On Thu, Mar 10, 2022 at 3:55 PM Ananyev, Konstantin <[email protected]> wrote: > > Calls to rte_memcpy for 1 < n < 16 could result in unaligned > > loads/stores, which is undefined behaviour according to the C > > standard, and strict aliasing violations. > > > > The code was changed to use a packed structure that allows aliasing > > (using the __may_alias__ attribute) to perform the load/store > > operations. This results in code that has the same performance as the > > original code and that is also C standards-compliant. > > > > Fixes: d35cc1fe6a7a ("eal/x86: revert select optimized memcpy at run-time") > > Cc: [email protected] > > > > Signed-off-by: Luc Pelletier <[email protected]> > Acked-by: Konstantin Ananyev <[email protected]> > Tested-by: Konstantin Ananyev <[email protected]>
Thanks, applied. > As a side note, we probably need to check other similar places in DPDK code. What would be the best way to detect those problematic places? I tried UBsan, and it did report some of the issues fixed with this patch. -- David Marchand
