Using 'imply AMD_IOMMU_V2' does not guarantee that the driver can link against the exported functions. If the GPU driver is built-in but the IOMMU driver is a loadable module, the kfd_iommu.c file is indeed built but does not work:
x86_64-linux-ld: drivers/gpu/drm/amd/amdkfd/kfd_iommu.o: in function `kfd_iommu_bind_process_to_device': kfd_iommu.c:(.text+0x516): undefined reference to `amd_iommu_bind_pasid' x86_64-linux-ld: drivers/gpu/drm/amd/amdkfd/kfd_iommu.o: in function `kfd_iommu_unbind_process': kfd_iommu.c:(.text+0x691): undefined reference to `amd_iommu_unbind_pasid' x86_64-linux-ld: drivers/gpu/drm/amd/amdkfd/kfd_iommu.o: in function `kfd_iommu_suspend': kfd_iommu.c:(.text+0x966): undefined reference to `amd_iommu_set_invalidate_ctx_cb' x86_64-linux-ld: kfd_iommu.c:(.text+0x97f): undefined reference to `amd_iommu_set_invalid_ppr_cb' x86_64-linux-ld: kfd_iommu.c:(.text+0x9a4): undefined reference to `amd_iommu_free_device' x86_64-linux-ld: drivers/gpu/drm/amd/amdkfd/kfd_iommu.o: in function `kfd_iommu_resume': kfd_iommu.c:(.text+0xa9a): undefined reference to `amd_iommu_init_device' x86_64-linux-ld: kfd_iommu.c:(.text+0xadc): undefined reference to `amd_iommu_set_invalidate_ctx_cb' x86_64-linux-ld: kfd_iommu.c:(.text+0xaff): undefined reference to `amd_iommu_set_invalid_ppr_cb' x86_64-linux-ld: kfd_iommu.c:(.text+0xc72): undefined reference to `amd_iommu_bind_pasid' x86_64-linux-ld: kfd_iommu.c:(.text+0xe08): undefined reference to `amd_iommu_set_invalidate_ctx_cb' x86_64-linux-ld: kfd_iommu.c:(.text+0xe26): undefined reference to `amd_iommu_set_invalid_ppr_cb' x86_64-linux-ld: kfd_iommu.c:(.text+0xe42): undefined reference to `amd_iommu_free_device' Use IS_REACHABLE to only build IOMMU-V2 support if the amd_iommu symbols are reachable by the amdkfd driver. Output a warning if they are not, because that may not be what the user was expecting. Fixes: 64d1c3a43a6f ("drm/amdkfd: Centralize IOMMUv2 code and make it conditional") Reported-by: Arnd Bergmann <a...@arndb.de> Signed-off-by: Felix Kuehling <felix.kuehl...@amd.com> --- drivers/gpu/drm/amd/amdkfd/kfd_iommu.c | 6 ++++++ drivers/gpu/drm/amd/amdkfd/kfd_iommu.h | 9 +++++++-- 2 files changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_iommu.c b/drivers/gpu/drm/amd/amdkfd/kfd_iommu.c index 66bbca61e3ef..9318936aa805 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_iommu.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_iommu.c @@ -20,6 +20,10 @@ * OTHER DEALINGS IN THE SOFTWARE. */ +#include <linux/kconfig.h> + +#if IS_REACHABLE(CONFIG_AMD_IOMMU_V2) + #include <linux/printk.h> #include <linux/device.h> #include <linux/slab.h> @@ -355,3 +359,5 @@ int kfd_iommu_add_perf_counters(struct kfd_topology_device *kdev) return 0; } + +#endif diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_iommu.h b/drivers/gpu/drm/amd/amdkfd/kfd_iommu.h index dd23d9fdf6a8..afd420b01a0c 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_iommu.h +++ b/drivers/gpu/drm/amd/amdkfd/kfd_iommu.h @@ -23,7 +23,9 @@ #ifndef __KFD_IOMMU_H__ #define __KFD_IOMMU_H__ -#if defined(CONFIG_AMD_IOMMU_V2_MODULE) || defined(CONFIG_AMD_IOMMU_V2) +#include <linux/kconfig.h> + +#if IS_REACHABLE(CONFIG_AMD_IOMMU_V2) #define KFD_SUPPORT_IOMMU_V2 @@ -46,6 +48,9 @@ static inline int kfd_iommu_check_device(struct kfd_dev *kfd) } static inline int kfd_iommu_device_init(struct kfd_dev *kfd) { +#if IS_MODULE(CONFIG_AMD_IOMMU_V2) + WARN_ONCE(1, "iommu_v2 module is not usable by built-in KFD"); +#endif return 0; } @@ -73,6 +78,6 @@ static inline int kfd_iommu_add_perf_counters(struct kfd_topology_device *kdev) return 0; } -#endif /* defined(CONFIG_AMD_IOMMU_V2) */ +#endif /* IS_REACHABLE(CONFIG_AMD_IOMMU_V2) */ #endif /* __KFD_IOMMU_H__ */ -- 2.30.0 _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel