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To: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>,
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From: Andreas Ziegler <andreas.ziegler@fau.de>
Subject: Re: [PATCHv2 0/7] eBPF JIT for PPC64
In-Reply-To: <cover.1466612260.git.naveen.n.rao@linux.vnet.ibm.com>
Message-ID: <5774E0FC.7010407@fau.de>
Date: Thu, 30 Jun 2016 11:06:04 +0200
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Hi Naveen,

this patchset makes a change to arch/powerpc/net/Makefile in order to only
compile the previously existing bpf_jit_comp.c if !CONFIG_PPC64, and use
bpf_jit_comp64.c if CONFIG_PPC64 is enabled.

Inside arch/powerpc/net/bpf_jit_comp.c, however, there is still an #ifdef
CONFIG_PPC64 block at line 667 (linux-next of today, i.e., next-20160630):

  #ifdef CONFIG_PPC64
                  /* Function descriptor nastiness: Address + TOC */
                  ((u64 *)image)[0] = (u64)code_base;
                  ((u64 *)image)[1] = local_paca->kernel_toc;
  #endif

>>From my understanding of the code, this #ifdef can now be removed, as there is
no way the file could be compiled with CONFIG_PPC64 enabled. Is this correct?

Best regards,

Andreas