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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DDE9FC53219 for ; Mon, 27 Jul 2026 07:48:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ZStcuhfdE7XxAahWW2ecan0c6zEbfCVD7CPTonvHjSo=; b=HFl7zji5TowpgTX5VhHNb0CFXE 0vn+Uq/sRJw1fI//l2JAOKkrMe59ZJxrSafBfK4kMpOq8kDRYXLh7dGh5xzjXJHlboXHpXS5XiMvg E9/ghE7GfTQss2/ak21k2dRpcrOPWJaf4XUFbtkDEpiNPKHnYHBPLNxRwH8OKMaex13ht6FNTNqhS d8e/bVlGJQCZpSXZNpquCfDln1TTuh8szmUrr8ng/Qz1FAuNhsNaUMmliN2xHd7SG2jU1EUzbhHnU qrZ7Xy24FEsJ4xFQmyM8YFgw5OJ/n0RrFDHB7I1uiSMqxvsASlf1pzBjOeb0IGEtTstHlTXzunvwC PxRT1WGQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1woG4A-00000002BHR-3SeI; Mon, 27 Jul 2026 07:48:02 +0000 Received: from m16.mail.163.com ([117.135.210.5]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1woG48-00000002BGr-2IYO for linux-arm-kernel@lists.infradead.org; Mon, 27 Jul 2026 07:48:02 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=ZS tcuhfdE7XxAahWW2ecan0c6zEbfCVD7CPTonvHjSo=; b=CBkWPhc1I89BZjYVgz 2ISa/fi0husOK1ZC2jKDPaF2RFEHOebY9qtFwtzHf7y/lM2AmLMIbkwnEJFcqIA6 318vwueZQwqLNa2xArFLKj/qz/EMjp/1zteiJgY7VP37trSOeZBwc7uxWLSnn6ZD /ajRq0ym5l46ubQLp7lN4FmrU= Received: from fedora (unknown []) by gzsmtp3 (Coremail) with SMTP id PigvCgA3UdQJDWdq26SaJw--.39752S2; Mon, 27 Jul 2026 15:47:21 +0800 (CST) From: Ju Nan To: egg12138@foxmail.com Cc: jpoimboe@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-modules@vger.kernel.org, linux@armlinux.org.uk, pmladek@suse.com, Ju Nan Subject: Re: [PATCH v3] ARM: module.lds: fix unwind metadata for merged .text sections Date: Mon, 27 Jul 2026 15:47:09 +0800 Message-ID: <20260727074708.115112-2-junan76@163.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID: PigvCgA3UdQJDWdq26SaJw--.39752S2 X-Coremail-Antispam: 1Uf129KBjvdXoWrZF48uFyrZFyDGFWDArW7CFg_yoWDurgEg3 Wvq34Utw17W34Duws8Ar4YyFyDWr4UWF17Jay8AFZIyr40qrsIvw1rAr90vF17Xa1xurZ3 ua43XrZ8uwn7tjkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7VUUxR65UUUUU== X-Originating-IP: [2409:8a62:3e6:69d0:2c5f:9e47:5815:6758] X-CM-SenderInfo: pmxqt0ixw6il2tof0z/xtbC0wm5a2pnDQkD8wAA3x X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260727_004801_038897_E3DDC9F2 X-CRM114-Status: UNSURE ( 6.18 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org I ran into exactly the same on a STM32MP157A-DK1 board (dual Cortex-A7, ARMv7 AEABI, CONFIG_ARM_UNWIND=y). An out-of-tree module whose functions GCC had placed in .text.unlikely (merged into .text by module.lds.S) left its .ARM.exidx.text.unlikely section unregistered, so an Oops inside the module produced an empty backtrace: Call trace: unwind: Index not found bf102018 With this patch applied, the module's exidx is coalesced into a single .ARM.exidx output section, module_finalize() registers it against .text, and the full module backtrace is restored: Call trace: do_the_crash [oops_null] from level_one+0x8/0xc [oops_null] level_one [oops_null] from level_two+0x8/0xc [oops_null] level_two [oops_null] from trigger_write+0x18/0x20 [oops_null] trigger_write [oops_null] from full_proxy_write+0x54/0x78 full_proxy_write from vfs_write+0xd0/0x49c vfs_write from ksys_write+0x6c/0xf4 ksys_write from ret_fast_syscall+0x0/0x54 Tested on Linux 7.1.4 Tested-by: Ju Nan