** Also affects: linux (Ubuntu)
   Importance: Undecided
       Status: New

** Changed in: linux (Ubuntu)
     Assignee: (unassigned) => Leo Lin (0xff07)

** Changed in: linux-oem-7.0 (Ubuntu)
     Assignee: (unassigned) => Leo Lin (0xff07)

** Description changed:

  [ Impact ]
  
  The amdgpu probing sequence can fail for any multitude of reasons
  (missing firmware, missing NPI support, unexpected hardware response).
  
  Ideally; we would have all NPI support in Ubuntu at product launch, but
  due to kernel schedule this isn't always feasible; particularly for
  dGPUs.
  
  For missing NPI support on dGPU specifically we want to be able to
  identify the system though so that we can potentially offer DKMS package
  from amdgpu-install script.
  
  To support this need there are changes introduced that will export IP
  discovery information to userspace even during probe failure.
  
  [ Fix ]
  
  The major patchsets are:
  
  1. drm/amdgpu: Export ip_discovery sysfs on probe failure[1]: in linux-next 
402e04f11ff7
  2. drm/amdgpu: clean up discovery and preempt sysfs entries on shutdown[2]: 
in linux-next 7de02fe95312
  3. drm/amdgpu: don't free standalone ip_discovery sysfs in sysfs_fini[3]: in 
linux-next 26373c719455
  
  And their dependent patches. See additional information.
  
  [ Test plan ]
  
  On APU/dGPU already supported by Ubuntu out-of-the-box:
  
      1) Remove a GPU firmware from /lib/firmware.
      2) Reboot system
      3) Verify amdgpu shows probe error
      4) Verify that IP discovery info in sysfs
      5) Unload amdgpu
      6) Restore GPU firmware
      7) reload amdgpu
      8) Verify works
  
  On new APU/dGPU
  
     1) Verify amdgpu shows probe error
     2) Verify that IP discovery info in sysfs
  
  [ Where problems could occur]
  
  This changes amdgpu module load/unload behaviors, and internal
  implementation of some of its sysfs files. Bugs in those implementation
  may impact tools actively reading those sysfs files (likely, various
  AMD's own tools), or load/unload amdgpu module.
  
  [ Additional information ]
  
  [1] 
https://lore.kernel.org/amd-gfx/[email protected]/
  [2] 
https://lore.kernel.org/amd-gfx/[email protected]/
  [3] 
https://lore.kernel.org/amd-gfx/[email protected]/
  
  The full patch list to support this on 7.0-based kernel:
  
  ```
  drm/amdgpu: don't free standalone ip_discovery sysfs in sysfs_fini
  drm/amdgpu: clean up discovery and preempt sysfs entries on shutdown
  drm/amdgpu: Export ip_discovery sysfs on probe failure
  drm/amdgpu: Fix discovery offset check under VF
  drm/amdgpu: fix IP discovery v0 handling
+ drm/amdgpu: Add size guard before copy discovery binary
+ drm/amdgpu: use DISCOVERY_TMR_SIZE in ACPI TMR fallback 
  drm/amdgpu: Avoid NULL dereference in discovery topology coredump path v3
  drm/amdgpu: fallback to default discovery offset/size in sriov guest
  drm/amdgpu: New interface to get IP discovery binary v3
  drm/amdgpu/discovery: use common function to check discovery table
  drm/amdgpu/discovery: support new discovery binary header
  drm/amdgpu: include ip discovery data in devcoredump
  ```

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https://bugs.launchpad.net/bugs/2158690

Title:
  [SRU] Export IP discovery even if amdgpu probe fails

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