[PATCH 2/2] lib/graph: rte_malloc for cache-aligned structs

[Stephen Hemminger]

On Tue, 17 Jun 2025 11:52:08 +0100
Marat Khalili <marat.khalili at huawei.com> wrote:

> This was flagged by undefined behaviour sanitizer: struct
> rte_graph_cluster_stats is declared as `__rte_cache_aligned` but was
> allocated using stdlib realloc which caused misaligned allocation. More
> than one test needs to be executed in series in order to reproduce the
> problem using graph_autotest, e.g:
> 
>     app/dpdk-test --no-huge --no-pci -m128 graph_autotest graph_autotest
> 
> First sanitizer message  (similar ones follow):
> 
>     lib/graph/graph_stats.c:209:13: runtime error: member access within
>     misaligned address 0x606000008ea0 for type 'struct
>     rte_graph_cluster_stats', which requires 64 byte alignment
> 
> To fix the issue replace realloc calls with rte_malloc and rte_realloc
> specifying correct alignment, use rte_free to free the result.
> 
> Signed-off-by: Marat Khalili <marat.khalili at huawei.com>

There is a way to get aligned memory,

       #include <stdlib.h>

       int posix_memalign(void **memptr, size_t alignment, size_t size);
       void *aligned_alloc(size_t alignment, size_t size);