Hi, >> Yes. Reason I ask is because q35 is adding bridges by default now. >> Would it be possible to only add them if requested on command line by user >> instead? I realize some guests expect devices at specific slots >> but this does not apply to bridges I think? > > I just tried out getting rid of the bridges by default.
That clearly raises the question which devices should be created automatically by -M q35. I think the devices which are part of the ich9 chipset should be there by default. /me looks at my laptop which happens to have a ich9 chipset. > So 'lspci' goes from: > > 00:00.0 Host bridge: Intel Corporation 82G33/G31/P35/P31 Express DRAM > Controller Keep. > 00:01.0 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) That looks bogous. Drop. > 00:02.0 VGA compatible controller: Cirrus Logic GD 5446 Our default vga. > 00:03.0 Ethernet controller: Intel Corporation 82540EM Gigabit Ethernet > Controller (rev 03) Real ich9 has the e1000 @ 00:19.0, so it would make sense to place one there. Adding a default nic will probably create some headache though, so maybe better don't. > 00:17.0 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:18.0 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) Looks bogous too, drop. > 00:1c.0 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:1c.1 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:1c.2 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:1c.3 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) Real ich9 has these, keep. > 00:1c.4 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) > 00:1c.5 PCI bridge: Intel Corporation 5500 Non-Legacy I/O Hub PCI Express > Root Port 0 (rev 02) Dunno. Not present in my laptop, other chipset variants might have more pcie ports though ... > 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev 92) Present on real hardware, keep. > 00:1f.0 ISA bridge: Intel Corporation 82801IB (ICH9) LPC Interface Controller > (rev 02) > 00:1f.2 SATA controller: Intel Corporation 82801IR/IO/IH (ICH9R/DO/DH) 6 port > SATA AHCI Controller (rev 02) > 00:1f.3 SMBus: Intel Corporation 82801I (ICH9 Family) SMBus Controller (rev > 02) Keep. > 03:00.0 PCI bridge: Texas Instruments XIO3130 PCI Express Switch (Upstream) > (rev 02) > 04:00.0 PCI bridge: Texas Instruments XIO3130 PCI Express Switch (Downstream) > (rev 01) > 0c:1c.0 PCI bridge: Digital Equipment Corporation DECchip 21154 (rev 05) > 0c:1d.0 PCI bridge: Digital Equipment Corporation DECchip 21154 (rev 05) > 0c:1e.0 PCI bridge: Digital Equipment Corporation DECchip 21154 (rev 05) > 0c:1f.0 PCI bridge: Digital Equipment Corporation DECchip 21154 (rev 05) Drop them. I guess those are just there to simplify bridge device testing. Real hardware also has: 00:1b.0 Audio device: Intel Corporation 82801I (ICH9 Family) HD Audio Controller (rev 03) Emulated by intel-hda. 00:1d.0 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #1 (rev 03) 00:1d.1 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #2 (rev 03) 00:1d.2 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #3 (rev 03) 00:1d.7 USB controller: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #1 (rev 03) We can emulate those too (see docs/docs/ich9-ehci-uhci.cfg). I think we should add audio+usb to q35. cheers, Gerd
