Bug 206711 - Export linux_ioctl_{,un}register_handler from linux64 for x11/nvidia-driver
Summary: Export linux_ioctl_{,un}register_handler from linux64 for x11/nvidia-driver
Status: New
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: CURRENT
Hardware: Any Any
: --- Affects Only Me
Assignee: Alexey Dokuchaev
Keywords: needs-qa, patch
Depends on:
Reported: 2016-01-28 13:54 UTC by Jan Beich
Modified: 2017-12-15 05:33 UTC (History)
7 users (show)

See Also:
jbeich: maintainer-feedback? (emulation)

[workaround] nvidia linux_ioctl global handler (for both linux and linux64) (1.52 KB, patch)
2016-01-28 13:54 UTC, Jan Beich
no flags Details | Diff

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Description Jan Beich freebsd_committer 2016-01-28 13:54:28 UTC
Created attachment 166235 [details]
[workaround] nvidia linux_ioctl global handler (for both linux and linux64)

(In reply to ohartman from bug 201340 comment #17)
> on CURRENT amd64 I would at least expect linux64.ko

nvidia-driver requires kernel to provide linux_ioctl_{,un}register_handler to allow linux userland access /dev/nvidia*. According to /sys/modules/linux/Makefile the symbol is only exported for 32bit version. Obviously, linux64 needs to export 64bit symbol. And its not possible to export by building into kernel: option COMPAT_LINUX doesn't exist on amd64.

How to make 64bit OpenGL apps work with nvidia & linuxulator:
1. Switch to 64bit linux_base or populate manually (I've used CentOS 7)
2. Apply *attached* patch and rebuild kernel or just linux* modules
3. Disable linux_ioctl handler in nvidia-driver (i.e. rebuild with LINUX=off)
4. Install 64bit linux driver under /compat/linux
5. Remove sbin/nvidia-modprobe binary to enable userland fallback (as used by FreeBSD driver)

CUDA 64bit may still not work e.g.,

  $ export PATH=/compat/linux/bin:/usr/local/cuda/bin:$PATH
  $ nvcc -o foo -m32 -lcuda a.c
  $ nvcc -o bar -lcuda a.c

  $ ./foo
  $ ./bar
  cuInit failed: 999

  $ cat a.c
  #include <cuda.h>
  #include <stdio.h>

  int main()
      CUresult r = cuInit(0);
      if (r != CUDA_SUCCESS) {
          printf("cuInit failed: %d\n", r);
          return 1;
      return 0;
Comment 1 Jan Beich freebsd_committer 2016-01-28 14:45:51 UTC
Move to canonical assignee.
Comment 2 Dmitry Chagin freebsd_committer 2016-02-22 19:14:57 UTC
nvidia-driver install ioctl_handler, please, look to nvidia_linux_init/nvidia_linux_exit pair that called from nvidia_modevent().

as far as I can see, nvidia driver does not support 64 bit Linuxulator, so nvidia_linux_init() not called for linux64 module. also nvidia driver does not install 64 bit linux libs.
this should be fixed
Comment 3 Jan Beich freebsd_committer 2016-02-23 14:28:11 UTC
(In reply to Dmitry Chagin from comment #2)
The patch here is the result of failed attempt to register 64bit |struct linux_ioctl_handler| from within nvidia-driver. All in-tree kernel modules register only 32bit ioctls, the rest is done by linux64 (drm2, v4l2, console, etc). How do you expect ports drivers to support linux64 without examples?

  $ nm -A /boot/kernel/*.ko | fgrep ioctl_register_handler
  /boot/kernel/amr_linux.ko:                  U linux_ioctl_register_handler
  /boot/kernel/ipmi_linux.ko:                 U linux_ioctl_register_handler
  /boot/kernel/linux.ko:     0000000000009480 t linux_ioctl_register_handler
  /boot/kernel/linux64.ko:   00000000000093e0 t linux_ioctl_register_handler
  /boot/kernel/mfi_linux.ko:                  U linux_ioctl_register_handler
  /boot/kernel/mrsas_linux.ko:                U linux_ioctl_register_handler

nvidia_linux.c doesn't have much MD code but the following has no effect even on the hashsum of its object file.

  --- src/nvidia/nvidia_linux.c~
  +++ src/nvidia/nvidia_linux.c
  @@ -18,13 +18,8 @@
   #define LINUX_IOCTL_NVIDIA_MIN 0x4600
   #define LINUX_IOCTL_NVIDIA_MAX 0x46ff

  -#if defined(NVCPU_X86)
   #include "machine/../linux/linux.h"
   #include "machine/../linux/linux_proto.h"
  -#elif defined(NVCPU_X86_64)
  -#include "machine/../linux32/linux.h"
  -#include "machine/../linux32/linux32_proto.h"

   #include <compat/linux/linux_ioctl.h>
Comment 4 Jan Beich freebsd_committer 2016-04-19 08:17:01 UTC
Andy, can you confirm this bug needs to be fixed before nvidia-driver can support linux64 (64bit linuxulator) available since FreeBSD 10.3-RELEASE ?
Comment 5 Andy Ritger 2016-04-19 15:44:30 UTC
Sorry, I admit I haven't looked at 64-bit Linuxulator support.

Certainly, 64-bit Linux user-space NVIDIA driver components will make ioctls on /dev/nvidia* device files, and we expect those ioctls to be routed to the NVIDIA FreeBSD kernel drivers.  But, I don't know off hand what that plumbing looks like.

I can try to take a look...
Comment 6 Henry Hu 2017-12-15 05:33:42 UTC
Any update on this problem? New CUDA (>7.0) only provides 64-bit libraries, so supporting 64 bit linuxulator is required for using recent CUDA programs.