[PATCH v7] eal: fix rte_memcpy strict aliasing/alignment bugs

[David Marchand]

On Thu, Apr 7, 2022 at 5:32 PM David Marchand <david.marchand at redhat.com> wrote:
>
> On Thu, Apr 7, 2022 at 5:24 PM David Marchand <david.marchand at redhat.com> wrote:
> >
> > On Thu, Mar 10, 2022 at 3:55 PM Ananyev, Konstantin
> > <konstantin.ananyev at intel.com> 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")
>
> Actually, looking again at the history, it fixes:
> Fixes: f5472703c0bd ("eal: optimize aligned memcpy on x86")

Nop, that's probably even older, could you double check?
I'll hold on pushing this fix.


-- 
David Marchand