On Fri, May 8, 2015 at 1:38 AM, Will Deacon <will.dea...@arm.com> wrote: >> - imm64 = (u64)insn1.imm << 32 | imm; >> + imm64 = ((u64)(u32)insn1.imm) << 32 | (u64)(u32)imm; > > This seems a bit convoluted to me. Don't you just need to add a (u32) > cast to imm and that's it? The (u64)(u32) looks redundant.
You're right - the second (u64) is redundant; the hope was to make the code easier to understand. It's from the interpreter code in kernel/core/bpf.c, which uses (u64)(u32) as well. >> - BPF_ALU64_IMM(BPF_MOV, R0, 1), >> + BPF_LD_IMM64(R0, 0x1ffffffffLL), >> + BPF_ALU64_IMM(BPF_RSH, R0, 32), /* R0 = 1 */ >> BPF_EXIT_INSN(), > > This hunk should probably be a separate patch, unless you get Alexei's ack > for me to take it via the arm64 tree too. I would be happy to split this into a separate patch if that works better, or simply drop this part. - xi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
