malloc: modify error message for DMA mask check

[dpdk.git] / lib / librte_eal / common / malloc_heap.c

diff --git a/lib/librte_eal/common/malloc_heap.c b/lib/librte_eal/common/malloc_heap.c
index 4997c5e..c2c112a 100644 (file)
--- a/lib/librte_eal/common/malloc_heap.c
+++ b/lib/librte_eal/common/malloc_heap.c
@@ -321,13 +321,44 @@ alloc_pages_on_heap(struct malloc_heap *heap, uint64_t pg_sz, size_t elt_size,
                goto fail;
        }
 
-       if (mcfg->dma_maskbits) {
-               if (rte_mem_check_dma_mask(mcfg->dma_maskbits)) {
+       /*
+        * Once we have all the memseg lists configured, if there is a dma mask
+        * set, check iova addresses are not out of range. Otherwise the device
+        * setting the dma mask could have problems with the mapped memory.
+        *
+        * There are two situations when this can happen:
+        *      1) memory initialization
+        *      2) dynamic memory allocation
+        *
+        * For 1), an error when checking dma mask implies app can not be
+        * executed. For 2) implies the new memory can not be added.
+        */
+       if (mcfg->dma_maskbits &&
+           rte_mem_check_dma_mask(mcfg->dma_maskbits)) {
+               /*
+                * Currently this can only happen if IOMMU is enabled
+                * and the address width supported by the IOMMU hw is
+                * not enough for using the memory mapped IOVAs.
+                *
+                * If IOVA is VA, advice to try with '--iova-mode pa'
+                * which could solve some situations when IOVA VA is not
+                * really needed.
+                */
+               RTE_LOG(ERR, EAL,
+                       "%s(): couldn't allocate memory due to IOVA exceeding limits of current DMA mask\n",
+                       __func__);
+
+               /*
+                * If IOVA is VA and it is possible to run with IOVA PA,
+                * because user is root, give and advice for solving the
+                * problem.
+                */
+               if ((rte_eal_iova_mode() == RTE_IOVA_VA) &&
+                    rte_eal_using_phys_addrs())
                        RTE_LOG(ERR, EAL,
-                               "%s(): couldn't allocate memory due to DMA mask\n",
+                               "%s(): Please try initializing EAL with --iova-mode=pa parameter\n",
                                __func__);
-                       goto fail;
-               }
+               goto fail;
        }
 
        /* add newly minted memsegs to malloc heap */