The original problem was not a bug, but working on it I noticed the SeaBIOS warning: Searching bootorder for: /pci@i0cf8/*@1f,2/drive@0/disk@0 AHCI/0: registering: "AHCI/0: QEMU HARDDISK ATA-7 Hard-Disk (100 GiBytes)" found virtio-blk at 3:0 Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@0/*@0 found virtio-blk at 4:0 Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@1/*@0 found virtio-blk at 5:0 Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@2/*@0 found virtio-blk at 6:0 Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@3/*@0 found virtio-blk at 7:0 Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@4/*@0 found virtio-blk at 8:0 Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@5/*@0 found virtio-blk at 9:0 Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@6/*@0 found virtio-blk at a:0 WARNING - Unable to allocate resource at vp_find_vq:35! fail to find vq for virtio-blk a:0 found virtio-blk at b:0 WARNING - Unable to allocate resource at vp_find_vq:35! fail to find vq for virtio-blk b:0 found virtio-blk at c:0 WARNING - Unable to allocate resource at vp_find_vq:35! fail to find vq for virtio-blk c:0 found virtio-blk at d:0 WARNING - Unable to allocate resource at vp_find_vq:35! fail to find vq for virtio-blk d:0 found virtio-blk at e:0 WARNING - Unable to allocate resource at vp_find_vq:35! fail to find vq for virtio-blk e:0 The issue is not related to Q35 or switches, it reproduces also on pc machines, the only thing that matters is using ~ 12 virtio-blk-pci.
Marcel, with which versions do you see this warning?
(In reply to Fam Zheng from comment #3) > Marcel, with which versions do you see this warning? Latest SeaBIOS should also show this warnings, just attach enough virtio blk devices.
I couldn't reproduce this so far with latest qemu-kvm-rhev-2.6.0-3.el7 and seabios-1.9.1-4.el7. I'm using the script in bug description to generate the command line, with 15 virtio-blk devices: SeaBIOS (version 1.9.1-4.el7) All threads complete. Found 0 lpt ports Found 1 serial ports AHCI controller at 1f.2, iobase fea51000, irq 10 Searching bootorder for: /pci@i0cf8/*@1f,2/drive@2/disk@0 AHCI/2: registering: "DVD/CD [AHCI/2: QEMU DVD-ROM ATAPI-4 DVD/CD]" PS2 keyboard initialized found virtio-blk at 3:0 pci dev 3:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@0/*@0 found virtio-blk at 4:0 pci dev 4:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@1/*@0 found virtio-blk at 5:0 pci dev 5:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@2/*@0 found virtio-blk at 6:0 pci dev 6:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@3/*@0 found virtio-blk at 7:0 pci dev 7:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@4/*@0 found virtio-blk at 8:0 pci dev 8:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@5/*@0 found virtio-blk at 9:0 pci dev 9:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@6/*@0 found virtio-blk at a:0 pci dev a:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@7/*@0 found virtio-blk at b:0 pci dev b:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@8/*@0 found virtio-blk at c:0 pci dev c:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@9/*@0 found virtio-blk at d:0 pci dev d:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@a/*@0 found virtio-blk at e:0 pci dev e:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@b/*@0 found virtio-blk at f:0 pci dev f:0 using legacy (0.9.5) virtio mode Searching bootorder for: /pci@i0cf8/pci-bridge@3/pci-bridge@0/pci-bridge@c/*@0 All threads complete.
(In reply to Marcel Apfelbaum from comment #1) > The original problem was not a bug, but working on it I noticed the SeaBIOS > warning: > WARNING - Unable to allocate resource at vp_find_vq:35! > fail to find vq for virtio-blk a:0 > found virtio-blk at b:0 > The issue is not related to Q35 or switches, it reproduces also on pc > machines, the only thing that matters is using ~ 12 virtio-blk-pci. Yes, it's seabios running out of memory, and given the real mode constrains there is no easy way out. Up to 8 virtio-blk devices are documented as supported. If you get 12 everything is fine. If you need more disks use OVMF or virtio-scsi. If you just need some virtio pcie device for bridge testing pick something else.
*** Bug 1326258 has been marked as a duplicate of this bug. ***