From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt1-x844.google.com (mail-qt1-x844.google.com [IPv6:2607:f8b0:4864:20::844]) by sourceware.org (Postfix) with ESMTPS id B43303858D1E for ; Wed, 29 Mar 2023 12:42:21 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org B43303858D1E Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-qt1-x844.google.com with SMTP id s12so11327413qtx.11 for ; Wed, 29 Mar 2023 05:42:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1680093741; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=jMxVaHXKvXdPeauAnuhpowYtWy1elJcjeFDFSQ9kXFk=; b=BD9fOTkI/9adw5ddPNE4Ybw19tqH+1sjmVQbXD27en7OervQpfUnLl8Tg4jaxORKRt Lb4kWFO8424pSpFPzah734Zj6Y2i/RCKulm+rQxR5Wb0xs+LQaNrs3MIzG2Clb2Q6/jt HniesdEjJZvlhrO4tlKKKRlRAxeovUnGxqE03IEAdIlt5AQ7lb/B3rDXqSdMwLJAdjAy dag+fpgYJqOICG96nTk92vumzHwbrA+DP0pQSJM//guFjx1KEajEbgkRY+Jd6mvHccm9 P3oJTs+nTnmBikNR76r2m/8ejRvGrSC08upTMGQSU1vWOhQ7z9zOCZy30dKdtnMV4/Sl uWTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1680093741; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=jMxVaHXKvXdPeauAnuhpowYtWy1elJcjeFDFSQ9kXFk=; b=n9gM0kc0KrGzULJh+1pYWHgecL3Mc7Ty00JtXWemRqhmFnr/MCVNyneC+vPFQszOei FseDqWPaeOJ3WDPnjuCv8BBTPZ76dApau5xQwJi3sBkjJHMGD41ohZxCvnzdWVvSnsEv fWXJufn/+1e3aUc891SX1Ac6nq3AjDb9upbMdhgcXzhhELzYBd4tEVW5QNGK5VO4/E3+ vQWo2h5dEyMFKDVx69ulPGmFuQZoIso6YW+0+FMDZ8pDi0NENkJfx19RLCyEw96qdAf3 MUK5lLl+SUaBGRYnzFPjTPTsqt3V/BiZBQX9l2EOSyOVXvhTmMtAi+bkd/AHwfpBBjYK LYSw== X-Gm-Message-State: AO0yUKWb7zpV3/DAHRlE5nyibeVX0x8rGSpA5HdabR7zCBQkllpa7rtf fcSxp49gDEVnA/8Yn8f/KlEV6xxPMqo+tiSEN5E= X-Google-Smtp-Source: AK7set9FEhCQzESg1vzJK16xXg/a6CQonxbw+aKJu/XvS6B+1f0zDkb8L/8kKMFPl2httZR1a+O1vV+LjFKF1WinT3s= X-Received: by 2002:ac8:7f87:0:b0:3e1:2295:9ec1 with SMTP id z7-20020ac87f87000000b003e122959ec1mr7086993qtj.7.1680093741060; Wed, 29 Mar 2023 05:42:21 -0700 (PDT) MIME-Version: 1.0 References: <20230319205529.75469-1-dmytro.medvied@gmail.com> In-Reply-To: From: =?UTF-8?B?0JTQvNC40YLRgNC+INCc0LXQtNCy0ZTQtNGM?= Date: Wed, 29 Mar 2023 15:42:09 +0300 Message-ID: Subject: Re: [PATCH] aarch64: Fix an infinite loop on bt when the core dump has an SVE section but the target does not support it. To: Luis Machado Cc: gdb-patches@sourceware.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-0.7 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=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: Hi Luis, On Mon, Mar 27, 2023 at 12:43=E2=80=AFPM Luis Machado wrote: > Hi, > > That's interesting. If the target doesn't support SVE, why is the SVE_MAG= IC context being generated in the first place? > > It should've been handled by the default case, where we increment the sec= tion by the size. > > If gdb knows about SVE, it should be able to handle it, unless the target= says the vector length is 0. > > Could you please clarify what target you observed this on? The core dump was generated on the Amazon EC2 instance that is powered by Arm-based AWS Graviton3 processor. It was not generated by gdb. To make the core dump a modification of a third party tool https://github.com/Percona-Lab/coredumper was used. I assume that this coredumper does not write all the info that is needed for gdb to resolve the SVE section correctly. I will prepare a minimal working example which reproduces the issue with modified Percona-Lab coredumper and will provide the source and the core dump, but I still think that infinite loop should be fixed in gdb as well and maybe a warning should be added in this case.