diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index 88cc26e008fce..b085c02b53d0e 100644
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -547,11 +547,6 @@ static inline const struct mlx5_umr_wr *umr_wr(const struct ib_send_wr *wr)
 	return container_of(wr, struct mlx5_umr_wr, wr);
 }
 
-struct mlx5_shared_mr_info {
-	int mr_id;
-	struct ib_umem		*umem;
-};
-
 enum mlx5_ib_cq_pr_flags {
 	MLX5_IB_CQ_PR_FLAGS_CQE_128_PAD	= 1 << 0,
 };
@@ -654,47 +649,69 @@ struct mlx5_ib_dm {
 	atomic64_add(value, &((mr)->odp_stats.counter_name))
 
 struct mlx5_ib_mr {
-	struct ib_mr		ibmr;
-	void			*descs;
-	dma_addr_t		desc_map;
-	int			ndescs;
-	int			data_length;
-	int			meta_ndescs;
-	int			meta_length;
-	int			max_descs;
-	int			desc_size;
-	int			access_mode;
-	unsigned int		page_shift;
-	struct mlx5_core_mkey	mmkey;
-	struct ib_umem	       *umem;
-	struct mlx5_shared_mr_info	*smr_info;
-	struct list_head	list;
-	struct mlx5_cache_ent  *cache_ent;
-	u32 out[MLX5_ST_SZ_DW(create_mkey_out)];
-	struct mlx5_core_sig_ctx    *sig;
-	void			*descs_alloc;
-	int			access_flags; /* Needed for rereg MR */
-
-	struct mlx5_ib_mr      *parent;
-	/* Needed for IB_MR_TYPE_INTEGRITY */
-	struct mlx5_ib_mr      *pi_mr;
-	struct mlx5_ib_mr      *klm_mr;
-	struct mlx5_ib_mr      *mtt_mr;
-	u64			data_iova;
-	u64			pi_iova;
-
-	/* For ODP and implicit */
-	struct xarray		implicit_children;
-	union {
-		struct list_head elm;
-		struct work_struct work;
-	} odp_destroy;
-	struct ib_odp_counters	odp_stats;
-	bool			is_odp_implicit;
+	struct ib_mr ibmr;
+	struct mlx5_core_mkey mmkey;
 
-	struct mlx5_async_work  cb_work;
+	/* User MR data */
+	struct mlx5_cache_ent *cache_ent;
+	struct ib_umem *umem;
+
+	/* This is zero'd when the MR is allocated */
+	struct {
+		/* Used only while the MR is in the cache */
+		struct {
+			u32 out[MLX5_ST_SZ_DW(create_mkey_out)];
+			struct mlx5_async_work cb_work;
+			/* Cache list element */
+			struct list_head list;
+		};
+
+		/* Used only by kernel MRs (umem == NULL) */
+		struct {
+			void *descs;
+			void *descs_alloc;
+			dma_addr_t desc_map;
+			int max_descs;
+			int ndescs;
+			int desc_size;
+			int access_mode;
+
+			/* For Kernel IB_MR_TYPE_INTEGRITY */
+			struct mlx5_core_sig_ctx *sig;
+			struct mlx5_ib_mr *pi_mr;
+			struct mlx5_ib_mr *klm_mr;
+			struct mlx5_ib_mr *mtt_mr;
+			u64 data_iova;
+			u64 pi_iova;
+			int meta_ndescs;
+			int meta_length;
+			int data_length;
+		};
+
+		/* Used only by User MRs (umem != NULL) */
+		struct {
+			unsigned int page_shift;
+			/* Current access_flags */
+			int access_flags;
+
+			/* For User ODP */
+			struct mlx5_ib_mr *parent;
+			struct xarray implicit_children;
+			union {
+				struct work_struct work;
+			} odp_destroy;
+			struct ib_odp_counters odp_stats;
+			bool is_odp_implicit;
+		};
+	};
 };
 
+/* Zero the fields in the mr that are variant depending on usage */
+static inline void mlx5_clear_mr(struct mlx5_ib_mr *mr)
+{
+	memset(mr->out, 0, sizeof(*mr) - offsetof(struct mlx5_ib_mr, out));
+}
+
 static inline bool is_odp_mr(struct mlx5_ib_mr *mr)
 {
 	return IS_ENABLED(CONFIG_INFINIBAND_ON_DEMAND_PAGING) && mr->umem &&
diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c
index db05b0e0a8d7a..ea8f068a6da3e 100644
--- a/drivers/infiniband/hw/mlx5/mr.c
+++ b/drivers/infiniband/hw/mlx5/mr.c
@@ -590,6 +590,8 @@ struct mlx5_ib_mr *mlx5_mr_cache_alloc(struct mlx5_ib_dev *dev,
 		ent->available_mrs--;
 		queue_adjust_cache_locked(ent);
 		spin_unlock_irq(&ent->lock);
+
+		mlx5_clear_mr(mr);
 	}
 	mr->access_flags = access_flags;
 	return mr;
@@ -615,16 +617,14 @@ static struct mlx5_ib_mr *get_cache_mr(struct mlx5_cache_ent *req_ent)
 			ent->available_mrs--;
 			queue_adjust_cache_locked(ent);
 			spin_unlock_irq(&ent->lock);
-			break;
+			mlx5_clear_mr(mr);
+			return mr;
 		}
 		queue_adjust_cache_locked(ent);
 		spin_unlock_irq(&ent->lock);
 	}
-
-	if (!mr)
-		req_ent->miss++;
-
-	return mr;
+	req_ent->miss++;
+	return NULL;
 }
 
 static void detach_mr_from_cache(struct mlx5_ib_mr *mr)
@@ -993,8 +993,6 @@ static struct mlx5_ib_mr *alloc_cacheable_mr(struct ib_pd *pd,
 
 	mr->ibmr.pd = pd;
 	mr->umem = umem;
-	mr->access_flags = access_flags;
-	mr->desc_size = sizeof(struct mlx5_mtt);
 	mr->mmkey.iova = iova;
 	mr->mmkey.size = umem->length;
 	mr->mmkey.pd = to_mpd(pd)->pdn;
diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c
index b103555b1f5d4..d98755e78362f 100644
--- a/drivers/infiniband/hw/mlx5/odp.c
+++ b/drivers/infiniband/hw/mlx5/odp.c
@@ -227,7 +227,6 @@ static void free_implicit_child_mr(struct mlx5_ib_mr *mr, bool need_imr_xlt)
 
 	dma_fence_odp_mr(mr);
 
-	mr->parent = NULL;
 	mlx5_mr_cache_free(mr_to_mdev(mr), mr);
 	ib_umem_odp_release(odp);
 }