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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1033AC43334 for ; Mon, 18 Jul 2022 15:37:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235597AbiGRPhO (ORCPT ); Mon, 18 Jul 2022 11:37:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49684 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234134AbiGRPhM (ORCPT ); Mon, 18 Jul 2022 11:37:12 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4CBADBC81; Mon, 18 Jul 2022 08:37:10 -0700 (PDT) Received: from kwepemi500013.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4LmmHt66YzzlW4M; Mon, 18 Jul 2022 23:35:22 +0800 (CST) Received: from [10.67.111.192] (10.67.111.192) by kwepemi500013.china.huawei.com (7.221.188.120) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 18 Jul 2022 23:37:02 +0800 Message-ID: Date: Mon, 18 Jul 2022 23:37:01 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.9.0 Subject: Re: [PATCH bpf-next v9 3/4] bpf, arm64: Implement bpf_arch_text_poke() for arm64 Content-Language: en-US To: Jon Hunter , , , , , Jean-Philippe Brucker , Will Deacon , KP Singh CC: Mark Rutland , Catalin Marinas , Daniel Borkmann , Alexei Starovoitov , Andrii Nakryiko , Zi Shen Lim , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , "David S . Miller" , Hideaki YOSHIFUJI , David Ahern , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , , "H . Peter Anvin" , Jakub Kicinski , Jesper Dangaard Brouer , Russell King , James Morse , Hou Tao , Jason Wang References: <20220711150823.2128542-1-xukuohai@huawei.com> <20220711150823.2128542-4-xukuohai@huawei.com> <8de014c1-aa63-5783-e5fd-53b7fdece805@nvidia.com> From: Xu Kuohai In-Reply-To: <8de014c1-aa63-5783-e5fd-53b7fdece805@nvidia.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.111.192] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To kwepemi500013.china.huawei.com (7.221.188.120) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/18/2022 9:52 PM, Jon Hunter wrote: [..] > > This change appears to be causing the build to fail ... > > /tmp/cc52xO0c.s: Assembler messages: > /tmp/cc52xO0c.s:8: Error: operand 1 should be an integer register -- > `mov lr,x9' > /tmp/cc52xO0c.s:7: Error: undefined symbol lr used as an immediate value > make[2]: *** [scripts/Makefile.build:250: arch/arm64/net/bpf_jit_comp.o] > Error 1 > make[1]: *** [scripts/Makefile.build:525: arch/arm64/net] Error 2 > > Let me know if you have any thoughts. > Sorry for this failure, but I can't reproduce it. I guess maybe your assembler doesn't recognize "lr". Could you give a try to replace "lr" with "x30"? #if IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) " bti j\n" /* dummy_tramp is called via "br x10" */ #endif -" mov x10, lr\n" -" mov lr, x9\n" +" mov x10, x30\n" +" mov x30, x9\n" " ret x10\n" " .size dummy_tramp, .-dummy_tramp\n" " .popsection\n Thanks. > Cheers > Jon >