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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 31A09C43381 for ; Mon, 18 Feb 2019 05:32:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0287D218D8 for ; Mon, 18 Feb 2019 05:32:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727643AbfBRFb7 (ORCPT ); Mon, 18 Feb 2019 00:31:59 -0500 Received: from szxga06-in.huawei.com ([45.249.212.32]:47898 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725730AbfBRFb6 (ORCPT ); Mon, 18 Feb 2019 00:31:58 -0500 Received: from DGGEMS413-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 8E1CE8CD8F587F0E1B95; Mon, 18 Feb 2019 13:31:56 +0800 (CST) Received: from [127.0.0.1] (10.184.38.59) by DGGEMS413-HUB.china.huawei.com (10.3.19.213) with Microsoft SMTP Server id 14.3.408.0; Mon, 18 Feb 2019 13:31:48 +0800 Subject: Re: [PATCH] x86: livepatch: Treat R_X86_64_PLT32 as R_X86_64_PC32 To: Jiri Kosina , "chenzefeng (A)" CC: "hjl.tools@gmail.com" , "jpoimboe@redhat.com" , "sjenning@redhat.com" , "vojtech@suse.com" , "tglx@linutronix.de" , "mingo@redhat.com" , "hpa@zytor.com" , "gregkh@linuxfoundation.org" , "x86@kernel.org" , "live-patching@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "Xiexiuqi (Xie XiuQi)" References: <79A62BFA453EFB42B7A4E40AD8F3A2264F2A872D@DGGEMA503-MBX.china.huawei.com> From: "chengjian (D)" Message-ID: Date: Mon, 18 Feb 2019 13:29:11 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="gbk"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.184.38.59] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org HiŁ¬Jiri This patch should be merged into 4.4 stable, which still use klp_write_module_reloc. https://elixir.bootlin.com/linux/v4.4.174/source/arch/x86/kernel/livepatch.c ZeFeng may have sent a stable(4.4-y) patch to the wrong mail-list(mainline). Thanks. On 2019/2/15 15:28, Jiri Kosina wrote: > On Fri, 15 Feb 2019, chenzefeng (A) wrote: > >> On x86-64, for 32-bit PC-relacive branches, we can generate PLT32 >> relocation, instead of PC32 relocation. and R_X86_64_PLT32 can be >> treated the same as R_X86_64_PC32 since linux kernel doesn't use PLT. >> >> In linux 4.4 commit b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as >> R_X86_64_PC32") been fixed for the module loading, but not fixed for >> livepatch relocation, which will fail to load livepatch with the error >> message as follow: relocation failed for symbol at > address> >> >> Signed-off-by: chenzefeng > What kernel version is this patch based on? We've got rid of x86-specific > module loading stub and offloaded all the relocation handling to generic > kmod loader long time ago. >