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 be 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 at least) 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.
---
src/qemu/qemu_domain_address.c | 7 ++++
.../hostdev-scsi-vhost-scsi-pcie.args | 25 ++++++++++++++
.../hostdev-scsi-vhost-scsi-pcie.xml | 23 +++++++++++++
tests/qemuxml2argvtest.c | 7 ++++
.../hostdev-scsi-vhost-scsi-pcie.xml | 40 ++++++++++++++++++++++
tests/qemuxml2xmltest.c | 7 ++++
6 files changed, 109 insertions(+)
create mode 100644 tests/qemuxml2argvdata/hostdev-scsi-vhost-scsi-pcie.args
create mode 100644 tests/qemuxml2argvdata/hostdev-scsi-vhost-scsi-pcie.xml
create mode 100644 tests/qemuxml2xmloutdata/hostdev-scsi-vhost-scsi-pcie.xml
diff --git a/src/qemu/qemu_domain_address.c b/src/qemu/qemu_domain_address.c
index 6e7561d39..600de85f8 100644
--- a/src/qemu/qemu_domain_address.c
+++ b/src/qemu/qemu_domain_address.c
@@ -656,6 +656,13 @@ qemuDomainDeviceCalculatePCIConnectFlags(virDomainDeviceDefPtr dev,
if (hostdev->source.subsys.type == VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_MDEV)
return pcieFlags;
+ /* according to pbonzini, from the guest PoV vhost-scsi devices
+ * are the same as virtio-scsi, so they should use virtioFlags
+ * (same as virtio-scsi) to determine Express vs. legacy placement
+ */
+ if (hostdev->source.subsys.type == VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_SCSI_HOST)
+ return virtioFlags;
+
if (!(pciDev = virPCIDeviceNew(hostAddr->domain,
hostAddr->bus,
hostAddr->slot,
diff --git a/tests/qemuxml2argvdata/hostdev-scsi-vhost-scsi-pcie.args b/tests/qemuxml2argvdata/hostdev-scsi-vhost-scsi-pcie.args
new file mode 100644
index 000000000..296716f58
--- /dev/null
+++ b/tests/qemuxml2argvdata/hostdev-scsi-vhost-scsi-pcie.args
@@ -0,0 +1,25 @@
+LC_ALL=C \
+PATH=/bin \
+HOME=/home/test \
+USER=test \
+LOGNAME=test \
+QEMU_AUDIO_DRV=none \
+/usr/bin/qemu-system-x86_64 \
+-name QEMUGuest2 \
+-S \
+-M pc-q35-2.7 \
+-m 214 \
+-smp 1,sockets=1,cores=1,threads=1 \
+-uuid c7a5fdbd-edaf-9466-926a-d65c16db1809 \
+-nographic \
+-nodefaults \
+-chardev socket,id=charmonitor,path=/tmp/lib/domain--1-QEMUGuest2/monitor.sock,\
+server,nowait \
+-mon chardev=charmonitor,id=monitor,mode=readline \
+-no-acpi \
+-boot c \
+-device pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,\
+multifunction=on,addr=0x2 \
+-device pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1 \
+-device vhost-scsi-pci,wwpn=naa.5123456789abcde0,vhostfd=3,id=hostdev0,\
+bus=pci.1,addr=0x0
diff --git a/tests/qemuxml2argvdata/hostdev-scsi-vhost-scsi-pcie.xml b/tests/qemuxml2argvdata/hostdev-scsi-vhost-scsi-pcie.xml
new file mode 100644
index 000000000..c4e8c33a9
--- /dev/null
+++ b/tests/qemuxml2argvdata/hostdev-scsi-vhost-scsi-pcie.xml
@@ -0,0 +1,23 @@
+<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>
+ <type arch='x86_64' machine='pc-q35-2.7'>hvm</type>
+ <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'/>
+ <hostdev mode='subsystem' type='scsi_host' managed='no'>
+ <source protocol='vhost' wwpn='naa.5123456789abcde0'/>
+ </hostdev>
+ <memballoon model='none'/>
+ </devices>
+</domain>
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index ca24e0bbb..d5b2881e7 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -2465,6 +2465,13 @@ mymain(void)
DO_TEST("hostdev-scsi-vhost-scsi-pci",
QEMU_CAPS_VIRTIO_SCSI, QEMU_CAPS_DEVICE_VHOST_SCSI,
QEMU_CAPS_DEVICE_SCSI_GENERIC);
+ DO_TEST("hostdev-scsi-vhost-scsi-pcie",
+ QEMU_CAPS_KVM,
+ QEMU_CAPS_VIRTIO_SCSI, QEMU_CAPS_DEVICE_VHOST_SCSI,
+ QEMU_CAPS_DEVICE_SCSI_GENERIC,
+ QEMU_CAPS_PCI_MULTIFUNCTION,
+ QEMU_CAPS_DEVICE_PCIE_ROOT_PORT,
+ QEMU_CAPS_VIRTIO_PCI_DISABLE_LEGACY);
DO_TEST("mlock-on", QEMU_CAPS_REALTIME_MLOCK);
DO_TEST_FAILURE("mlock-on", NONE);
diff --git a/tests/qemuxml2xmloutdata/hostdev-scsi-vhost-scsi-pcie.xml b/tests/qemuxml2xmloutdata/hostdev-scsi-vhost-scsi-pcie.xml
new file mode 100644
index 000000000..ef48d8123
--- /dev/null
+++ b/tests/qemuxml2xmloutdata/hostdev-scsi-vhost-scsi-pcie.xml
@@ -0,0 +1,40 @@
+<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>
+ <type arch='x86_64' machine='pc-q35-2.7'>hvm</type>
+ <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'/>
+ <target chassis='1' port='0x10'/>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0' multifunction='on'/>
+ </controller>
+ <controller type='pci' index='2' model='pcie-root-port'>
+ <model name='pcie-root-port'/>
+ <target chassis='2' port='0x11'/>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x1'/>
+ </controller>
+ <input type='mouse' bus='ps2'/>
+ <input type='keyboard' bus='ps2'/>
+ <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>
diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c
index 2be8eb2c1..78519f509 100644
--- a/tests/qemuxml2xmltest.c
+++ b/tests/qemuxml2xmltest.c
@@ -1109,6 +1109,13 @@ mymain(void)
DO_TEST("hostdev-scsi-vhost-scsi-pci",
QEMU_CAPS_VIRTIO_SCSI, QEMU_CAPS_DEVICE_VHOST_SCSI,
QEMU_CAPS_DEVICE_SCSI_GENERIC);
+ DO_TEST("hostdev-scsi-vhost-scsi-pcie",
+ QEMU_CAPS_KVM,
+ QEMU_CAPS_VIRTIO_SCSI, QEMU_CAPS_DEVICE_VHOST_SCSI,
+ QEMU_CAPS_DEVICE_SCSI_GENERIC,
+ QEMU_CAPS_PCI_MULTIFUNCTION,
+ QEMU_CAPS_DEVICE_PCIE_ROOT_PORT,
+ QEMU_CAPS_VIRTIO_PCI_DISABLE_LEGACY);
DO_TEST("hostdev-scsi-lsi",
QEMU_CAPS_VIRTIO_SCSI, QEMU_CAPS_SCSI_LSI,
QEMU_CAPS_DEVICE_SCSI_GENERIC);
--
2.13.6
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On 12/18/2017 10:35 AM, Laine Stump wrote: > 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 be 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). ^^ Probably something that should be fixed as a separate patch? Hazards of the undocumented virPCIDeviceIsPCIExpress return values. > > Since (according to Paolo Bonzini at least) 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. > --- > src/qemu/qemu_domain_address.c | 7 ++++ > .../hostdev-scsi-vhost-scsi-pcie.args | 25 ++++++++++++++ > .../hostdev-scsi-vhost-scsi-pcie.xml | 23 +++++++++++++ > tests/qemuxml2argvtest.c | 7 ++++ > .../hostdev-scsi-vhost-scsi-pcie.xml | 40 ++++++++++++++++++++++ > tests/qemuxml2xmltest.c | 7 ++++ > 6 files changed, 109 insertions(+) > create mode 100644 tests/qemuxml2argvdata/hostdev-scsi-vhost-scsi-pcie.args > create mode 100644 tests/qemuxml2argvdata/hostdev-scsi-vhost-scsi-pcie.xml > create mode 100644 tests/qemuxml2xmloutdata/hostdev-scsi-vhost-scsi-pcie.xml > Reviewed-by: John Ferlan <jferlan@redhat.com> John Thanks - I was wondering about PCIE, but figured/assumed that since it's an HBA sitting on a bus as opposed to a LUN that we're making it look like a disk on the guest, that the code would magically work. Just seemed different enough from a MDEV which is to me more like how a vHBA LUN would be handled as a "child" (so to speak) of some device that's sitting on a bus. -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
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