From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F299CC2D0BF for ; Mon, 16 Dec 2019 15:09:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CE33620409 for ; Mon, 16 Dec 2019 15:09:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728183AbfLPPJ6 (ORCPT ); Mon, 16 Dec 2019 10:09:58 -0500 Received: from www62.your-server.de ([213.133.104.62]:51152 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728109AbfLPPJ6 (ORCPT ); Mon, 16 Dec 2019 10:09:58 -0500 Received: from sslproxy01.your-server.de ([88.198.220.130]) by www62.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89_1) (envelope-from ) id 1igs0R-0004Lt-4j; Mon, 16 Dec 2019 16:09:55 +0100 Received: from [2001:1620:665:0:5795:5b0a:e5d5:5944] (helo=linux.fritz.box) by sslproxy01.your-server.de with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1igs0Q-0000NE-Ld; Mon, 16 Dec 2019 16:09:54 +0100 Subject: Re: [PATCH bpf-next v2 6/9] riscv, bpf: provide RISC-V specific JIT image alloc/free To: =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , ast@kernel.org, netdev@vger.kernel.org Cc: linux-riscv@lists.infradead.org, bpf@vger.kernel.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu References: <20191216091343.23260-1-bjorn.topel@gmail.com> <20191216091343.23260-7-bjorn.topel@gmail.com> From: Daniel Borkmann Message-ID: <7ceab77a-92e7-6415-3045-3e16876d4ef8@iogearbox.net> Date: Mon, 16 Dec 2019 16:09:53 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20191216091343.23260-7-bjorn.topel@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-Authenticated-Sender: daniel@iogearbox.net X-Virus-Scanned: Clear (ClamAV 0.101.4/25665/Mon Dec 16 10:52:23 2019) Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On 12/16/19 10:13 AM, Björn Töpel wrote: > This commit makes sure that the JIT images is kept close to the kernel > text, so BPF calls can use relative calling with auipc/jalr or jal > instead of loading the full 64-bit address and jalr. > > The BPF JIT image region is 128 MB before the kernel text. > > Signed-off-by: Björn Töpel > --- > arch/riscv/include/asm/pgtable.h | 4 ++++ > arch/riscv/net/bpf_jit_comp.c | 13 +++++++++++++ > 2 files changed, 17 insertions(+) > > diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h > index 7ff0ed4f292e..cc3f49415620 100644 > --- a/arch/riscv/include/asm/pgtable.h > +++ b/arch/riscv/include/asm/pgtable.h > @@ -404,6 +404,10 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma, > #define VMALLOC_END (PAGE_OFFSET - 1) > #define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE) > > +#define BPF_JIT_REGION_SIZE (SZ_128M) > +#define BPF_JIT_REGION_START (PAGE_OFFSET - BPF_JIT_REGION_SIZE) > +#define BPF_JIT_REGION_END (VMALLOC_END) > + Series looks good to me, thanks; I'd like to get an ACK from Palmer/others on this one. > /* > * Roughly size the vmemmap space to be large enough to fit enough > * struct pages to map half the virtual address space. Then > diff --git a/arch/riscv/net/bpf_jit_comp.c b/arch/riscv/net/bpf_jit_comp.c > index 8aa19c846881..46cff093f526 100644 > --- a/arch/riscv/net/bpf_jit_comp.c > +++ b/arch/riscv/net/bpf_jit_comp.c > @@ -1656,3 +1656,16 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) > tmp : orig_prog); > return prog; > } > + > +void *bpf_jit_alloc_exec(unsigned long size) > +{ > + return __vmalloc_node_range(size, PAGE_SIZE, BPF_JIT_REGION_START, > + BPF_JIT_REGION_END, GFP_KERNEL, > + PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE, > + __builtin_return_address(0)); > +} > + > +void bpf_jit_free_exec(void *addr) > +{ > + return vfree(addr); > +} >