Unknown symbol in module with Linux version 5.15.126-1-pve ?

[bigrck64]

First, thanks for making this VGA driver version for recent kernel :)
My distrib is using kernel Linux version 5.15.126-1-pve, so I compiled it successfully with the following commands:

git clone https://github.com/rhgndf/fl2000_drm
git log -n 10 --oneline
git reset --hard f25190c
make

But when I'm trying to insert it into kernel I got this error

insmod /usr/src/fl2000_drm/fl2000.ko
insmod: ERROR: could not insert module /usr/src/fl2000_drm/fl2000.ko: Unknown symbol in module

Do you have any idea how I can fix this ?
Thanks !

[rhgndf]

Paste the output of dmesg showing the unknown symbol. You probably need to run modprobe drm_shmem_helper.

[bigrck64]

Thanks for replying :)

Here is my dmesg logs:

[517327.186836] fl2000: Unknown symbol drm_kms_helper_poll_fini (err -2)
[517327.186870] fl2000: Unknown symbol drm_gem_fb_end_cpu_access (err -2)
[517327.186888] fl2000: Unknown symbol drm_kms_helper_poll_init (err -2)
[517327.186901] fl2000: Unknown symbol drm_fb_helper_lastclose (err -2)
[517327.186930] fl2000: Unknown symbol drm_atomic_helper_shutdown (err -2)
[517327.186938] fl2000: Unknown symbol drm_gem_simple_kms_cleanup_shadow_fb (err -2)
[517327.186984] fl2000: Unknown symbol drm_atomic_helper_commit (err -2)
[517327.186991] fl2000: Unknown symbol drm_atomic_helper_check (err -2)
[517327.186997] fl2000: Unknown symbol drm_atomic_helper_connector_destroy_state (err -2)
[517327.187023] fl2000: Unknown symbol drm_gem_simple_kms_destroy_shadow_plane_state (err -2)
[517327.187036] fl2000: Unknown symbol drm_mode_config_helper_suspend (err -2)
[517327.187052] fl2000: Unknown symbol drm_atomic_helper_damage_merged (err -2)
[517327.187058] fl2000: Unknown symbol drm_gem_simple_kms_prepare_shadow_fb (err -2)
[517327.187070] fl2000: Unknown symbol drm_gem_fb_create_with_dirty (err -2)
[517327.187121] fl2000: Unknown symbol drm_fbdev_generic_setup (err -2)
[517327.187128] fl2000: Unknown symbol drm_atomic_helper_connector_duplicate_state (err -2)
[517327.187135] fl2000: Unknown symbol drm_simple_display_pipe_init (err -2)
[517327.187156] fl2000: Unknown symbol drm_gem_simple_kms_duplicate_shadow_plane_state (err -2)
[517327.187164] fl2000: Unknown symbol drm_gem_fb_begin_cpu_access (err -2)
[517327.187170] fl2000: Unknown symbol drm_kms_helper_hotplug_event (err -2)
[517327.187184] fl2000: Unknown symbol drm_helper_probe_single_connector_modes (err -2)
[517327.187198] fl2000: Unknown symbol drm_gem_simple_kms_reset_shadow_plane (err -2)
[517327.187205] fl2000: Unknown symbol drm_atomic_helper_connector_reset (err -2)
[517327.187216] fl2000: Unknown symbol drm_mode_config_helper_resume (err -2)

So I try to modprobe drm_shmem_helper

modprobe drm_shmem_helper
modprobe: FATAL: Module drm_shmem_helper not found in directory /lib/modules/5.15.126-1-pve

But I don't have such module :)

find /lib/modules/5.15.126-1-pve |grep drm
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/nouveau
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/nouveau/nouveau.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/i2c
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/i2c/tda998x.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/i2c/tda9950.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/i2c/sil164.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/i2c/ch7006.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/gud
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/gud/gud.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/mgag200
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/mgag200/mgag200.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/drm_vram_helper.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/udl
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/udl/udl.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/bridge
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/bridge/analogix
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/bridge/analogix/analogix_dp.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/drm_kms_helper.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/ast
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/ast/ast.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/vkms
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/vkms/vkms.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/i915
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/i915/gvt
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/i915/gvt/kvmgt.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/i915/i915.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/hyperv
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/hyperv/hyperv_drm.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/scheduler
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/scheduler/gpu-sched.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/amd
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/amd/amdgpu
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/amd/amdgpu/amdgpu.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/virtio
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/virtio/virtio-gpu.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/ttm
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/ttm/ttm.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/drm.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/xen
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/xen/drm_xen_front.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/vgem
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/vgem/vgem.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/qxl
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/qxl/qxl.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/gma500
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/gma500/gma500_gfx.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/repaper.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/bochs.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/ili9486.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/cirrus.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/st7735r.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/hx8357d.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/simpledrm.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/st7586.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/ili9225.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/mi0283qt.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/ili9341.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/tiny/gm12u320.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/drm_ttm_helper.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/drm_mipi_dbi.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/panel
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/panel/panel-widechips-ws2401.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/radeon
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/radeon/radeon.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/vboxvideo
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/vboxvideo/vboxvideo.ko
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/vmwgfx
/lib/modules/5.15.126-1-pve/kernel/drivers/gpu/drm/vmwgfx/vmwgfx.ko

[rhgndf]

You will need to find the modules associated with the functions and modprobe them. Maybe try drm and drm_kms_helper? I didn't need to do that so I'm not sure which modules are needed.

[bigrck64]

Good call, I can now insert the module in kernel !

modprobe drm drm_kms_helper
insmod /usr/src/fl2000_drm/fl2000.ko

dmesg

[698290.893515] usb 2-4: new SuperSpeed USB device number 4 using xhci_hcd
[698290.916595] usb 2-4: config 1 interface 1 altsetting 0 has a duplicate endpoint with address 0x81, skipping
[698290.916604] usb 2-4: config 1 interface 1 altsetting 0 has a duplicate endpoint with address 0x1, skipping
[698290.916608] usb 2-4: config 1 interface 1 altsetting 1 has a duplicate endpoint with address 0x81, skipping
[698290.916612] usb 2-4: config 1 interface 1 altsetting 1 has a duplicate endpoint with address 0x1, skipping
[698290.916616] usb 2-4: config 1 interface 1 altsetting 2 has a duplicate endpoint with address 0x81, skipping
[698290.916620] usb 2-4: config 1 interface 1 altsetting 2 has a duplicate endpoint with address 0x1, skipping
[698290.916624] usb 2-4: config 1 interface 1 altsetting 3 has a duplicate endpoint with address 0x81, skipping
[698290.916627] usb 2-4: config 1 interface 1 altsetting 3 has a duplicate endpoint with address 0x1, skipping
[698290.916631] usb 2-4: config 1 interface 1 altsetting 4 has a duplicate endpoint with address 0x81, skipping
[698290.916634] usb 2-4: config 1 interface 1 altsetting 4 has a duplicate endpoint with address 0x1, skipping
[698290.916638] usb 2-4: config 1 interface 1 altsetting 5 has a duplicate endpoint with address 0x81, skipping
[698290.916642] usb 2-4: config 1 interface 1 altsetting 5 has a duplicate endpoint with address 0x1, skipping
[698290.916646] usb 2-4: config 1 interface 1 altsetting 6 has a duplicate endpoint with address 0x81, skipping
[698290.916649] usb 2-4: config 1 interface 1 altsetting 6 has a duplicate endpoint with address 0x1, skipping
[698290.916655] usb 2-4: New USB device found, idVendor=1d5c, idProduct=2000, bcdDevice= 2.00
[698290.916659] usb 2-4: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[698290.934188] [drm] Initialized fl2000_drm 1.0.1 20181001 for 2-4 on minor 0
[698290.953179] usb 2-4: [drm] Cannot find any crtc or sizes
[698290.953296] usb-storage 2-4:1.3: USB Mass Storage device detected
[698290.953370] usb 2-4: [drm] Cannot find any crtc or sizes
[698290.953412] scsi host6: usb-storage 2-4:1.3
[698291.961025] scsi 6:0:0:0: Direct-Access A001 PQ: 0 ANSI: 4
[698291.961164] sd 6:0:0:0: Attached scsi generic sg1 type 0
[698291.961350] sd 6:0:0:0: [sdb] 2047 4096-byte logical blocks: (8.38 MB/8.00 MiB)
[698291.961471] sd 6:0:0:0: [sdb] Write Protect is off
[698291.961474] sd 6:0:0:0: [sdb] Mode Sense: 03 00 00 00
[698291.961589] sd 6:0:0:0: [sdb] No Caching mode page found
[698291.961592] sd 6:0:0:0: [sdb] Assuming drive cache: write through
[698291.964499] sdb:
[698291.964955] sd 6:0:0:0: [sdb] Attached SCSI disk

[bigrck64]

I got another question :)
Now the driver seems to be ok, is there a way to display the linux console on VGA output ?

[rhgndf]

Not sure what it takes to get this working though. There is fbdev code inside already.

[rhgndf]

I think I might have found a solution for the virtual console issue. Might want to look into the con2fbmap command. From what I see, the syntax is con2fbmap 1 1 to switch to the second framebuffer, which is likely the fl2000, and con2fbmap 1 0 to switch back.

[bigrck64]

Thank you for finding this !
So I installed the con2fbmap binary with the debian package "apt-get install fbset"

But it's not working here:

root@pdm999:/usr/src/fl2000_drm# con2fbmap 1 1
open /dev/fb0: No such file or directory

In fact I don't have any framebuffer active :(

l /dev/fb*
ls: cannot access '/dev/fb*': No such file or directory

There is something wrong with the fl2000 kernel module, it doesn't export his framebuffer into /dev/fb* for me
Here is my dmesg:

[ 717.775504] [drm] Initialized fl2000_drm 1.0.1 20181001 for 4-2 on minor 0
[ 717.793889] usb 4-2: [drm] Cannot find any crtc or sizes
[ 717.793923] usbcore: registered new interface driver fl2000_usb
[ 717.794119] usb 4-2: [drm] Cannot find any crtc or sizes
[ 717.945088] usb 4-2: is sink event 1
[ 717.945163] usb 4-2: interrupt
[ 718.344943] Console: switching to colour frame buffer device 240x67
[ 718.361494] xhci_hcd 0000:2c:00.3: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0011 address=0xfe000000 flags=0x0000]
[ 718.361498] xhci_hcd 0000:2c:00.3: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0011 address=0xfe001000 flags=0x0000]
[ 718.364499] usb 4-2: [drm] fb0: fl2000_drmdrmfb frame buffer device
[ 718.465537] ------------[ cut here ]------------
[ 718.465538] [CRTC:33:crtc-0] vblank wait timed out
[ 718.465547] WARNING: CPU: 3 PID: 7146 at drivers/gpu/drm/drm_atomic_helper.c:1533 drm_atomic_helper_wait_for_vblanks.part.0+0x282/0x290 [drm_kms_helper]
[ 718.465563] Modules linked in: fl2000(O) drm_kms_helper cec rc_core fb_sys_fops syscopyarea sysfillrect sysimgblt uas usb_storage nfsv3 nfs_acl rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs lockd grace fscache netfs ebtable_filter ebtables ip_set ip6table_raw iptable_raw ip6table_filter ip6_tables iptable_filter bpfilter cls_u32 sch_htb nf_tables bonding tls softdog nfnetlink_log nfnetlink ppdev intel_rapl_msr intel_rapl_common edac_mce_amd kvm_amd kvm irqbypass crct10dif_pclmul ghash_clmulni_intel aesni_intel crypto_simd cryptd input_leds rapl wmi_bmof efi_pstore parport_pc pcspkr ccp k10temp parport mac_hid zfs(PO) zunicode(PO) zzstd(O) zlua(O) zavl(PO) icp(PO) zcommon(PO) znvpair(PO) spl(O) vhost_net vhost vhost_iotlb tap ib_iser rdma_cm iw_cm ib_cm ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi nct6775 hwmon_vid drm sunrpc ip_tables x_tables autofs4 btrfs blake2b_generic xor zstd_compress raid6_pq simplefb hid_generic usbkbd usbmouse dm_thin_pool dm_persistent_data
[ 718.465602] dm_bio_prison dm_bufio libcrc32c usbhid hid xhci_pci crc32_pclmul xhci_pci_renesas r8169 i2c_piix4 realtek ahci xhci_hcd libahci wmi gpio_amdpt gpio_generic
[ 718.465609] CPU: 3 PID: 7146 Comm: kworker/3:0 Tainted: P O 5.15.131-2-pve #1
[ 718.465611] Hardware name: Micro-Star International Co., Ltd. MS-7D95/PRO B550M-P GEN3 (MS-7D95), BIOS 1.50 06/27/2023
[ 718.465612] Workqueue: events drm_fb_helper_damage_work [drm_kms_helper]
[ 718.465622] RIP: 0010:drm_atomic_helper_wait_for_vblanks.part.0+0x282/0x290 [drm_kms_helper]
[ 718.465631] Code: 00 00 48 83 c7 08 e8 6d 24 28 c4 45 85 ff 0f 85 c6 fe ff ff 49 8b 54 24 20 41 8b 74 24 60 48 c7 c7 f8 98 2b c1 e8 4d c3 e4 c4 <0f> 0b e9 a9 fe ff ff e8 92 3b ef c4 66 90 0f 1f 44 00 00 f6 46 10
[ 718.465632] RSP: 0018:ffffb123e468bc10 EFLAGS: 00010282
[ 718.465633] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff92369eae0588
[ 718.465634] RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffff92369eae0580
[ 718.465635] RBP: ffffb123e468bc88 R08: 0000000000000026 R09: 0000000088634118
[ 718.465636] R10: ffffffffffffffff R11: 0000000000000001 R12: ffff922f14976638
[ 718.465636] R13: ffff9227c13ad900 R14: 0000000000000000 R15: 0000000000000000
[ 718.465637] FS: 0000000000000000(0000) GS:ffff92369eac0000(0000) knlGS:0000000000000000
[ 718.465638] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 718.465639] CR2: 00000048d77cf800 CR3: 000000010cd90000 CR4: 0000000000750ee0
[ 718.465640] PKRU: 55555554
[ 718.465641] Call Trace:
[ 718.465642]
[ 718.465643] ? show_regs.cold+0x1a/0x1f
[ 718.465647] ? drm_atomic_helper_wait_for_vblanks.part.0+0x282/0x290 [drm_kms_helper]
[ 718.465655] ? __warn+0x8c/0x100
[ 718.465657] ? drm_atomic_helper_wait_for_vblanks.part.0+0x282/0x290 [drm_kms_helper]
[ 718.465665] ? report_bug+0xa4/0xd0
[ 718.465669] ? handle_bug+0x39/0x90
[ 718.465670] ? exc_invalid_op+0x19/0x70
[ 718.465672] ? asm_exc_invalid_op+0x1b/0x20
[ 718.465674] ? drm_atomic_helper_wait_for_vblanks.part.0+0x282/0x290 [drm_kms_helper]
[ 718.465682] ? wait_woken+0x70/0x70
[ 718.465685] drm_atomic_helper_commit_tail+0x75/0x90 [drm_kms_helper]
[ 718.465693] commit_tail+0x10c/0x180 [drm_kms_helper]
[ 718.465701] ? drm_atomic_helper_swap_state+0x20f/0x370 [drm_kms_helper]
[ 718.465709] drm_atomic_helper_commit+0x12b/0x150 [drm_kms_helper]
[ 718.465718] drm_atomic_commit+0x4a/0x60 [drm]
[ 718.465735] drm_atomic_helper_dirtyfb+0x199/0x270 [drm_kms_helper]
[ 718.465744] drm_fb_helper_damage_work+0x1aa/0x340 [drm_kms_helper]
[ 718.465753] process_one_work+0x22b/0x3d0
[ 718.465755] worker_thread+0x53/0x420
[ 718.465757] ? process_one_work+0x3d0/0x3d0
[ 718.465758] kthread+0x12a/0x150
[ 718.465760] ? set_kthread_struct+0x50/0x50
[ 718.465762] ret_from_fork+0x22/0x30
[ 718.465765]
[ 718.465765] ---[ end trace a707933c2fd4d3bc ]---
[ 728.513507] [drm:drm_crtc_commit_wait [drm]] ERROR flip_done timed out
[ 728.513535] [drm:drm_atomic_helper_wait_for_dependencies [drm_kms_helper]] ERROR [CRTC:33:crtc-0] commit wait timed out
root@pdm999:/usr/src/fl2000_drm# l /dev/fb*
ls: cannot access '/dev/fb*': No such file or directory

Question: Do you have on your side one FrameBuffer available in /dev with this kernel module ?
Thanks :)

[bigrck64]

Maybe linux change something with /dev/fb in newer kernel.

With the same hardware + one real graphic nvidia pci card:

• Linux version 5.4.203 = /dev/fb0 available (dmesg: fbcon: nouveaudrmfb (fb0) is primary device)
• Linux version 5.15.107 = no /dev/fb0 (dmesg: nouveau 0000:29:00.0: fb: 1024 MiB DDR3)

EDIT - OK bad idea:

Assuming some form of display is attached, then the kernel DRM subsystem will create a framebuffer. No connected displays, not framebuffer device.
I try to make /dev/fb0 displayed again by adding CONFIG_DRM_KMS_FB_HELPER=y into /boot/config-5.15.131-1-pve, but it's no more working.

Anyway, the /deb/fb0 should spawn when connecting fl2000 with vga adapter, and unfortunatly it's not working here. (see preview dmes)

[rhgndf]

AMD-Vi IO_PAGE_FAULT

See #2. I also have an AMD system but I couldn't reproduce the issue so I'm not sure what's causing the kernel error.

CONFIG_DRM_KMS_FB_HELPER=y

You will need to recompile the kernel for that. I have /dev/fb* on linux kernel 6.6. You could also try kmscon for the console output, which probably works without recompilation.