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 69CFEC001E0 for ; Tue, 25 Jul 2023 11:05:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233991AbjGYLFm (ORCPT ); Tue, 25 Jul 2023 07:05:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41328 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233914AbjGYLFX (ORCPT ); Tue, 25 Jul 2023 07:05:23 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C7B48211C for ; Tue, 25 Jul 2023 04:03:17 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6299F61654 for ; Tue, 25 Jul 2023 11:03:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 77352C433C8; Tue, 25 Jul 2023 11:03:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1690282996; bh=kXxw1DAJtq0QErLe+OIvVSnDPdsqzKuJbrqyl7OqZ7M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HJtfpyYIM79mA3Wb5v6SOeU3Qj70nulDorh9DS/o6kntvxiANPDcUlUQMVKhe2Res Pv7pe8TM7H8kuLMvJz4KTSMdhHYBeVs4P5yvDcCQ9hUwNEc4b6iNJcsaK+KDvXNopZ WNMJnf0UmBdED3C2TCspw/sADja93/mc+kfld+Os= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zhen Lei , Luis Chamberlain , Sasha Levin Subject: [PATCH 6.1 102/183] kallsyms: Correctly sequence symbols when CONFIG_LTO_CLANG=y Date: Tue, 25 Jul 2023 12:45:30 +0200 Message-ID: <20230725104511.616653083@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230725104507.756981058@linuxfoundation.org> References: <20230725104507.756981058@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Zhen Lei [ Upstream commit 010a0aad39fccceba4a07d30d163158a39c704f3 ] LLVM appends various suffixes for local functions and variables, suffixes observed: - foo.llvm.[0-9a-f]+ - foo.[0-9a-f]+ Therefore, when CONFIG_LTO_CLANG=y, kallsyms_lookup_name() needs to truncate the suffix of the symbol name before comparing the local function or variable name. Old implementation code: - if (strcmp(namebuf, name) == 0) - return kallsyms_sym_address(i); - if (cleanup_symbol_name(namebuf) && strcmp(namebuf, name) == 0) - return kallsyms_sym_address(i); The preceding process is traversed by address from low to high. That is, for those with the same name after the suffix is removed, the one with the smallest address is returned first. Therefore, when sorting in the tool, if the raw names are the same, they should be sorted by address in ascending order. ASCII[.] = 2e ASCII[0-9] = 30,39 ASCII[A-Z] = 41,5a ASCII[_] = 5f ASCII[a-z] = 61,7a According to the preceding ASCII code values, the following sorting result is strictly followed. --------------------------------- | main-key | sub-key | |---------------------------------| | | addr_lowest | | | ... | | . | ... | | | addr_highest | |---------------------------------| | ? | | //? is [_A-Za-z0-9] --------------------------------- Signed-off-by: Zhen Lei Signed-off-by: Luis Chamberlain Stable-dep-of: 8cc32a9bbf29 ("kallsyms: strip LTO-only suffixes from promoted global functions") Signed-off-by: Sasha Levin --- scripts/kallsyms.c | 36 ++++++++++++++++++++++++++++++++++-- scripts/link-vmlinux.sh | 4 ++++ 2 files changed, 38 insertions(+), 2 deletions(-) diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index dcb744a067e5e..67ef9aa14a770 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -78,6 +78,7 @@ static unsigned int table_size, table_cnt; static int all_symbols; static int absolute_percpu; static int base_relative; +static int lto_clang; static int token_profit[0x10000]; @@ -89,7 +90,7 @@ static unsigned char best_table_len[256]; static void usage(void) { fprintf(stderr, "Usage: kallsyms [--all-symbols] [--absolute-percpu] " - "[--base-relative] in.map > out.S\n"); + "[--base-relative] [--lto-clang] in.map > out.S\n"); exit(1); } @@ -411,6 +412,34 @@ static int symbol_absolute(const struct sym_entry *s) return s->percpu_absolute; } +static char * s_name(char *buf) +{ + /* Skip the symbol type */ + return buf + 1; +} + +static void cleanup_symbol_name(char *s) +{ + char *p; + + if (!lto_clang) + return; + + /* + * ASCII[.] = 2e + * ASCII[0-9] = 30,39 + * ASCII[A-Z] = 41,5a + * ASCII[_] = 5f + * ASCII[a-z] = 61,7a + * + * As above, replacing '.' with '\0' does not affect the main sorting, + * but it helps us with subsorting. + */ + p = strchr(s, '.'); + if (p) + *p = '\0'; +} + static int compare_names(const void *a, const void *b) { int ret; @@ -421,7 +450,9 @@ static int compare_names(const void *a, const void *b) expand_symbol(sa->sym, sa->len, sa_namebuf); expand_symbol(sb->sym, sb->len, sb_namebuf); - ret = strcmp(&sa_namebuf[1], &sb_namebuf[1]); + cleanup_symbol_name(s_name(sa_namebuf)); + cleanup_symbol_name(s_name(sb_namebuf)); + ret = strcmp(s_name(sa_namebuf), s_name(sb_namebuf)); if (!ret) { if (sa->addr > sb->addr) return 1; @@ -855,6 +886,7 @@ int main(int argc, char **argv) {"all-symbols", no_argument, &all_symbols, 1}, {"absolute-percpu", no_argument, &absolute_percpu, 1}, {"base-relative", no_argument, &base_relative, 1}, + {"lto-clang", no_argument, <o_clang, 1}, {}, }; diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 918470d768e9c..32e573943cf03 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -156,6 +156,10 @@ kallsyms() kallsymopt="${kallsymopt} --base-relative" fi + if is_enabled CONFIG_LTO_CLANG; then + kallsymopt="${kallsymopt} --lto-clang" + fi + info KSYMS ${2} scripts/kallsyms ${kallsymopt} ${1} > ${2} } -- 2.39.2