I try to make VGA pass through works, but always failed.
I can make KVM+OVFM work, but for legacy mode, my Nvidia card never successful pass through to vm.
something out of expect:
1. As expect, drm should disable, but glxinfo show direct rendering is yes
2. disable_vga_mem was called, but no effect
dome dmesg output:
dmesg|grep vgaarb
[ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-4.1.6 root=UUID=728f9f82-2c79-4054-8b66-df6b92623d52 ro quiet intel_iommu=on,igfx_off i915.enable_hd_vgaarb=1 enable_hd_vgaarb=1 kvm.allow_unsafe_assigned_interrupts=1 allow_unsafe_assigned_interrupts=1 blacklist.nouveau=1
[ 0.000000] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-4.1.6 root=UUID=728f9f82-2c79-4054-8b66-df6b92623d52 ro quiet intel_iommu=on,igfx_off i915.enable_hd_vgaarb=1 enable_hd_vgaarb=1 kvm.allow_unsafe_assigned_interrupts=1 allow_unsafe_assigned_interrupts=1 blacklist.nouveau=1
[ 0.168279] vgaarb: setting as boot device: PCI:0000:00:02.0
[ 0.168280] vgaarb: device added: PCI:0000:00:02.0,decodes=io+mem,owns=io+mem,locks=none
[ 0.168283] vgaarb: device added: PCI:0000:01:00.0,decodes=io+mem,owns=io+mem,locks=none
[ 0.168284] vgaarb: loaded
[ 0.168284] vgaarb: bridge control possible 0000:01:00.0
[ 0.168285] vgaarb: no bridge control possible 0000:00:02.0
[ 18.470036] vgaarb: device changed decodes: PCI:0000:00:02.0,olddecodes=io+mem,decodes=io:owns=io+mem
dmesg|grep drm
[ 17.640797] [drm] Initialized drm 1.1.0 20060810
[ 18.457550] [drm] Memory usable by graphics device = 2048M
[ 18.457555] fb: switching to inteldrmfb from simple
[ 18.457659] [drm] Replacing VGA console driver
[ 18.464174] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[ 18.464175] [drm] Driver supports precise vblank timestamp query.
[ 18.471443] [drm] Initialized i915 1.6.0 20150327 for 0000:00:02.0 on minor 0
[ 18.494301] fbcon: inteldrmfb (fb0) is primary device
[ 18.537278] i915 0000:00:02.0: fb0: inteldrmfb frame buffer device
dmesg|grep iommu
[ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-4.1.6 root=UUID=728f9f82-2c79-4054-8b66-df6b92623d52 ro quiet intel_iommu=on,igfx_off i915.enable_hd_vgaarb=1 enable_hd_vgaarb=1 kvm.allow_unsafe_assigned_interrupts=1 allow_unsafe_assigned_interrupts=1 blacklist.nouveau=1
[ 0.000000] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-4.1.6 root=UUID=728f9f82-2c79-4054-8b66-df6b92623d52 ro quiet intel_iommu=on,igfx_off i915.enable_hd_vgaarb=1 enable_hd_vgaarb=1 kvm.allow_unsafe_assigned_interrupts=1 allow_unsafe_assigned_interrupts=1 blacklist.nouveau=1
congzhang@debian:~/projects/linux-4.1.6$ dmesg|grep -i iommu
[ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-4.1.6 root=UUID=728f9f82-2c79-4054-8b66-df6b92623d52 ro quiet intel_iommu=on,igfx_off i915.enable_hd_vgaarb=1 enable_hd_vgaarb=1 kvm.allow_unsafe_assigned_interrupts=1 allow_unsafe_assigned_interrupts=1 blacklist.nouveau=1
[ 0.000000] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-4.1.6 root=UUID=728f9f82-2c79-4054-8b66-df6b92623d52 ro quiet intel_iommu=on,igfx_off i915.enable_hd_vgaarb=1 enable_hd_vgaarb=1 kvm.allow_unsafe_assigned_interrupts=1 allow_unsafe_assigned_interrupts=1 blacklist.nouveau=1
[ 0.000000] Intel-IOMMU: enabled
[ 0.000000] Intel-IOMMU: disable GFX device mapping
[ 0.022861] dmar: IOMMU 0: reg_base_addr fed90000 ver 1:0 cap c0000020660462 ecap f0101a
[ 0.022866] dmar: IOMMU 1: reg_base_addr fed91000 ver 1:0 cap d2008020660462 ecap f010da
[ 0.022869] IOAPIC id 8 under DRHD base 0xfed91000 IOMMU 1
[ 0.453609] IOMMU: dmar1 using Queued invalidation
[ 0.453611] IOMMU: Setting RMRR:
[ 0.453622] IOMMU: Setting identity map for device 0000:00:14.0 [0x8de7b000 - 0x8de89fff]
[ 0.453647] IOMMU: Setting identity map for device 0000:00:1a.0 [0x8de7b000 - 0x8de89fff]
[ 0.453667] IOMMU: Setting identity map for device 0000:00:1d.0 [0x8de7b000 - 0x8de89fff]
[ 0.453680] IOMMU: Prepare 0-16MiB unity mapping for LPC
[ 0.453687] IOMMU: Setting identity map for device 0000:00:1f.0 [0x0 - 0xffffff]
[ 0.463406] AMD IOMMUv2 functionality not available on this system
glxinfo|head
name of display: :0
display: :0 screen: 0
direct rendering: Yes
server glx vendor string: SGI
server glx version string: 1.4
server glx extensions:
GLX_ARB_multisample, GLX_EXT_import_context, GLX_EXT_texture_from_pixmap,
GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_MESA_copy_sub_buffer,
GLX_OML_swap_method, GLX_SGIS_multisample, GLX_SGIX_fbconfig,
GLX_SGIX_pbuffer, GLX_SGI_make_current_read
sudo cat /dev/vga_arbiter |head -2
count:2,PCI:0000:00:02.0,decodes=io,owns=io+mem,locks=none(0:0)
count:2,PCI:0000:00:02.0,decodes=io,owns=io+mem,locks=none(0:0)
lspci -vnn
01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GK106 [GeForce GTX 660] [10de:11c0] (rev a1) (prog-if 00 [VGA controller])
Subsystem: Gigabyte Technology Co., Ltd Device [1458:354e]
Flags: bus master, fast devsel, latency 0, IRQ 255
Memory at f6000000 (32-bit, non-prefetchable) [size=16M]
Memory at e0000000 (64-bit, prefetchable) [size=128M]
Memory at e8000000 (64-bit, prefetchable) [size=32M]
I/O ports at e000 [size=128]
Expansion ROM at f7000000 [disabled] [size=512K]
Capabilities: <access denied>
01:00.1 Audio device [0403]: NVIDIA Corporation GK106 HDMI Audio Controller [10de:0e0b] (rev a1)
Subsystem: Gigabyte Technology Co., Ltd Device [1458:354e]
Flags: bus master, fast devsel, latency 0, IRQ 17
Memory at f7080000 (32-bit, non-prefetchable) [size=16K]
Capabilities: <access denied>
Kernel driver in use: snd_hda_intel
dmesg|grep monkey(myself log)
[ 18.470027] ---monkey---ret = intel_fbdev_init(dev);---monkey---begin--i915_disable_vga_mem(dev);---monkey--- /* Disable VGA memory on Intel HD */
[ 18.470038] ---monkey--- run/* Disable VGA memory on Intel HD */---monkey---end--i915_disable_vga_mem(dev);
my version(which not work as expect and has some mor log) of vgaarb(for debian testing kernel 4.1.6) was attatched!
any help or advice will be very appreciate,
Thanks,
Cong