From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id qQgUBaKmlWD3TgAAWB0awg (envelope-from ) for ; Fri, 07 May 2021 16:44:18 -0400 Received: by simark.ca (Postfix, from userid 112) id 04E531F11C; Fri, 7 May 2021 16:44:18 -0400 (EDT) X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on simark.ca X-Spam-Level: X-Spam-Status: No, score=-1.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPS id 5BB011E783 for ; Fri, 7 May 2021 16:44:17 -0400 (EDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 3B4A33894C24; Fri, 7 May 2021 20:44:16 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 3B4A33894C24 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1620420256; bh=OAwYnJwgOm3La4282p/HKuKghP6hfoQI9iNza3mAR1E=; h=To:Subject:References:Date:In-Reply-To:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=d4YqIhxstMEiy+fmss2VGGP79uBDNtQj3M8gF5lM2hTTXUSBIHzUuABJoeu2AP85p cJglHVS1E/AcfP39e1SuxNoQYInko3RM6CM+JB2nZvTictG7PEVWL1S3/UH3QbETWd izxYQOfVjmTwIMtlr9a22XbbumrtZJvmDLSKM6kY= Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by sourceware.org (Postfix) with ESMTP id AA2C83894C24 for ; Fri, 7 May 2021 20:44:11 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org AA2C83894C24 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-491-glBmuqYcOwqaKWu1dcKCIw-1; Fri, 07 May 2021 16:44:08 -0400 X-MC-Unique: glBmuqYcOwqaKWu1dcKCIw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 766B480575A; Fri, 7 May 2021 20:43:57 +0000 (UTC) Received: from oldenburg.str.redhat.com (ovpn-112-137.ams2.redhat.com [10.36.112.137]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3A4555D6AB; Fri, 7 May 2021 20:43:55 +0000 (UTC) To: Luis Machado via Libc-alpha Subject: Re: GDB shared library tracking with stap probes x _dl_debug_state References: Date: Fri, 07 May 2021 22:44:16 +0200 In-Reply-To: (Luis Machado via Libc-alpha's message of "Fri, 7 May 2021 16:42:03 -0300") Message-ID: <878s4qb7fj.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-BeenThere: gdb@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Florian Weimer via Gdb Reply-To: Florian Weimer Cc: "gdb@sourceware.org" , doko@debian.org Errors-To: gdb-bounces@sourceware.org Sender: "Gdb" * Luis Machado via Libc-alpha: > That's all fine, but there is one small detail that doesn't work for > armhf, and that is discovering if we're dealing with a PC that is arm > mode or thumb mode. Is it possible to recognize Arm mode vs thumb mode based on the NOP encoding at the probe address? > 2 - Not stripping ld.so/glibc. I can't determine the impact of this > choice, but distros strip binaries for a reason. Having to carry all > symbols for a particular library may not be desirable. We are switching Fedora to not strip ld.so, primarily for introspection purposes in Systemtap. (In Fedora, we've preserved the symbol table for ages, to make valgrind work.) Thanks, Florian