Hi Arnd, On Fri, May 14, 2021 at 12:00:53PM +0200, Arnd Bergmann wrote: > Little-endian POWER7 kernels disable > CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS because that is not supported on > the hardware, but the kernel still uses direct load/store for explicti > get_unaligned()/put_unaligned(). > > I assume this is a mistake that leads to power7 having to trap and fix > up all these unaligned accesses at a noticeable performance cost. > > The fix is completely trivial, just remove the file and use the > generic version that gets it right. LE p7 isn't supported (it requires special firmware), and no one uses it anymore, also not for development. It was used for powerpc64le-linux development before p8 was widely available. Segher
