From patchwork Mon Jan 18 17:27:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Henderson <1912065@bugs.launchpad.net> X-Patchwork-Id: 12027963 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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=ham 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 D000EC433E0 for ; Mon, 18 Jan 2021 17:57:16 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 CA57F22BEA for ; Mon, 18 Jan 2021 17:57:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CA57F22BEA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bugs.launchpad.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:60930 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l1YmB-0003ir-0E for qemu-devel@archiver.kernel.org; Mon, 18 Jan 2021 12:57:15 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:60590) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l1YRL-0001hb-SL for qemu-devel@nongnu.org; Mon, 18 Jan 2021 12:35:45 -0500 Received: from indium.canonical.com ([91.189.90.7]:59662) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1l1YRH-0006al-Nj for qemu-devel@nongnu.org; Mon, 18 Jan 2021 12:35:43 -0500 Received: from loganberry.canonical.com ([91.189.90.37]) by indium.canonical.com with esmtp (Exim 4.86_2 #2 (Debian)) id 1l1YRE-0006rt-Fl for ; Mon, 18 Jan 2021 17:35:36 +0000 Received: from loganberry.canonical.com (localhost [127.0.0.1]) by loganberry.canonical.com (Postfix) with ESMTP id 74BA52E813B for ; Mon, 18 Jan 2021 17:35:36 +0000 (UTC) MIME-Version: 1.0 Date: Mon, 18 Jan 2021 17:27:21 -0000 From: Richard Henderson <1912065@bugs.launchpad.net> To: qemu-devel@nongnu.org X-Launchpad-Notification-Type: bug X-Launchpad-Bug: product=qemu; status=In Progress; importance=Undecided; assignee=rth@twiddle.net; X-Launchpad-Bug-Information-Type: Public X-Launchpad-Bug-Private: no X-Launchpad-Bug-Security-Vulnerability: no X-Launchpad-Bug-Commenters: balaton-4 harrysintonen rth X-Launchpad-Bug-Reporter: Harry Sintonen (harrysintonen) X-Launchpad-Bug-Modifier: Richard Henderson (rth) References: <161081817733.30007.5357056175605529567.malonedeb@chaenomeles.canonical.com> Message-Id: <161099084144.30067.897245088295398204.malone@chaenomeles.canonical.com> Subject: [Bug 1912065] Re: Segfaults in tcg/optimize.c:212 after commit 7c79721606be11b5bc556449e5bcbc331ef6867d X-Launchpad-Message-Rationale: Subscriber (QEMU) @qemu-devel-ml X-Launchpad-Message-For: qemu-devel-ml Precedence: bulk X-Generated-By: Launchpad (canonical.com); Revision="511b4a3b6512aa3d421c5f7d74f3527e78bff26e"; Instance="production" X-Launchpad-Hash: a855cb50dd87c1f1b522a1eaac6e3fd4da793128 Received-SPF: none client-ip=91.189.90.7; envelope-from=bounces@canonical.com; helo=indium.canonical.com X-Spam_score_int: -65 X-Spam_score: -6.6 X-Spam_bar: ------ X-Spam_report: (-6.6 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.248, RCVD_IN_DNSWL_HI=-5, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Bug 1912065 <1912065@bugs.launchpad.net> Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The problem is that we're now generating many more temporaries than before, and running out of the statically allocated amount. Changing a debug assert to a full assert will change the SEGV into an ABRT. :-) But a proper solution is to dynamically allocate the temps. diff --git a/tcg/tcg.c b/tcg/tcg.c index 8f8badb61c..c376afe56a 100644 --- a/tcg/tcg.c +++ b/tcg/tcg.c @@ -1207,7 +1207,7 @@ void tcg_func_start(TCGContext *s) static inline TCGTemp *tcg_temp_alloc(TCGContext *s) { int n = s->nb_temps++; - tcg_debug_assert(n < TCG_MAX_TEMPS); + g_assert(n < TCG_MAX_TEMPS); return memset(&s->temps[n], 0, sizeof(TCGTemp)); } The problem can be worked around temporarily by increasing the number of temporaries: diff --git a/include/tcg/tcg.h b/include/tcg/tcg.h index 504c5e9bb0..8fe32bb03c 100644 --- a/include/tcg/tcg.h +++ b/include/tcg/tcg.h @@ -275,7 +275,7 @@ typedef struct TCGPool { #define TCG_POOL_CHUNK_SIZE 32768 -#define TCG_MAX_TEMPS 512 +#define TCG_MAX_TEMPS 2048 #define TCG_MAX_INSNS 512 /* when the size of the arguments of a called function is smaller than