[PATCH] drm/amdkfd: flag added to handle errors from svm validate and map

[Alex Sierra]

If a return error is raised during validation and mapping of a
prange, this flag is set. It is a rare occurrence, but it could happen
when `amdgpu_hmm_range_get_pages_done` returns true. In such cases,
the caller should retry. However, it is important to ensure that the
prange is updated correctly during the retry.

Signed-off-by: Alex Sierra <alex.sie...@amd.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 3 ++-
 drivers/gpu/drm/amd/amdkfd/kfd_svm.h | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c 
b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index fcfde9140bce..910c0269598a 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -823,7 +823,7 @@ svm_range_is_same_attrs(struct kfd_process *p, struct 
svm_range *prange,
                }
        }
 
-       return true;
+       return !prange->is_error_flag;
 }
 
 /**
@@ -1657,6 +1657,7 @@ static int svm_range_validate_and_map(struct mm_struct 
*mm,
 unreserve_out:
        svm_range_unreserve_bos(&ctx);
 
+       prange->is_error_flag = !!r;
        if (!r)
                prange->validate_timestamp = ktime_get_boottime();
 
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.h 
b/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
index 7a33b93f9df6..b716d4bf7ee0 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
@@ -133,6 +133,7 @@ struct svm_range {
        DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
        bool                            validated_once;
        bool                            mapped_to_gpu;
+       bool                            is_error_flag;
 };
 
 static inline void svm_range_lock(struct svm_range *prange)
-- 
2.32.0