From patchwork Tue Oct 15 11:39:10 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tiezhu Yang X-Patchwork-Id: 13836244 Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 118071E6321; Tue, 15 Oct 2024 11:39:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=114.242.206.163 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728992363; cv=none; b=Y3TWjeDHprUJVaHXp8RIHjIfr4Czx1Pv3X6ivAYmkZV1+wWOjHgI6bxEfE06K/2IuGsxDXlWjpSLRC0Ws1cF+yaxodnYnNeq/wj0SfvcTXdLJtebm5Luou0R+DZVX8aEgCX1V2CSO5Efdqc2eES0zrrgSyhHW3mae8Wxz/qJBT0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728992363; c=relaxed/simple; bh=+QVfX6uapABdVeCjMpgWmzX0OQSpPJMdLuTtOhOojko=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nd77opW9tQspoz3qKFz6dn4rq/BgRBagLlgeiC9IjQ+6xSi2KjF1KAojHLzzkYAuuBa0ctJa+KcdK446ETAZBmbg8g/U46C83ETRNwxkOh7j01nD+f1D9xR9rl+AWyrKuuA5/6BpTpMuq+lr2FcR1HN1u3K/SuHHx6Hnz0VXUnA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn; spf=pass smtp.mailfrom=loongson.cn; arc=none smtp.client-ip=114.242.206.163 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=loongson.cn Received: from loongson.cn (unknown [113.200.148.30]) by gateway (Coremail) with SMTP id _____8Cx44hmVA5n6X8dAA--.42655S3; Tue, 15 Oct 2024 19:39:18 +0800 (CST) Received: from linux.localdomain (unknown [113.200.148.30]) by front2 (Coremail) with SMTP id qciowMCxbcdkVA5n6E0uAA--.9583S3; Tue, 15 Oct 2024 19:39:17 +0800 (CST) From: Tiezhu Yang To: Huacai Chen , Josh Poimboeuf , Peter Zijlstra Cc: loongarch@lists.linux.dev, bpf@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v1 1/6] objtool: Check various symbol types for jump table Date: Tue, 15 Oct 2024 19:39:10 +0800 Message-ID: <20241015113915.12623-2-yangtiezhu@loongson.cn> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20241015113915.12623-1-yangtiezhu@loongson.cn> References: <20241015113915.12623-1-yangtiezhu@loongson.cn> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: qciowMCxbcdkVA5n6E0uAA--.9583S3 X-CM-SenderInfo: p1dqw3xlh2x3gn0dqz5rrqw2lrqou0/ X-Coremail-Antispam: 1Uk129KBj93XoWxJFWDKF4kAF4kGrW3Aw4xGrX_yoW5GFykpF sxG345Kr4Yqr1xWwnrtFZY9Fy3Gws7WFnrJrZrKr4Fv3sFvr1rKFWakw1ay3WDGr1Svw47 XF4Ygry7uF4UA3gCm3ZEXasCq-sJn29KB7ZKAUJUUUUr529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUU9Yb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r1Y6r17M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_JFI_Gr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AK xVW8Jr0_Cr1UM2kKe7AKxVWUXVWUAwAS0I0E0xvYzxvE52x082IY62kv0487Mc804VCY07 AIYIkI8VC2zVCFFI0UMc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWU AVWUtwAv7VC2z280aVAFwI0_Gr0_Cr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7V AKI48JMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMxCIbckI1I0E14v2 6r1Y6r17MI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17 CEb7AF67AKxVWUAVWUtwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1I6r4UMIIF 0xvE2Ix0cI8IcVCY1x0267AKxVWUJVW8JwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIx AIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVWUJVW8JbIYCTnIWIev Ja73UjIFyTuYvjxU466zUUUUU In the relocation section ".rela.rodata" of each .o file compiled with LoongArch toolchain, there are various symbol types such as STT_NOTYPE, STT_OBJECT, STT_FUNC in addition to the usual STT_SECTION, it needs to use reloc symbol offset instead of reloc addend to find the destination instruction in find_jump_table() and add_jump_table(). This is preparation for later patch on LoongArch, there is no effect for the other archs with this patch. Signed-off-by: Tiezhu Yang --- tools/objtool/check.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 6604f5d038aa..cda7306d07c2 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -2079,6 +2079,7 @@ static int add_jump_table(struct objtool_file *file, struct instruction *insn, unsigned int prev_offset = 0; struct reloc *reloc = table; struct alternative *alt; + unsigned long offset; /* * Each @reloc is a switch table relocation which points to the target @@ -2094,12 +2095,16 @@ static int add_jump_table(struct objtool_file *file, struct instruction *insn, if (prev_offset && reloc_offset(reloc) != prev_offset + 8) break; + if (reloc->sym->type == STT_SECTION) + offset = reloc_addend(reloc); + else + offset = reloc->sym->offset; + /* Detect function pointers from contiguous objects: */ - if (reloc->sym->sec == pfunc->sec && - reloc_addend(reloc) == pfunc->offset) + if (reloc->sym->sec == pfunc->sec && offset == pfunc->offset) break; - dest_insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc)); + dest_insn = find_insn(file, reloc->sym->sec, offset); if (!dest_insn) break; @@ -2137,6 +2142,7 @@ static struct reloc *find_jump_table(struct objtool_file *file, { struct reloc *table_reloc; struct instruction *dest_insn, *orig_insn = insn; + unsigned long offset; /* * Backward search using the @first_jump_src links, these help avoid @@ -2160,7 +2166,13 @@ static struct reloc *find_jump_table(struct objtool_file *file, table_reloc = arch_find_switch_table(file, insn); if (!table_reloc) continue; - dest_insn = find_insn(file, table_reloc->sym->sec, reloc_addend(table_reloc)); + + if (table_reloc->sym->type == STT_SECTION) + offset = reloc_addend(table_reloc); + else + offset = table_reloc->sym->offset; + + dest_insn = find_insn(file, table_reloc->sym->sec, offset); if (!dest_insn || !insn_func(dest_insn) || insn_func(dest_insn)->pfunc != func) continue;