On Wed, 2017-04-12 at 20:08 -0700, Alexei Starovoitov wrote: > it's really llvm bug that i need fix. It's plain broken > to generate what effectively is nop insn for march=bpfeb > My only excuse that when that code was written llvm had only > march=bpfel. > bpfeb was added much later.
So I'm confused now. Is bpf intended to be endian-independent or not? It sounded at first like it was, even if I have a hard time imagining how that would even work. > > #define be32_to_cpu bswap32 > > or > > #define be32_to_cpu(x) (x) > > depending on the build architecture, I guess. > > yeah. that's what we should have in bpf_helpers.h But that sounds more like it isn't. > ntoh is enough for any networking code, > so I guess we can live without real bswap insn. Well, my reason for asking this is that wireless actually as a little- endian wire protocol, unlike other network stuff :) (Even at a bit level it's defined to transfer the LSB first, but that doesn't really get visible at the level of the CPU that can only address bytes.) johannes
