existent device, which fails, and
the function virPCIDeviceIsPCIExpress() returns failure (-1).
By coincidence, the return value is being examined as a boolean, and
since -1 is true, we still end up assigning the vhost-scsi device to
an Express slot, but that is just by chance (and could fail in the
case that the gibberish in the "hostside PCI address" was the address
of a real device that happened to be legacy PCI).
Since (according to Paolo Bonzini) vhost-scsi devices appear just like
virtio-scsi devices in the guest, they should follow the same rules as
virtio devices when deciding whether they should be placed in an
Express or a legacy slot. That's accomplished in this patch by
returning early with virtioFlags, rather than erroneously using
hostdev->source.subsys.u.pci.addr. It also adds a test case for PCIe
to assure it doesn't get broken in the future.
2017-12-15 19:42:35 +03:00
<hostdev mode= 'subsystem' type= 'scsi_host' managed= 'no' >
<source protocol= 'vhost' wwpn= 'naa.5123456789abcde0' />
<address type= 'pci' domain= '0x0000' bus= '0x01' slot= '0x00' function= '0x0' />
</hostdev>
<memballoon model= 'none' />
</devices>
</domain>
