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 5D5F7CCA473 for ; Wed, 15 Jun 2022 20:50:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346681AbiFOUur (ORCPT ); Wed, 15 Jun 2022 16:50:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45212 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345229AbiFOUup (ORCPT ); Wed, 15 Jun 2022 16:50:45 -0400 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 6076054FB8; Wed, 15 Jun 2022 13:50:44 -0700 (PDT) Received: from [192.168.254.32] (unknown [47.189.24.195]) by linux.microsoft.com (Postfix) with ESMTPSA id 4EBE220C3239; Wed, 15 Jun 2022 13:50:43 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 4EBE220C3239 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1655326244; bh=g9704SjoKYmdPNDdsnilrDNVoFNTzb9pQq5FDWCboIk=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=CdpzSuhYdpPjRSdBKuc4tFQ2xeCwmjUl5arBWWMfq7WF6Dbrb/ZuupbR+7A7RrSu1 3w16/w8IReQMB2GF7bl5KZg4sgfw4FpHFQxovdKDtdpQXrhSxc3drB4yxVaSbT/NbJ SzWgEfKyR/m8b+BAmY3xBw7XgHUv5oI/zv+RozRY= Message-ID: <0f673713-ce37-1328-59da-2d623a6627e9@linux.microsoft.com> Date: Wed, 15 Jun 2022 15:50:42 -0500 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [RFC PATCH v2 00/20] arm64: livepatch: Use ORC for dynamic frame pointer validation Content-Language: en-US To: Mark Rutland , "Ivan T. Ivanov" Cc: jpoimboe@redhat.com, peterz@infradead.org, chenzhongjin@huawei.com, broonie@kernel.org, nobuta.keiya@fujitsu.com, sjitindarsingh@gmail.com, catalin.marinas@arm.com, will@kernel.org, jamorris@linux.microsoft.com, linux-arm-kernel@lists.infradead.org, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org References: <20220524001637.1707472-1-madvenka@linux.microsoft.com> <20220615121844.34v7cos5kcz2hufk@suse> From: "Madhavan T. Venkataraman" In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/15/22 08:37, Mark Rutland wrote: > On Wed, Jun 15, 2022 at 03:18:44PM +0300, Ivan T. Ivanov wrote: >> I have run following [1] livepatch tests on kernel build from your repository. >> Overall results looks good, but when I run klp_tc_13.shI there is something which >> I still can not understand completely. It is because of kaslr. >> >> [ 36.817617] livepatch: enabling patch 'klp_tc_13_livepatch' >> [ 36.819602] branch_imm_common: offset out of range >> [ 36.820113] branch_imm_common: offset out of range >> [ 36.820643] ------------[ ftrace bug ]------------ >> [ 36.821172] ftrace failed to modify >> [ 36.821173] [] orig_do_read_active_livepatch_id+0x4/0xa8 [klp_test_support_mod] >> [ 36.822465] actual: e4:01:00:94 >> [ 36.822821] Updating ftrace call site to call a different ftrace function >> [ 36.823537] ftrace record flags: e4000002 >> [ 36.823953] (2) R >> [ 36.823953] expected tramp: ffffdde96882e224 >> [ 36.824619] ------------[ cut here ]------------ >> [ 36.825125] WARNING: CPU: 0 PID: 950 at kernel/trace/ftrace.c:2085 ftrace_bug+0x98/0x280 >> [ 36.826027] Modules linked in: klp_tc_13_livepatch(OK+) klp_test_support_mod(O) crct10dif_ce >> [ 36.826943] CPU: 0 PID: 950 Comm: insmod Tainted: G O K 5.18.0-rc1-00020-g1ffee6fdcfda #39 >> [ 36.827987] Hardware name: linux,dummy-virt (DT) >> [ 36.828546] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) >> [ 36.829348] pc : ftrace_bug+0x98/0x280 >> [ 36.829790] lr : ftrace_bug+0x228/0x280 >> [ 36.830224] sp : ffff8000084038e0 >> [ 36.830620] x29: ffff8000084038e0 x28: ffff00000485a920 x27: ffffdde931176804 >> [ 36.831419] x26: ffffdde93117d1a0 x25: ffff00000485a900 x24: ffffdde96aea1000 >> [ 36.832226] x23: 0000000000000000 x22: 0000000000000001 x21: ffffdde96a124da0 >> [ 36.833024] x20: ffff0000045620f0 x19: ffffdde96b54a358 x18: ffffffffffffffff >> [ 36.833818] x17: 5b20386178302f34 x16: 78302b64695f6863 x15: ffffdde96a3078f8 >> [ 36.834621] x14: 0000000000000000 x13: 3432326532383836 x12: ffffdde96ae9b3d8 >> [ 36.835425] x11: 0000000000000001 x10: 0000000000000001 x9 : ffffdde96891305c >> [ 36.836221] x8 : c0000000ffffefff x7 : 0000000000017fe8 x6 : ffffdde96ae83398 >> [ 36.837023] x5 : 0000000000057fa8 x4 : 0000000000000000 x3 : 00000000ffffefff >> [ 36.837836] x2 : e32439832ffb9700 x1 : 0000000000000000 x0 : 0000000000000022 >> [ 36.838635] Call trace: >> [ 36.838923] ftrace_bug+0x98/0x280 >> [ 36.839319] ftrace_replace_code+0xa0/0xb8 >> [ 36.839768] ftrace_modify_all_code+0xc0/0x160 >> [ 36.840273] arch_ftrace_update_code+0x14/0x20 >> [ 36.840780] ftrace_run_update_code+0x24/0x78 >> [ 36.841283] ftrace_startup_enable+0x50/0x60 >> [ 36.841781] ftrace_startup+0xb4/0x178 >> [ 36.842214] register_ftrace_function+0x68/0x88 >> [ 36.842738] klp_patch_object+0x1c8/0x330 >> [ 36.843196] klp_enable_patch+0x468/0x828 > > IIUC that splat specifically is due to ftrace_modify_call() missing module PLT lookups. > > That should be fixed by: > > https://lore.kernel.org/all/20220614080944.1349146-3-mark.rutland@arm.com/ > > I have not looked at the rest of this series (yet). > > Thanks, > Mark. Thank you so much, Mark! I will include this in my patch series until it is upstream. Madhavan