From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi1-x232.google.com (mail-oi1-x232.google.com [IPv6:2607:f8b0:4864:20::232]) by sourceware.org (Postfix) with ESMTPS id B257F3894C27; Thu, 22 Apr 2021 17:22:51 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org B257F3894C27 Received: by mail-oi1-x232.google.com with SMTP id k25so46545107oic.4; Thu, 22 Apr 2021 10:22:51 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=wiTnZ0jb8T8DIT/T8M7MZNloAR8N8bfDZKt8Mmfbp9g=; b=TVDj0+R9MHoOnGPNFWUC8mwW1CJIYwI/k/fE9RiaWFAg2sV/1PteBgQrW2n4K5FQSO 0hhHnwGiViy/r/mgg358Qi9vfde/npUQ2JTWQL+947HwdthuwuId1Ajg46uEq2So3lE3 9KPnsA+r36+PS0a23O2YfyZQDVH7IBgAVZsH0Rko/CxGseLCYD3ODgXiZsiiG2Y7rXuH 6Q01dJYOypnTQ/0IIj1Dfy7vYFp+n8SbvoP7lxECVCzcFw+0pEkus6lZ/eVAAGcozVCW uGki2IbDjTDG51RTve5B2SGN5qcVnMjcxCHvnC+vzYX1GLTAUILryXSHOzTNNS4UuM+Y W15g== X-Gm-Message-State: AOAM531aH0BAFgWTjkmiZZFuI/q/bT84SNXJQEdIYykbSXMkH1rdBoN4 lNwHLWR+hEYLBfr+CdgFiBDsutBfTcySRKCaSWaKcOn1rCs= X-Google-Smtp-Source: ABdhPJywA6RsSQC7OTpI/ukUMxvqS7LBA+6v3vZSwkVp/Ntxh21fQyAuB4O8rNB6hF5AU0YGxBkM69OH1Whg8xeqXjY= X-Received: by 2002:aca:b208:: with SMTP id b8mr749791oif.79.1619112171200; Thu, 22 Apr 2021 10:22:51 -0700 (PDT) MIME-Version: 1.0 References: <87tuo24kxi.fsf@oldenburg.str.redhat.com> <87czunoo5m.fsf@oldenburg.str.redhat.com> <20210422072821.GE9028@arm.com> <87o8e6k9br.fsf@oldenburg.str.redhat.com> <20210422090501.GH9028@arm.com> <20210422094808.GJ9028@arm.com> <87pmymildh.fsf@oldenburg.str.redhat.com> <20210422124455.GK9028@arm.com> <20210422142030.GL9028@arm.com> <87pmymgzuy.fsf@oldenburg.str.redhat.com> <20210422153008.GM9028@arm.com> In-Reply-To: <20210422153008.GM9028@arm.com> From: "H.J. Lu" Date: Thu, 22 Apr 2021 10:22:15 -0700 Message-ID: Subject: Re: [PATCH v3] nptl_db: Support different libpthread/ld.so load orders (bug 27744) To: Szabolcs Nagy Cc: Florian Weimer , Pedro Alves , Florian Weimer via Libc-alpha , GDB Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-3028.4 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 22 Apr 2021 17:23:02 -0000 On Thu, Apr 22, 2021 at 10:16 AM Szabolcs Nagy via Gdb-patches wrote: > > The 04/22/2021 16:25, Florian Weimer wrote: > > * Szabolcs Nagy: > > > > > if i rerun the link command of the test exe but with -no-pie > > > instead of -pie then the test passes with that binary. > > > > > > i suspect gdb places the breakpoint at the wrong place in pie > > > for some reason. can be ubuntu tooling specific. see the > > > breakpoint location (the exe base offset is missing): > > > > Thanks for investigating. > > > > > +attach 1254516 > > > [New LWP 1254517] > > > Trying host libthread_db library: /home/szabolcs/try/build/nptl_db/libthread_db.so.1. > > > td_ta_new failed: application not linked with libthread > > > thread_db_load_search returning 0 > > > Trying host libthread_db library: /home/szabolcs/try/build/nptl_db/libthread_db.so.1. > > > [Thread debugging using libthread_db enabled] > > > Using host libthread_db library "/home/szabolcs/try/build/nptl_db/libthread_db.so.1". > > > thread_db_load_search returning 1 > > > 0x0000ffff9d3d89c4 in __futex_abstimed_wait_common64 (futex_word=0xffff9d363210, expected=1254517, clockid=, abstime=0x0, private=, cancel=cancel@entry=true) at futex-internal.c:74 > > > 74 err = INTERNAL_SYSCALL_CANCEL (futex_time64, futex_word, op, expected, > > > +break debugger_inspection_point > > > Breakpoint 1 at 0x20c0: file tst-pthread-gdb-attach.c, line 123. > > > +continue > > > > Would you please check if the issue goes away if you replace > > > > "add-symbol-file %1$s/nptl/tst-pthread-gdb-attach\n" > > > > with > > "file %1$s/nptl/tst-pthread-gdb-attach\n" > > > > ? > > > > (I assume this happens without --enable-hardcoded-path-in-tests.) > > yes, it seems gdb does not work with > > ld.so ./exe > > if exe is pie. i could not get it to work wit file either. Just pass -no-pie to build exe. > add-symbol-file fails even without ld.so, just pie exe fails. > > you have to use -o offset argument to add-symbol-file and > manually fish out the base offset from info proc map, i don't > think that can be easily scripted. > -- H.J.