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 X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 496ABC48BE5 for ; Tue, 15 Jun 2021 06:02:34 +0000 (UTC) Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D587061403 for ; Tue, 15 Jun 2021 06:02:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D587061403 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=vt.edu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernelnewbies-bounces@kernelnewbies.org Received: from localhost ([::1] helo=shelob.surriel.com) by shelob.surriel.com with esmtp (Exim 4.94.2) (envelope-from ) id 1lt29A-0001ZB-Fl; Tue, 15 Jun 2021 02:02:00 -0400 Received: from mail-qk1-x72c.google.com ([2607:f8b0:4864:20::72c]) by shelob.surriel.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94.2) (envelope-from ) id 1lt295-0001X7-EZ for kernelnewbies@kernelnewbies.org; Tue, 15 Jun 2021 02:01:55 -0400 Received: by mail-qk1-x72c.google.com with SMTP id c5so3706033qka.4 for ; Mon, 14 Jun 2021 23:01:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=vt-edu.20150623.gappssmtp.com; s=20150623; h=sender:from:to:cc:subject:in-reply-to:references:mime-version :content-transfer-encoding:date:message-id; bh=hU6KF1QteRzp94WHWeDMHaD6sdkSsGnJbuIcBbeeKRM=; b=xaIMflzrsbdNiflG5ipYz91p/qR3J7U5Of34nmQovAM3+401MO0JSITcfp+AH9UYH0 26IM9NTJJbMB2vyrYva7+Ek6ypsnG6RaKAvYvrblK2rM7Ee7X9bQu5pTCpgPFqYSfLxa MYC/Nr8El/pz0CR+v5WaTXa4xiDGgXaVazg1N2u/IgYIuPEUYQQ7G3wZ4W0wkQFtQhJY Yuxm06ARJOgHmj5fO+rtr0Nl8/Km8/2nGNtQohcfDlCA+USVfC4j8enbdHGEL2YPnbVo rSVaQBqmOfKcrIAyxAcIDOeWrvijI5uH7pBVvuLD+djEx7a5twBSXCWNDGfUhQXG7Rpw +xsw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:in-reply-to:references :mime-version:content-transfer-encoding:date:message-id; bh=hU6KF1QteRzp94WHWeDMHaD6sdkSsGnJbuIcBbeeKRM=; b=ogR82kdlveRIGmKolRSbq6RzsQmcaeWuCAJb3b7OaUVnUemK3WWsa5CjQEGjP16srE /oPwFgGiHURJXC9uwjTt4hqdsAdgVdWUZQ39mezuJ9wMGpDw0L78z2RLU3i7eQeq00K3 1bj5tbdkZcw/8uZWZxK3/zW19iBthXC7Tn1ecgWEisnpI2gdhZKMir1yOf3v15l1LosM cQbjdRipbBcc2Qb6HmnyTks53+T0XyJfZR7IkQWzV+G48AXlr61/po5cpphUUMDuUduX lPkJLoltjw6IIUSgZD5bEtWyHWiM2wHtKeSwMXcfJ2mncRUSAmYwUS2WhmxgN+knnuAF Iwig== X-Gm-Message-State: AOAM531Bnn040RbBVjGE3aKGY++YBQLxIHEmeiIYZnR7xbIBRyxu3/4D nBucO9OxkPBlBKokjAnO4ZERIQ== X-Google-Smtp-Source: ABdhPJyS22VsI1T5BLiWbkuNNxiVf2gqYjodW7DgRQXxzxbMkYMOHo7zCjvO4C+7l1umeNVEgm+CSQ== X-Received: by 2002:a37:278f:: with SMTP id n137mr19855621qkn.154.1623736912823; Mon, 14 Jun 2021 23:01:52 -0700 (PDT) Received: from turing-police ([2601:5c0:c380:d61::359]) by smtp.gmail.com with ESMTPSA id f2sm4176047qtk.54.2021.06.14.23.01.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 14 Jun 2021 23:01:52 -0700 (PDT) From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Google-Original-From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Mailer: exmh version 2.9.0 11/07/2018 with nmh-1.7+dev To: hemanth nandish Subject: Re: Getting backtrace of a process In-Reply-To: References: Mime-Version: 1.0 Date: Tue, 15 Jun 2021 02:01:51 -0400 Message-ID: <27375.1623736911@turing-police> Cc: kernelnewbies@kernelnewbies.org X-BeenThere: kernelnewbies@kernelnewbies.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Learn about the Linux kernel List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============7771115741611117848==" Errors-To: kernelnewbies-bounces@kernelnewbies.org --===============7771115741611117848== Content-Type: multipart/signed; boundary="==_Exmh_1623736911_27061P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit --==_Exmh_1623736911_27061P Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On Mon, 14 Jun 2021 20:40:57 +0530, hemanth nandish said: > As per my understanding, the *do_coredump* kills the faulty process ins= ide > *coredump_wait* function before invoking the userspace handler, > This might be the reason the libunwind fails to gather the backtrace as= it > uses PTRACE calls. > > Is there any way to overcome this without modifying the kernel code? You might want to look at how gdb implements stuff like 'thread apply all= bt', which works just fine on a coredump. --==_Exmh_1623736911_27061P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Comment: Exmh version 2.9.0 11/07/2018 iQIVAwUBYMhCTgdmEQWDXROgAQKtpBAAvyTTJ+EYrCd0EA2+bQfc8UUo74YfGZRz /td+9+G6K/ozJl+muXsSXbpyH1kDOswTYhUkAL3iEzWc+oVd+ByIszzv7R5N2iKb IVx2lU1srJ7vsfJLbIiULRpwPQ+o5d9Iu/Tmwkz7l5ywamSKZHYDCl20n5vHdn1d zsqZ1h+0tfGQ+gbB9+s6zb5CkGzEe09wrd4iNQzQeSO9LMr/JW3/1MdLkLwwd0Gy jFui25gSg9hZWdQlvKORWND6OBiMp3jXtVqMrxLRPVLxH2Mh9u0iBMnmCGW5+PWb 9GPiY9M5xrQtJbu/g7lzTsA4hMq7MfepxnUwSiGv2w5ep8/8SKxik+tSvfMKiC5p tihoa6t3pgVEPFfaDkudZaR0BWXBCZ0gw+DPXXW/lLRdBjqVaGNne8ZlGpuiQ5CW fN24goT8glDq7sp7PLyewawXN5n+9CAQcIE62aa9ji/jDo+RG2j1DSot5Kj82ekL fIANlH+xu2EpVSRfQ83zPWuXPBKbqQrrBJxTdI50AsbulDfXjOH5w0GEkmFVmDm4 q4bL1JAi7OFLoXnQorFkTfSy0SIeTJA5HiI0SxOEQYeW/3E9/Lp5WycwJaJbxXK0 RhYe4w/o7ja8i3HFF9m18oIrvxV7DCJL8JwnHFW6GLMC+21TEO9b+l3BcQxKUcjy alMGq77dYpA= =8tiT -----END PGP SIGNATURE----- --==_Exmh_1623736911_27061P-- --===============7771115741611117848== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies --===============7771115741611117848==--