Error while running the AMDGPU unit tests with ARCH=um

How to reproduce?

➜ ./tools/testing/kunit/kunit.py run --kunitconfig=drivers/gpu/drm/amd/display/amdgpu_dm/tests/ --kconfig_add CONFIG_VIRTIO_UML=y --kconfig_add CONFIG_UML_PCI_OVER_VIRTIO=y

Error

ERROR:root:In file included from ../arch/x86/um/asm/processor.h:41,
                 from ../include/linux/spinlock_up.h:8,
                 from ../include/linux/spinlock.h:95,
                 from ../include/linux/mmzone.h:8,
                 from ../include/linux/gfp.h:6,
                 from ../include/linux/slab.h:15,
                 from ../drivers/gpu/drm/amd/amdgpu/../pm/powerplay/inc/pp_debug.h:35,
                 from ../drivers/gpu/drm/amd/amdgpu/../pm/powerplay/hwmgr/smu7_hwmgr.c:23:
../drivers/gpu/drm/amd/amdgpu/../pm/powerplay/hwmgr/smu7_hwmgr.c: In function ‘intel_core_rkl_chk’:
../arch/um/include/asm/processor-generic.h:103:19: error: called object is not a function or function pointer
  103 | #define cpu_data (&boot_cpu_data)
      |                  ~^~~~~~~~~~~~~~~
../drivers/gpu/drm/amd/amdgpu/../pm/powerplay/hwmgr/smu7_hwmgr.c:1742:34: note: in expansion of macro ‘cpu_data’
 1742 |         struct cpuinfo_x86 *c = &cpu_data(0);
      |                                  ^~~~~~~~
../drivers/gpu/drm/amd/amdgpu/../pm/powerplay/hwmgr/smu7_hwmgr.c:1744:18: error: invalid use of undefined type ‘struct cpuinfo_x86’
 1744 |         return (c->x86 == 6 && c->x86_model == INTEL_FAM6_ROCKETLAKE);
      |                  ^~
../drivers/gpu/drm/amd/amdgpu/../pm/powerplay/hwmgr/smu7_hwmgr.c:1744:33: error: invalid use of undefined type ‘struct cpuinfo_x86’
 1744 |         return (c->x86 == 6 && c->x86_model == INTEL_FAM6_ROCKETLAKE);
      |                                 ^~
../drivers/gpu/drm/amd/amdgpu/../pm/powerplay/hwmgr/smu7_hwmgr.c:1748:1: error: control reaches end of non-void function [-Werror=return-type]
 1748 | }
      | ^
cc1: some warnings being treated as errors

changed the description

Houve essa discussão este ano: https://lore.kernel.org/lkml/20220218075727.2737623-1-davidgow@google.com/T/ E acredito que a solução proposta não foi aceita no fim das contas .

Creio que, naquele momento, realmente, o pessoal da AMD não viu a necessidade de dar suporte a UML. Mas talvez, com a justificativa que será utilizado para rodar testes, esses patches poderiam ir para frente. Não sei, mas talvez, valesse a pena trazer isso à tona novamente.

added AMDGPU label

mentioned in commit a9333bd3

assigned to @mairacanal