From patchwork Mon Oct 2 16:57:47 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 13406480 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 1E133E748F8 for ; Mon, 2 Oct 2023 16:58:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238069AbjJBQ6D (ORCPT ); Mon, 2 Oct 2023 12:58:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51384 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238530AbjJBQ6C (ORCPT ); Mon, 2 Oct 2023 12:58:02 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4CBA9B3; Mon, 2 Oct 2023 09:58:00 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 05865C433CC; Mon, 2 Oct 2023 16:57:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1696265880; bh=y6877j2bTNQK/NlDbP64SUFTPt4nOaXWX04vbP+P73g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Hmy8ZejQMQr9mppLprDw2FZUxnXL+GWtTdfc5nxI8WF7LrtdYXmB8aPOcC1PYcs9n EI4Kg0gqqHVkF+v1KN2+CEtMfxb/+iWB19vFi1NDZONKB461wxPKUHdKSeQDoOYxLS /KA7mrChpNt2Rvi1LPGfKgTjMSMPnmtiWvJMNQekpdf2ayWMbE0Tc5ncFh4vqLZU6K +s62izIU3+M4JJKZXJRlWVoTnUYQW3V1vChjWCN38WSUF0vbUgJlRh0nGTBs7BDVV9 DsR+fqXIef71qsHr2IXBy031ChUI51Wl3o3Wqo/dFO4mR9pIpTCWFgTao2uiv6b2Vi KPRTgl6Ye96Ww== From: Will Deacon To: linux-kernel@vger.kernel.org Cc: kernel-team@android.com, Will Deacon , Masahiro Yamada , Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Josh Poimboeuf , John Stultz , linux-kbuild@vger.kernel.org Subject: [PATCH v5 1/3] scripts/faddr2line: Don't filter out non-function symbols from readelf Date: Mon, 2 Oct 2023 17:57:47 +0100 Message-Id: <20231002165750.1661-2-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20231002165750.1661-1-will@kernel.org> References: <20231002165750.1661-1-will@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org As Josh points out in 20230724234734.zy67gm674vl3p3wv@treble: > Problem is, I think the kernel's symbol printing code prints the > nearest kallsyms symbol, and there are some valid non-FUNC code > symbols. For example, syscall_return_via_sysret. so we shouldn't be considering only 'FUNC'-type symbols in the output from readelf. Drop the function symbol type filtering from the faddr2line outer loop. Cc: John Stultz Suggested-by: Josh Poimboeuf Reviewed-by: Nick Desaulniers Link: https://lore.kernel.org/r/20230724234734.zy67gm674vl3p3wv@treble Signed-off-by: Will Deacon --- scripts/faddr2line | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/faddr2line b/scripts/faddr2line index 0e73aca4f908..a35a420d0f26 100755 --- a/scripts/faddr2line +++ b/scripts/faddr2line @@ -260,7 +260,7 @@ __faddr2line() { DONE=1 - done < <(${READELF} --symbols --wide $objfile | sed 's/\[.*\]//' | ${AWK} -v fn=$sym_name '$4 == "FUNC" && $8 == fn') + done < <(${READELF} --symbols --wide $objfile | sed 's/\[.*\]//' | ${AWK} -v fn=$sym_name '$8 == fn') } [[ $# -lt 2 ]] && usage From patchwork Mon Oct 2 16:57:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 13406481 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 3AA8CE748FC for ; Mon, 2 Oct 2023 16:58:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238530AbjJBQ6H (ORCPT ); Mon, 2 Oct 2023 12:58:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51446 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238546AbjJBQ6G (ORCPT ); Mon, 2 Oct 2023 12:58:06 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C0264B8; Mon, 2 Oct 2023 09:58:02 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6CEE9C433C7; Mon, 2 Oct 2023 16:58:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1696265882; bh=q5YCA8p0CGC7cTGNfTdRfhSsu0Oi56m79bI+z6AlhIY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=smS5zvrQR+zwmmjSJOrtQGBHEGCoK9wYqujaWmDDRGeHNtGeUZ5yPgbZGMXTK2u+x AW8tODwGP5hVzlD0/G6LuTLfzTslF9o5X2rhAtCDzLOxadA0j66DBebRXWUi1sbp+9 TdNm6VV3MivgjNXLYi2V84DAQ0hVShAmQWPUjodVam4s7JTCbMBhPKV73ml/++V3uN jwAvEyLfyzujWkMNOrIRG/MzGBudnLWmnHCjOu0cWcfdKuyOZwsnUSwt7wBCwKrjCG mXABdfgP2hAdr52MbifgZup1jO4ZM6unX39omk5yuoYov7cKTzppRQoOPcTIZOJdzA pG3ghlndlW0wQ== From: Will Deacon To: linux-kernel@vger.kernel.org Cc: kernel-team@android.com, Will Deacon , Masahiro Yamada , Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Josh Poimboeuf , John Stultz , linux-kbuild@vger.kernel.org Subject: [PATCH v5 2/3] scripts/faddr2line: Use LLVM addr2line and readelf if LLVM=1 Date: Mon, 2 Oct 2023 17:57:48 +0100 Message-Id: <20231002165750.1661-3-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20231002165750.1661-1-will@kernel.org> References: <20231002165750.1661-1-will@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org GNU utilities cannot necessarily parse objects built by LLVM, which can result in confusing errors when using 'faddr2line': $ CROSS_COMPILE=aarch64-linux-gnu- ./scripts/faddr2line vmlinux do_one_initcall+0xf4/0x260 aarch64-linux-gnu-addr2line: vmlinux: unknown type [0x13] section `.relr.dyn' aarch64-linux-gnu-addr2line: DWARF error: invalid or unhandled FORM value: 0x25 do_one_initcall+0xf4/0x260: aarch64-linux-gnu-addr2line: vmlinux: unknown type [0x13] section `.relr.dyn' aarch64-linux-gnu-addr2line: DWARF error: invalid or unhandled FORM value: 0x25 $x.73 at main.c:? Although this can be worked around by setting CROSS_COMPILE to "llvm=-", it's cleaner to follow the same syntax as the top-level Makefile and accept LLVM= as an indication to use the llvm- tools, optionally specifying their location or specific version number. Cc: Josh Poimboeuf Cc: John Stultz Suggested-by: Masahiro Yamada Signed-off-by: Will Deacon Reviewed-by: Nick Desaulniers --- scripts/faddr2line | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/scripts/faddr2line b/scripts/faddr2line index a35a420d0f26..6b8206802157 100755 --- a/scripts/faddr2line +++ b/scripts/faddr2line @@ -58,8 +58,21 @@ die() { exit 1 } -READELF="${CROSS_COMPILE:-}readelf" -ADDR2LINE="${CROSS_COMPILE:-}addr2line" +UTIL_SUFFIX="" +if [[ "${LLVM:-}" == "" ]]; then + UTIL_PREFIX=${CROSS_COMPILE:-} +else + UTIL_PREFIX=llvm- + + if [[ "${LLVM}" == *"/" ]]; then + UTIL_PREFIX=${LLVM}${UTIL_PREFIX} + elif [[ "${LLVM}" == "-"* ]]; then + UTIL_SUFFIX=${LLVM} + fi +fi + +READELF="${UTIL_PREFIX}readelf${UTIL_SUFFIX}" +ADDR2LINE="${UTIL_PREFIX}addr2line${UTIL_SUFFIX}" AWK="awk" GREP="grep" From patchwork Mon Oct 2 16:57:49 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 13406482 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 2733CE784AB for ; Mon, 2 Oct 2023 16:58:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238568AbjJBQ6O (ORCPT ); Mon, 2 Oct 2023 12:58:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59866 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238546AbjJBQ6I (ORCPT ); Mon, 2 Oct 2023 12:58:08 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 23D00B4; Mon, 2 Oct 2023 09:58:05 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D177DC433CA; Mon, 2 Oct 2023 16:58:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1696265884; bh=BdsyPvEj53bRhSrPGLPqhoMZxFh5sEybiAwaA9VVpew=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MoarQNNeg90+ZrJS/8bCWOtdeyip/Ehjh86/RE+EGGzvFDosBwZcGY1z1RQ63OveD SMdtoHLgk61DoaWo1+DjXCqTATkbwX0SsEhgSEop0Ngos/5ZZ3DSfm26vZYJQ6Iqju EJxZisKAzbqHVcj5x2mQ8JsErjOOdCMg4KYsdU5/iD5ER243gBlawhplsUzfDDPEMf kAPfyNyPNRUJ2Dhx9r0HAXeSGtgjlTcj/gPVFyoSlPWvAJbmF6ah3ivJ7MUt+mcjKV eElZNnBThoDIIihUby56Wwn1BWy4wASAaMOEUXf+OoOUtzAUib5VMG++5Wc/IuTEhc T7d7sF6HltmXA== From: Will Deacon To: linux-kernel@vger.kernel.org Cc: kernel-team@android.com, Will Deacon , Masahiro Yamada , Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Josh Poimboeuf , John Stultz , linux-kbuild@vger.kernel.org Subject: [PATCH v5 3/3] scripts/faddr2line: Skip over mapping symbols in output from readelf Date: Mon, 2 Oct 2023 17:57:49 +0100 Message-Id: <20231002165750.1661-4-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20231002165750.1661-1-will@kernel.org> References: <20231002165750.1661-1-will@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Mapping symbols emitted in the readelf output can confuse the 'faddr2line' symbol size calculation, resulting in the erroneous rejection of valid offsets. This is especially prevalent when building an arm64 kernel with CONFIG_CFI_CLANG=y, where most functions are prefixed with a 32-bit data value in a '$d.n' section. For example: 447538: ffff800080014b80 548 FUNC GLOBAL DEFAULT 2 do_one_initcall 104: ffff800080014c74 0 NOTYPE LOCAL DEFAULT 2 $x.73 106: ffff800080014d30 0 NOTYPE LOCAL DEFAULT 2 $x.75 111: ffff800080014da4 0 NOTYPE LOCAL DEFAULT 2 $d.78 112: ffff800080014da8 0 NOTYPE LOCAL DEFAULT 2 $x.79 36: ffff800080014de0 200 FUNC LOCAL DEFAULT 2 run_init_process Adding a warning to do_one_initcall() results in: | WARNING: CPU: 0 PID: 1 at init/main.c:1236 do_one_initcall+0xf4/0x260 Which 'faddr2line' refuses to accept: $ ./scripts/faddr2line vmlinux do_one_initcall+0xf4/0x260 skipping do_one_initcall address at 0xffff800080014c74 due to size mismatch (0x260 != 0x224) no match for do_one_initcall+0xf4/0x260 Filter out these entries from readelf using a shell reimplementation of is_mapping_symbol(), so that the size of a symbol is calculated as a delta to the next symbol present in ksymtab. Cc: Josh Poimboeuf Cc: John Stultz Suggested-by: Masahiro Yamada Signed-off-by: Will Deacon Reviewed-by: Nick Desaulniers Reviewed-by: Masahiro Yamada --- scripts/faddr2line | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/scripts/faddr2line b/scripts/faddr2line index 6b8206802157..587415a52b6f 100755 --- a/scripts/faddr2line +++ b/scripts/faddr2line @@ -179,6 +179,11 @@ __faddr2line() { local cur_sym_elf_size=${fields[2]} local cur_sym_name=${fields[7]:-} + # is_mapping_symbol(cur_sym_name) + if [[ ${cur_sym_name} =~ ^(\.L|L0|\$) ]]; then + continue + fi + if [[ $cur_sym_addr = $sym_addr ]] && [[ $cur_sym_elf_size = $sym_elf_size ]] && [[ $cur_sym_name = $sym_name ]]; then