[dpdk-dev] [PATCH v2 2/2] vdpa/mlx5: fix large VM memory region registration

[Xueming Li]

When VM size larger than 4G(u32) and memory region larger than 4G, the
32 bits GCD function overflow and returned wrong value that resulted
memory registration failed.

This patch calls 64 bits GCD function to avoid overflow.

Fixes: cc07a42da250 ("vdpa/mlx5: prepare memory regions")
Cc: ma...@mellanox.com
Cc: sta...@dpdk.org
Reviewed-by: Matan Azrad <ma...@nvidia.com>

Signed-off-by: Xueming Li <xuemi...@nvidia.com>
---
 drivers/vdpa/mlx5/mlx5_vdpa_mem.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/vdpa/mlx5/mlx5_vdpa_mem.c 
b/drivers/vdpa/mlx5/mlx5_vdpa_mem.c
index 59ce4e891c..a06681b494 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa_mem.c
+++ b/drivers/vdpa/mlx5/mlx5_vdpa_mem.c
@@ -103,15 +103,15 @@ mlx5_vdpa_vhost_mem_regions_prepare(int vid, uint8_t 
*mode, uint64_t *mem_size,
                        size = mem->regions[i].guest_phys_addr -
                                (mem->regions[i - 1].guest_phys_addr +
                                 mem->regions[i - 1].size);
-                       *gcd = rte_get_gcd(*gcd, size);
+                       *gcd = rte_get_gcd64(*gcd, size);
                        klm_entries_num += KLM_NUM_MAX_ALIGN(size);
                }
                size = mem->regions[i].size;
-               *gcd = rte_get_gcd(*gcd, size);
+               *gcd = rte_get_gcd64(*gcd, size);
                klm_entries_num += KLM_NUM_MAX_ALIGN(size);
        }
        if (*gcd > MLX5_MAX_KLM_BYTE_COUNT)
-               *gcd = rte_get_gcd(*gcd, MLX5_MAX_KLM_BYTE_COUNT);
+               *gcd = rte_get_gcd64(*gcd, MLX5_MAX_KLM_BYTE_COUNT);
        if (!RTE_IS_POWER_OF_2(*gcd)) {
                uint64_t candidate_gcd = rte_align64prevpow2(*gcd);
 
-- 
2.33.0