From patchwork Fri Dec 31 15:10:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hou Tao X-Patchwork-Id: 12701963 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8094C433F5 for ; Fri, 31 Dec 2021 14:55:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230413AbhLaOzG (ORCPT ); Fri, 31 Dec 2021 09:55:06 -0500 Received: from szxga08-in.huawei.com ([45.249.212.255]:31064 "EHLO szxga08-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229474AbhLaOzF (ORCPT ); Fri, 31 Dec 2021 09:55:05 -0500 Received: from dggpeml500025.china.huawei.com (unknown [172.30.72.57]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4JQSlL3TmQz1DK4p; Fri, 31 Dec 2021 22:51:42 +0800 (CST) Received: from huawei.com (10.175.124.27) by dggpeml500025.china.huawei.com (7.185.36.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Fri, 31 Dec 2021 22:55:02 +0800 From: Hou Tao To: Alexei Starovoitov CC: Martin KaFai Lau , Yonghong Song , Daniel Borkmann , Andrii Nakryiko , Zi Shen Lim , Will Deacon , , , , Subject: [PATCH] bpf, arm64: use emit_addr_mov_i64() for BPF_PSEUDO_FUNC Date: Fri, 31 Dec 2021 23:10:18 +0800 Message-ID: <20211231151018.3781550-1-houtao1@huawei.com> X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 X-Originating-IP: [10.175.124.27] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpeml500025.china.huawei.com (7.185.36.35) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net The following error is reported when running "./test_progs -t for_each" under arm64: bpf_jit: multi-func JIT bug 58 != 56 ...... JIT doesn't support bpf-to-bpf calls The root cause is the size of BPF_PSEUDO_FUNC instruction increases from 2 to 3 after the address of called bpf-function is settled and there are two bpf-to-bpf calls in test_pkt_access. The generated instructions are shown below: >before callback_fn is jited, its addr is 0x1-00000001 0x48: 21 00 C0 D2 movz x1, #0x1, lsl #32 0x4c: 21 00 80 F2 movk x1, #0x1 >after callback_fn is jited, its addr is 0xfffffe0017f2fb84 0x48: E1 3F C0 92 movn x1, #0x1ff, lsl #32 0x4c: 41 FE A2 F2 movk x1, #0x17f2, lsl #16 0x50: 81 70 9F F2 movk x1, #0xfb84 Fixing it by using emit_addr_mov_i64() for BPF_PSEUDO_FUNC, so the size of jited image will not change. Fixes: 69c087ba6225 ("bpf: Add bpf_for_each_map_elem() helper") Signed-off-by: Hou Tao --- arch/arm64/net/bpf_jit_comp.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index f81e71f6e8bf..acfc3d4d712c 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -792,7 +792,10 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, u64 imm64; imm64 = (u64)insn1.imm << 32 | (u32)imm; - emit_a64_mov_i64(dst, imm64, ctx); + if (bpf_pseudo_func(insn)) + emit_addr_mov_i64(dst, imm64, ctx); + else + emit_a64_mov_i64(dst, imm64, ctx); return 1; }