[Bug 2078773] Re: Missing devices nodes for AMD Instinct MI300 card when installed along with integrated display

Verified linux-oem-6.11/noble-proposed version 6.11.0-1007.7.

** Tags removed: verification-needed-noble-linux-oem-6.11
** Tags added: verification-done-noble-linux-oem-6.11

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https://bugs.launchpad.net/bugs/2078773

Title:
Missing devices nodes for AMD Instinct MI300 card when installed along
with integrated display

Status in HWE Next:
New
Status in linux package in Ubuntu:
Fix Committed
Status in linux-oem-6.11 package in Ubuntu:
Invalid
Status in linux source package in Noble:
Invalid
Status in linux-oem-6.11 source package in Noble:
Fix Committed
Status in linux source package in Oracular:
Fix Committed
Status in linux-oem-6.11 source package in Oracular:
Invalid

Bug description:
[SRU Justification]

BugLink: https://bugs.launchpad.net/bugs/2078773

[Impact]

Missing devices nodes for AMD Instinct MI300 card when installed along
with integrated display.

[Fix]

* https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v6.12-rc1&id=5fbca8b48b3050ae7fb611a8b09af60012ed6de1 ("drm: Use XArray instead of IDR for minors")
* https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v6.12-rc1&id=45c4d994b82b08f0ce5eb50f8da29379c92a391e ("accel: Use XArray instead of IDR for minors")
* https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v6.12-rc1&id=071d583e01c88272f6ff216d4f867f8f35e94d7d ("drm: Expand max DRM device number to full MINORBITS")

[Test Case]

When enabled, additional drm devices will become available:
```
root123@g593-sx1:~$ ls -l /sys/class/drm/
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card10 -> ../../devices/platform/amdgpu_xcp_7/drm/card10
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card11 -> ../../devices/platform/amdgpu_xcp_8/drm/card11
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card12 -> ../../devices/platform/amdgpu_xcp_9/drm/card12
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card13 -> ../../devices/platform/amdgpu_xcp_10/drm/card13
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card14 -> ../../devices/platform/amdgpu_xcp_11/drm/card14
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card15 -> ../../devices/platform/amdgpu_xcp_12/drm/card15
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card16 -> ../../devices/platform/amdgpu_xcp_13/drm/card16
...
```

[Where problems could occur]

New hardware support. Expect more fixes in need.

[Other Info]

Targeting last supported generic/oem kernels only. Nominated for
oem-6.11, generic-6.11 and unstable.

========== original bug descriptions ==========

An issue has come up with MI300 OEM deployments where, due to the
current limit of 64 drm device nodes in the kernel, MI300 systems with
an integrated display (e.g., mgag200 or ast) fail to light up the
console because the AMD GPU driver has used up all of the drm device
nodes. A patch set recently landed in drm-misc to extend the number of
device nodes. These are the relevant commits:

* https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=5fbca8b48b3050ae7fb611a8b09af60012ed6de1 ("drm: Use XArray instead of IDR for minors")
* https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=45c4d994b82b08f0ce5eb50f8da29379c92a391e ("accel: Use XArray instead of IDR for minors")
* https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=071d583e01c88272f6ff216d4f867f8f35e94d7d ("drm: Expand max DRM device number to full MINORBITS")

When enabled, additional drm devices will become available:
```
root123@g593-sx1:~$ ls -l /sys/class/drm/
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card10 -> ../../devices/platform/amdgpu_xcp_7/drm/card10
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card11 -> ../../devices/platform/amdgpu_xcp_8/drm/card11
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card12 -> ../../devices/platform/amdgpu_xcp_9/drm/card12
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card13 -> ../../devices/platform/amdgpu_xcp_10/drm/card13
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card14 -> ../../devices/platform/amdgpu_xcp_11/drm/card14
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card15 -> ../../devices/platform/amdgpu_xcp_12/drm/card15
lrwxrwxrwx 1 root root 0 Sep 21 00:55 card16 -> ../../devices/platform/amdgpu_xcp_13/drm/card16
...
```

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