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 D975CC38145 for ; Fri, 2 Sep 2022 14:33:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236717AbiIBOd0 (ORCPT ); Fri, 2 Sep 2022 10:33:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37148 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236217AbiIBOaX (ORCPT ); Fri, 2 Sep 2022 10:30:23 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AABDD20F4B for ; Fri, 2 Sep 2022 06:54:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=Mk4gyPud12Euk/9XIHAPXis5fefrr9FnQg5Sg88vnL0=; b=X7Th3/a7wdt17ojxWrABzi5Ae8 oaJGENC29iMmbnDD3sh8vciSWHTDv2S3CaixkPjaGmC8OFjWx8NmpOqDVD0tbLjtH12mbRFODkxng PQo1KpOw1+NUHQnIopLOq87lu91khcWU0khwjLFicn4aOgFEtgBlxPbOp4uBsrXdnYLS39sfc+8dS OtT7nzeilsw5T/nJ2Ip42YCzEUjMrYtHimjs0zmUx0pgSsVeMP/JHZQpxjuwxSa9uMNQ1ZyGwiYVK lsebNDTOjDbP7PMGbrg1grISQc38zNKmCNsaCIvRRlR0HUz85NIXbBtvAaGEMXJEmS8wyE3fE6Qe5 nwaLhoXQ==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1oU77P-008g8l-Jq; Fri, 02 Sep 2022 13:54:03 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 451CC302DA9; Fri, 2 Sep 2022 15:53:54 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id A654D2B8EFB60; Fri, 2 Sep 2022 15:53:53 +0200 (CEST) Message-ID: <20220902130951.853460809@infradead.org> User-Agent: quilt/0.66 Date: Fri, 02 Sep 2022 15:07:18 +0200 From: Peter Zijlstra To: Thomas Gleixner Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, x86@kernel.org, Linus Torvalds , Tim Chen , Josh Poimboeuf , Andrew Cooper , Pawan Gupta , Johannes Wikner , Alyssa Milburn , Jann Horn , "H.J. Lu" , Joao Moreira , Joseph Nuzman , Steven Rostedt , Juergen Gross , Masami Hiramatsu , Alexei Starovoitov , Daniel Borkmann , K Prateek Nayak , Eric Dumazet Subject: [PATCH v2 53/59] kallsyms: Take callthunks into account References: <20220902130625.217071627@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Peter Zijlstra Since the pre-symbol function padding is an integral part of the symbol make kallsyms report it as part of the symbol by reporting it as sym-x instead of prev_sym+y. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) --- kernel/kallsyms.c | 45 ++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 40 insertions(+), 5 deletions(-) --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -292,6 +292,12 @@ static unsigned long get_symbol_pos(unsi return low; } +#ifdef CONFIG_FUNCTION_PADDING_BYTES +#define PADDING_BYTES CONFIG_FUNCTION_PADDING_BYTES +#else +#define PADDING_BYTES 0 +#endif + /* * Lookup an address but don't bother to find any names. */ @@ -299,13 +305,25 @@ int kallsyms_lookup_size_offset(unsigned unsigned long *offset) { char namebuf[KSYM_NAME_LEN]; + int ret; + + addr += PADDING_BYTES; if (is_ksym_addr(addr)) { get_symbol_pos(addr, symbolsize, offset); - return 1; + ret = 1; + goto found; } - return !!module_address_lookup(addr, symbolsize, offset, NULL, NULL, namebuf) || - !!__bpf_address_lookup(addr, symbolsize, offset, namebuf); + + ret = !!module_address_lookup(addr, symbolsize, offset, NULL, NULL, namebuf); + if (!ret) { + ret = !!__bpf_address_lookup(addr, symbolsize, + offset, namebuf); + } +found: + if (ret && offset) + *offset -= PADDING_BYTES; + return ret; } static const char *kallsyms_lookup_buildid(unsigned long addr, @@ -318,6 +336,8 @@ static const char *kallsyms_lookup_build namebuf[KSYM_NAME_LEN - 1] = 0; namebuf[0] = 0; + addr += PADDING_BYTES; + if (is_ksym_addr(addr)) { unsigned long pos; @@ -347,6 +367,8 @@ static const char *kallsyms_lookup_build found: cleanup_symbol_name(namebuf); + if (ret && offset) + *offset -= PADDING_BYTES; return ret; } @@ -373,6 +395,8 @@ int lookup_symbol_name(unsigned long add symname[0] = '\0'; symname[KSYM_NAME_LEN - 1] = '\0'; + addr += PADDING_BYTES; + if (is_ksym_addr(addr)) { unsigned long pos; @@ -400,6 +424,8 @@ int lookup_symbol_attrs(unsigned long ad name[0] = '\0'; name[KSYM_NAME_LEN - 1] = '\0'; + addr += PADDING_BYTES; + if (is_ksym_addr(addr)) { unsigned long pos; @@ -416,6 +442,8 @@ int lookup_symbol_attrs(unsigned long ad return res; found: + if (offset) + *offset -= PADDING_BYTES; cleanup_symbol_name(name); return 0; } @@ -441,8 +469,15 @@ static int __sprint_symbol(char *buffer, len = strlen(buffer); offset -= symbol_offset; - if (add_offset) - len += sprintf(buffer + len, "+%#lx/%#lx", offset, size); + if (add_offset) { + char s = '+'; + + if ((long)offset < 0) { + s = '-'; + offset = 0UL - offset; + } + len += sprintf(buffer + len, "%c%#lx/%#lx", s, offset, size); + } if (modname) { len += sprintf(buffer + len, " [%s", modname);