3:24 a.m.
$ cat arm.xml
<domain type="qemu">
<name>f22-arm32</name>
<uuid>a6bc14fb-585b-40b0-a15b-5e19f26079ba</uuid>
<memory>1048576</memory>
<currentMemory>1048576</currentMemory>
<vcpu>1</vcpu>
<os>
<type arch="armv7l" machine="virt">hvm</type>
<boot dev="hd"/>
</os>
<clock offset="utc"/>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>restart</on_crash>
<devices>
<emulator>/usr/bin/qemu-system-arm</emulator>
<disk type="file" device="disk">
<driver name="qemu" type="qcow2"/>
<source file="/home/berrange/VirtualMachines/demo.qcow2"/>
<target dev="sda" bus="scsi"/>
</disk>
<controller type="scsi" index="0"
model="virtio-scsi"/>
<interface type="user">
<mac address="52:54:00:87:d4:c0"/>
<model type="virtio"/>
</interface>
<console type="pty"/>
</devices>
</domain>
$ virsh define arm.xml
Domain f22-arm32 defined from arm.xml
$ virsh start f22-arm32
error: Failed to start domain f22-arm32
error: internal error: qemu unexpectedly closed the monitor: 2017-02-15T09:24:03.967648Z
qemu-system-arm: -device
ioh3420,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x1: MSI is not
supported by interrupt controller
2017-02-15T09:24:03.968154Z qemu-system-arm: -device
ioh3420,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x1: Device
initialization failed
I've not bisected it other than to find it works in 2.5.0 and is
broken in 3.0.0
Regards,
Daniel
--
|: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org -o- http://virt-manager.org :|
|: http://entangle-photo.org -o- http://search.cpan.org/~danberr/ :|
9:58 a.m.
On Wed, 2017-02-15 at 09:24 +0000, Daniel P. Berrange wrote:
[...]
$ virsh start f22-arm32
error: Failed to start domain f22-arm32
error: internal error: qemu unexpectedly closed the monitor: 2017-02-15T09:24:03.967648Z
qemu-system-arm: -device
ioh3420,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x1: MSI is not
supported by interrupt controller
2017-02-15T09:24:03.968154Z qemu-system-arm: -device
ioh3420,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x1: Device
initialization failed
I've not bisected it other than to find it works in 2.5.0 and is
broken in 3.0.0
I'd like you to share a few additional details:
* What does the guest XML look like after libvirt has
had a change to augment it?
* What QEMU command line does libvirt generate based
on said guest XML?
* What QEMU version are you running?
I'm asking because I've just spent some time trying to run
ARM guests[1] on my laptop[2] and I can't reproduce the
failure you're describing, so I need more information to
try and narrow it down.
After the skip, a bunch of unstructured rambling about
stuff I've discovered in the process, interleaved with
more questions about your issue. Have fun! :)
---
I would expect such an error to pop up simply by running
$ qemu-system-arm -nodefaults -M virt \
-device ioh3420,port=0x8,...
Does that happen on your system?
---
I didn't realize the mach-virt machine type was not an
aarch64-only thing. Indeed, it's available through
qemu-system-arm too, and the hardware seems to be the
same, eg. running
$ echo -e 'info qtree\nquit\n' | \
qemu-system-$arch -M virt -monitor stdio
yields the same output.
The only difference AFAICT is that qemu-system-arm limits
the selection of CPUs to 32-bit models only, eg. cortex-a15
is available on both but only qemu-system-aarch64 lets you
use cortex-a57.
---
I know 32-bit UEFI is a thing, because it's used on a bunch
of budget x86 tablet and causes grief and pain to anyone
trying to run Linux on them. However, Fedora only ships
64-bit binaries (edk2-ovmf and edk2-aarch64 packages) so I
can't really try whether an armv7l guest can boot using UEFI.
---
Speaking of booting the guest, how would that work with the
guest XML you're feeding libvirt, exactly? Since you don't
have any sort of firmware, the only way I can see it working
is to to have <kernel>, <initrd> and <cmdline> elements
inside <domain><os>, and libvirt can't possibly figure out
their values for you...
---
Does it help at all to use
<address type='virtio-mmio'/>
in order to force the the SCSI controller and network
interface to use virtio-mmio instead of virtio-pci?
---
As a reference, here's the XML for my Fedora 25/armv7l
guest:
<domain type='qemu'>
<name>f25-armv7l</name>
<uuid>029956e6-5e98-4ca6-8b2b-72322f73f3ea</uuid>
<memory unit='KiB'>2097152</memory>
<currentMemory unit='KiB'>2097152</currentMemory>
<vcpu placement='static'>1</vcpu>
<os>
<type arch='armv7l' machine='virt-2.9'>hvm</type>
<kernel>/home/abologna/.local/share/libvirt/images/f25-armv7l.vmlinuz</kernel>
<initrd>/home/abologna/.local/share/libvirt/images/f25-armv7l.initramfs</initrd>
<cmdline>console=ttyAMA0 rw root=LABEL=_/ rootwait</cmdline>
<boot dev='hd'/>
</os>
<features>
<gic version='2'/>
</features>
<cpu mode='custom' match='exact'>
<model fallback='allow'>cortex-a15</model>
</cpu>
<clock offset='utc'/>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>restart</on_crash>
<devices>
<emulator>/usr/local/bin/qemu-system-arm</emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2'/>
<source
file='/home/abologna/.local/share/libvirt/images/f25-armv7l.qcow2'/>
<target dev='sda' bus='scsi'/>
<address type='drive' controller='0' bus='0'
target='0' unit='0'/>
</disk>
<controller type='scsi' index='0' model='virtio-scsi'>
<address type='pci' domain='0x0000' bus='0x02'
slot='0x00' function='0x0'/>
</controller>
<controller type='pci' index='0' model='pcie-root'/>
<controller type='pci' index='1'
model='pcie-root-port'>
<model name='ioh3420'/>
<target chassis='1' port='0x8'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x0' multifunction='on'/>
</controller>
<controller type='pci' index='2'
model='pcie-root-port'>
<model name='ioh3420'/>
<target chassis='2' port='0x9'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x1'/>
</controller>
<controller type='pci' index='3'
model='pcie-root-port'>
<model name='ioh3420'/>
<target chassis='3' port='0xa'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x2'/>
</controller>
<interface type='user'>
<mac address='52:54:00:9a:47:50'/>
<model type='virtio'/>
<address type='pci' domain='0x0000' bus='0x01'
slot='0x00' function='0x0'/>
</interface>
<serial type='pty'>
<target port='0'/>
</serial>
<console type='pty'>
<target type='serial' port='0'/>
</console>
</devices>
</domain>
---
And here's that for my Fedora 25/aarch64 guest:
<domain type='qemu'>
<name>f25-aarch64</name>
<uuid>e3e954ba-5280-4b6b-9bfc-7f944f2c67b2</uuid>
<memory unit='KiB'>2097152</memory>
<currentMemory unit='KiB'>2097152</currentMemory>
<vcpu placement='static'>1</vcpu>
<os>
<type arch='aarch64' machine='virt-2.9'>hvm</type>
<loader readonly='yes'
type='pflash'>/usr/share/edk2/aarch64/QEMU_EFI-pflash.raw</loader>
<nvram>/home/abologna/.config/libvirt/qemu/nvram/f25-aarch64_VARS.fd</nvram>
<boot dev='hd'/>
</os>
<features>
<gic version='2'/>
</features>
<cpu mode='custom' match='exact'>
<model fallback='allow'>cortex-a57</model>
</cpu>
<clock offset='utc'/>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>restart</on_crash>
<devices>
<emulator>/usr/local/bin/qemu-system-aarch64</emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2'/>
<source
file='/home/abologna/.local/share/libvirt/images/f25-aarch64.qcow2'/>
<target dev='sda' bus='scsi'/>
<address type='drive' controller='0' bus='0'
target='0' unit='0'/>
</disk>
<controller type='scsi' index='0' model='virtio-scsi'>
<address type='pci' domain='0x0000' bus='0x02'
slot='0x00' function='0x0'/>
</controller>
<controller type='pci' index='0' model='pcie-root'/>
<controller type='pci' index='1'
model='pcie-root-port'>
<model name='ioh3420'/>
<target chassis='1' port='0x8'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x0' multifunction='on'/>
</controller>
<controller type='pci' index='2'
model='pcie-root-port'>
<model name='ioh3420'/>
<target chassis='2' port='0x9'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x1'/>
</controller>
<controller type='pci' index='3'
model='pcie-root-port'>
<model name='ioh3420'/>
<target chassis='3' port='0xa'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x2'/>
</controller>
<interface type='user'>
<mac address='52:54:00:c3:33:4a'/>
<model type='virtio'/>
<address type='pci' domain='0x0000' bus='0x01'
slot='0x00' function='0x0'/>
</interface>
<serial type='pty'>
<target port='0'/>
</serial>
<console type='pty'>
<target type='serial' port='0'/>
</console>
</devices>
</domain>
[1] Fedora 25/armv7l, plus Fedora 25/aarch64 for comparison
[2] Fedora 24/x86_64 with libvirt 3.0.0; I've tried, in turn,
QEMU master, QEMU 2.6 (as shipped with Fedora) and
upstream QEMU 2.5
--
Andrea Bolognani / Red Hat / Virtualization
10:13 a.m.
On Thu, Feb 16, 2017 at 04:58:52PM +0100, Andrea Bolognani wrote:
On Wed, 2017-02-15 at 09:24 +0000, Daniel P. Berrange wrote:
[...]
> $ virsh start f22-arm32
> error: Failed to start domain f22-arm32
> error: internal error: qemu unexpectedly closed the monitor:
2017-02-15T09:24:03.967648Z qemu-system-arm: -device
ioh3420,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x1: MSI is not
supported by interrupt controller
> 2017-02-15T09:24:03.968154Z qemu-system-arm: -device
ioh3420,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x1: Device
initialization failed
>
> I've not bisected it other than to find it works in 2.5.0 and is
> broken in 3.0.0
I'd like you to share a few additional details:
* What does the guest XML look like after libvirt has
had a change to augment it?
<domain type='qemu'>
<name>f22-arm32</name>
<uuid>a6bc14fb-585b-40b0-a15b-5e19f26079ba</uuid>
<memory unit='KiB'>1048576</memory>
<currentMemory unit='KiB'>1048576</currentMemory>
<vcpu placement='static'>1</vcpu>
<os>
<type arch='armv7l' machine='virt-2.7'>hvm</type>
<boot dev='hd'/>
</os>
<features>
<gic version='3'/>
</features>
<clock offset='utc'/>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>restart</on_crash>
<devices>
<emulator>/usr/bin/qemu-system-arm</emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2'/>
<source file='/home/berrange/VirtualMachines/demo.qcow2'/>
<target dev='sda' bus='scsi'/>
<address type='drive' controller='0' bus='0'
target='0' unit='0'/>
</disk>
<controller type='scsi' index='0' model='virtio-scsi'>
<address type='pci' domain='0x0000' bus='0x02'
slot='0x00' function='0x0'/>
</controller>
<controller type='pci' index='0' model='pcie-root'/>
<controller type='pci' index='1'
model='pcie-root-port'>
<model name='ioh3420'/>
<target chassis='1' port='0x8'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x0' multifunction='on'/>
</controller>
<controller type='pci' index='2'
model='pcie-root-port'>
<model name='ioh3420'/>
<target chassis='2' port='0x9'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x1'/>
</controller>
<controller type='pci' index='3'
model='pcie-root-port'>
<model name='ioh3420'/>
<target chassis='3' port='0xa'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x2'/>
</controller>
<interface type='user'>
<mac address='52:54:00:87:d4:c0'/>
<model type='virtio'/>
<address type='pci' domain='0x0000' bus='0x01'
slot='0x00' function='0x0'/>
</interface>
<serial type='pty'>
<target port='0'/>
</serial>
<console type='pty'>
<target type='serial' port='0'/>
</console>
</devices>
</domain>
* What QEMU command line does libvirt generate based
on said guest XML?
LC_ALL=C
PATH=/home/berrange/.local/bin:/home/berrange/.local/bin:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/home/berrange/.local/bin:/home/berrange/bin
HOME=/home/berrange USER=berrange LOGNAME=berrange QEMU_AUDIO_DRV=none
/usr/bin/qemu-system-arm
-name guest=f22-arm32,debug-threads=on
-S
-object
secret,id=masterKey0,format=raw,file=/home/berrange/.config/libvirt/qemu/lib/domain-1-f22-arm32/master-key.aes
-machine virt-2.7,accel=tcg,usb=off,dump-guest-core=off,gic-version=3
-m 1024
-realtime mlock=off
-smp 1,sockets=1,cores=1,threads=1
-uuid a6bc14fb-585b-40b0-a15b-5e19f26079ba
-display none
-no-user-config
-nodefaults
-chardev
socket,id=charmonitor,path=/home/berrange/.config/libvirt/qemu/lib/domain-1-f22-arm32/monitor.sock,server,nowait
-mon chardev=charmonitor,id=monitor,mode=control
-rtc base=utc
-no-shutdown
-boot strict=on
-device ioh3420,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x1
-device ioh3420,port=0x9,chassis=2,id=pci.2,bus=pcie.0,addr=0x1.0x1
-device ioh3420,port=0xa,chassis=3,id=pci.3,bus=pcie.0,addr=0x1.0x2
-device virtio-scsi-pci,id=scsi0,bus=pci.2,addr=0x0
-drive
file=/home/berrange/VirtualMachines/demo.qcow2,format=qcow2,if=none,id=drive-scsi0-0-0-0
-device
scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0,bootindex=1
-netdev user,id=hostnet0
-device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:87:d4:c0,bus=pci.1,addr=0x0
-serial pty
-msg timestamp=on
char device redirected to /dev/pts/20 (label serial0)
2017-02-16T16:04:43.592233Z qemu-system-arm:
-device ioh3420,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x1: MSI is
not supported by interrupt controller
2017-02-16T16:04:43.592725Z qemu-system-arm:
-device ioh3420,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x1: Device
initialization failed
2017-02-16 16:04:43.595+0000: shutting down, reason=failed
* What QEMU version are you running?
2017-02-16 16:04:43.517+0000: starting up libvirt version: 3.0.0, package: 1.fc25
(Unknown, 2017-01-19-10:16:54, t460), qemu version: 2.7.1(qemu-2.7.1-2.fc25), hostname:
t460
I'm asking because I've just spent some time trying to run
ARM guests[1] on my laptop[2] and I can't reproduce the
failure you're describing, so I need more information to
try and narrow it down.
my favourite type of bug :-)
---
I would expect such an error to pop up simply by running
$ qemu-system-arm -nodefaults -M virt \
-device ioh3420,port=0x8,...
Does that happen on your system?
That gets a segmentation fault !
I didn't realize the mach-virt machine type was not an
aarch64-only thing. Indeed, it's available through
qemu-system-arm too, and the hardware seems to be the
same, eg. running
$ echo -e 'info qtree\nquit\n' | \
qemu-system-$arch -M virt -monitor stdio
yields the same output.
The only difference AFAICT is that qemu-system-arm limits
the selection of CPUs to 32-bit models only, eg. cortex-a15
is available on both but only qemu-system-aarch64 lets you
use cortex-a57.
Yep, makes sense - most of the arm code is shared in QEMU
I know 32-bit UEFI is a thing, because it's used on a bunch
of budget x86 tablet and causes grief and pain to anyone
trying to run Linux on them. However, Fedora only ships
64-bit binaries (edk2-ovmf and edk2-aarch64 packages) so I
can't really try whether an armv7l guest can boot using UEFI.
Does -M Virt require UEFI ? I thought those were orthoganol
choices.
Speaking of booting the guest, how would that work with the
guest XML you're feeding libvirt, exactly? Since you don't
have any sort of firmware, the only way I can see it working
is to to have <kernel>, <initrd> and <cmdline> elements
inside <domain><os>, and libvirt can't possibly figure out
their values for you...
That is correct - it can't boot, it needs kernel/initrd.
I'd be happy if QEMU actually got far enough to tell me
I forgot to give it a kernel or firmware :-)
---
Does it help at all to use
<address type='virtio-mmio'/>
in order to force the the SCSI controller and network
interface to use virtio-mmio instead of virtio-pci?
Yes, that launches QEMU which then ultimately exits with a message
[quote]
Trying to execute code outside RAM or ROM at 0x08000000
This usually means one of the following happened:
(1) You told QEMU to execute a kernel for the wrong machine type, and it crashed on
startup (eg trying to run a raspberry pi kernel on a versatilepb QEMU machine)
(2) You didn't give QEMU a kernel or BIOS filename at all, and QEMU executed a ROM
full of no-op instructions until it fell off the end
(3) Your guest kernel has a bug and crashed by jumping off into nowhere
This is almost always one of the first two, so check your command line and that you are
using the right type of kernel for this machine.
If you think option (3) is likely then you can try debugging your guest with the -d debug
options; in particular -d guest_errors will cause the log to include a dump of the guest
register state at this point.
Execution cannot continue; stopping here.
[/quote]
Clearly item (2) is the cause here - no kernel or firmware
Regards,
Daniel
--
|: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org -o- http://virt-manager.org :|
|: http://entangle-photo.org -o- http://search.cpan.org/~danberr/ :|
8:56 a.m.
On Thu, 2017-02-16 at 16:13 +0000, Daniel P. Berrange wrote:
> I'm asking because I've just spent some time trying to
run
> ARM guests[1] on my laptop[2] and I can't reproduce the
> failure you're describing, so I need more information to
> try and narrow it down.
my favourite type of bug :-)
You mean everyone's ;)
Thanks to the additional information, though, I've managed
to pinpoint the issue:
<features>
<gic version='3'/>
</features>
libvirt is picking GICv3 here because QEMU reports it as a
viable emulated GIC; however, as I understand it the
emulated GICv3 doesn't have MSI support, and without that
PCIe can't work. If you manually switch to GICv2 you should
be able to run the guest succesfully.
We should find a way to detect whether the interrupt
controller will support PCIe, and fall back to using
virtio-mmio when it doesn't. Eric, any ideas about how we
could achieve that?
> I would expect such an error to pop up simply by running
>
> $ qemu-system-arm -nodefaults -M virt \
> -device ioh3420,port=0x8,...
>
> Does that happen on your system?
That gets a segmentation fault !
I've managed to reproduce this one too, with both QEMU
2.7.1 and 2.8.0: running
$ qemu-system-{aarch64,arm} \
-nodefaults \
-M virt \
-device ioh3420
is enough to crash it during GTK+ initialization, but
if you add
-display none
(which libvirt will) if works fine.
The bug seems to have been fixed in master; I would
recommend filing a bug against Fedora to get them to
backport it if possible.
> I know 32-bit UEFI is a thing, because it's used on a bunch
> of budget x86 tablet and causes grief and pain to anyone
> trying to run Linux on them. However, Fedora only ships
> 64-bit binaries (edk2-ovmf and edk2-aarch64 packages) so I
> can't really try whether an armv7l guest can boot using UEFI.
Does -M Virt require UEFI ? I thought those were orthoganol
choices.
They are: I've successfully booted both armv7l and aarch64
mach-virt guests with no UEFI involved.
> Speaking of booting the guest, how would that work with the
> guest XML you're feeding libvirt, exactly? Since you don't
> have any sort of firmware, the only way I can see it working
> is to to have <kernel>, <initrd> and <cmdline> elements
> inside <domain><os>, and libvirt can't possibly figure out
> their values for you...
That is correct - it can't boot, it needs kernel/initrd.
I'd be happy if QEMU actually got far enough to tell me
I forgot to give it a kernel or firmware :-)
Okay, so when you say that it worked with 2.5.0 you really
just mean that libvirt got as far as launching QEMU without
it returning an error right away, not that the guest
actually booted all the way to a shell. That makes sense :)
--
Andrea Bolognani / Red Hat / Virtualization
8:09 a.m.
On Fri, 2017-02-17 at 15:56 +0100, Andrea Bolognani wrote:
libvirt is picking GICv3 here because QEMU reports it as a
viable emulated GIC; however, as I understand it the
emulated GICv3 doesn't have MSI support, and without that
PCIe can't work. If you manually switch to GICv2 you should
be able to run the guest succesfully.
We should find a way to detect whether the interrupt
controller will support PCIe, and fall back to using
virtio-mmio when it doesn't. Eric, any ideas about how we
could achieve that?
Actually, we will probably want to do the opposite, eg. pick
GICv2 over GICv3 if the latter doesn't allow us to use PCIe.
--
Andrea Bolognani / Red Hat / Virtualization
11:54 a.m.
Hi,
On 18/02/2017 15:09, Andrea Bolognani wrote:
On Fri, 2017-02-17 at 15:56 +0100, Andrea Bolognani wrote:
> libvirt is picking GICv3 here because QEMU reports it as a
> viable emulated GIC; however, as I understand it the
> emulated GICv3 doesn't have MSI support, and without that
> PCIe can't work. If you manually switch to GICv2 you should
> be able to run the guest succesfully.
>
> We should find a way to detect whether the interrupt
> controller will support PCIe, and fall back to using
> virtio-mmio when it doesn't. Eric, any ideas about how we
> could achieve that?
Actually, we will probably want to do the opposite, eg. pick
GICv2 over GICv3 if the latter doesn't allow us to use PCIe.
Yes I think the easiest solution is to select the GICv2 + v2m combo to
get the MSI support. This depends on whether the limitations linked to
GICv2 usage are acceptable in your case (max 8 cpus for instance).
Thanks
Eric
--
Andrea Bolognani / Red Hat / Virtualization
3:16 a.m.
On Sun, 2017-02-19 at 18:54 +0100, Auger Eric wrote:
> > We should find a way to detect whether the interrupt
> > controller will support PCIe, and fall back to using
> > virtio-mmio when it doesn't. Eric, any ideas about how we
> > could achieve that?
>
> Actually, we will probably want to do the opposite, eg. pick
> GICv2 over GICv3 if the latter doesn't allow us to use PCIe.
Yes I think the easiest solution is to select the GICv2 + v2m combo to
Not sure how the "combo" part works... I noticed that, if
I start a guest with
-machine virt,gic-version=3
I only get one GIC-related device:
dev: arm-gicv3, id ""
gpio-out "sysbus-irq" 4
gpio-in "" 288
num-cpu = 1 (0x1)
num-irq = 288 (0x120)
revision = 3 (0x3)
has-security-extensions = false
mmio 0000000008000000/0000000000010000
mmio 00000000080a0000/0000000000020000
However, if I use gic-version=2, I get:
dev: arm-gicv2m, id ""
gpio-out "sysbus-irq" 64
base-spi = 48 (0x30)
num-spi = 64 (0x40)
mmio 0000000008020000/0000000000001000
dev: arm_gic, id ""
gpio-out "sysbus-irq" 4
gpio-in "" 288
num-cpu = 1 (0x1)
num-irq = 288 (0x120)
revision = 2 (0x2)
has-security-extensions = false
mmio 0000000008000000/0000000000001000
mmio 0000000008010000/0000000000002000
mmio ffffffffffffffff/0000000000000100
Is that what you're referring to? Do we need to care about
the fact that it's two devices rather than one?
get the MSI support. This depends on whether the limitations linked
to
GICv2 usage are acceptable in your case (max 8 cpus for instance).
I think the advantages of using virtio-pci instead of
virtio-mmio offset the limitations of GICv2, at least in
the default case. Aside from not being able to have more
than 8 vCPUs, what other limitations are we looking at?
Anyway, my question was really: how can we tell whether
a certain gic-version will support PCIe? Is there a way
to ask QEMU for the information, or would we have to
hardcode this knowledge in libvirt?
The latter sounds like it would backfire quite easily,
as I assume the emulated GICv3 not having PCIe support
is only a matter of the relevant code not having been
implemented *yet*, not something that's always going
to be true.
--
Andrea Bolognani / Red Hat / Virtualization
12:57 p.m.
On Mon, 2017-02-20 at 10:16 +0100, Andrea Bolognani wrote:
Anyway, my question was really: how can we tell whether
a certain gic-version will support PCIe? Is there a way
to ask QEMU for the information, or would we have to
hardcode this knowledge in libvirt?
The latter sounds like it would backfire quite easily,
as I assume the emulated GICv3 not having PCIe support
is only a matter of the relevant code not having been
implemented *yet*, not something that's always going
to be true.
I just filed
https://bugzilla.redhat.com/show_bug.cgi?id=1435770
to make sure we don't forget about this.
--
Andrea Bolognani / Red Hat / Virtualization
2802
days inactive
2839
days old
7 comments
3 participants
participants (3)
-
Andrea Bolognani -
Auger Eric -
Daniel P. Berrange