From patchwork Mon Feb 17 13:59:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 183577 Delivered-To: patch@linaro.org Received: by 2002:a92:1f12:0:0:0:0:0 with SMTP id i18csp4970831ile; Mon, 17 Feb 2020 06:00:04 -0800 (PST) X-Google-Smtp-Source: APXvYqxQbBwVJY8RbUQPPYEEo4VVyYdjfnwFeonQIp7dv/oLluXwA1zHLSSZD3rMmIoLU8cWdqQK X-Received: by 2002:aca:100e:: with SMTP id 14mr10097630oiq.88.1581948004706; Mon, 17 Feb 2020 06:00:04 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1581948004; cv=none; d=google.com; s=arc-20160816; b=dM+L5SBi20A0/x6bJKHx0lnt5MLjby7aaTlne0TVY++1x/3TnYDzsgBIXIDSp04Wh4 OCyUfQSbcY0Xg+zvrM212LNmpd7+SgU73gQRcm3rxQ4ag3DBeHrPZDpAOxezYtFL2TYK GnZJea2wQw959arBykFjhStx3dhdFi/ggF/JF9cG0/TNHH6JPTUvvT/W8P0qaSqEv0TW EDEd2ztO26ouHi7lKdjJDjbrkQL0K1byqu/dhWJK1yTP4kZep6e8ZUHM2vzsVGdL7bH4 TniU/l2BeJaW6i1HYNI3Dz1ERaKiCWfw74fY0poU2ZxdqpWICuPU62fTRMRtfPSIWLli wgVQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=message-id:date:subject:to:from:dkim-signature:delivered-to:sender :list-help:list-post:list-archive:list-subscribe:list-unsubscribe :list-id:precedence:mailing-list:dkim-signature:domainkey-signature; bh=aVFNYgH7JlhGirsD47xot7Vagw5CIxmVmItRyp/Z9GA=; b=0SlHSASJUEy78PeBjfCoZ8i1ATLrOj5DUHG0Cotqj+QtOFu+torIjTMcF0uwzDb0aF WMlgYqkjwoohfFtbE4R1BYkecH42hHIjDgDIjBBnLjXn80+z6fBBsD+2bB8FQC8ObI5C BY5wkJQb/yXQoJhsIu9jTGqYwEK7WplrUDmEaS/MwCFCLl7Npxoc0JsVqAnRiExVk8tN OCMJURrHKRT8NOqa2i/kEt2fWSi5VCeKPBMNi4RkBGeCWiwtJfUTH7zJVCI1uW1G7S16 q2+TQaV56xo3Cjs3YDHzbCXcdUYxsSk74ZMKELSaKBebPShSX7zFm/PmkP8JaIlJr3hs NAkA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@sourceware.org header.s=default header.b=d5C7W1yp; dkim=pass header.i=@linaro.org header.s=google header.b=i9GFwaed; spf=pass (google.com: domain of libc-alpha-return-109855-patch=linaro.org@sourceware.org designates 209.132.180.131 as permitted sender) smtp.mailfrom="libc-alpha-return-109855-patch=linaro.org@sourceware.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Return-Path: Received: from sourceware.org (server1.sourceware.org. [209.132.180.131]) by mx.google.com with ESMTPS id n11si217249otq.112.2020.02.17.06.00.04 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 17 Feb 2020 06:00:04 -0800 (PST) Received-SPF: pass (google.com: domain of libc-alpha-return-109855-patch=linaro.org@sourceware.org designates 209.132.180.131 as permitted sender) client-ip=209.132.180.131; Authentication-Results: mx.google.com; dkim=pass header.i=@sourceware.org header.s=default header.b=d5C7W1yp; dkim=pass header.i=@linaro.org header.s=google header.b=i9GFwaed; spf=pass (google.com: domain of libc-alpha-return-109855-patch=linaro.org@sourceware.org designates 209.132.180.131 as permitted sender) smtp.mailfrom="libc-alpha-return-109855-patch=linaro.org@sourceware.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:subject:date:message-id; q=dns; s= default; b=DPrdZPQJcMubUr1qtMkzIBHkWp6v75rgbjLpoDDAuRIbZ3/0vFk2H ZG5df2X5QrKKix67TuhY9f+woBvbUSBd8xKM0nvSaNDZtCLBjUNbXNnMOLlW5fPB qDX4DFHGO51sQgrl9xjIa3QyQUTBbg2YJzlZ2rGsWWJu/oTflcyILQ= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:subject:date:message-id; s=default; bh=/6YVwAR34hUIb74jROTtV5hwZns=; b=d5C7W1ypyPtTrOLI3AT/QIMPKLfJ 3R2D/LHbqaCv35P55tPphqTwt1c7h5gJKV7gJffLe0chpPRIEBLLFHUqIGg2pYNk dteW0VkvCbm8hThpwgvY7GMFy1GTy6rDilZHs/ONMiLetMpBsLVJaC5+Z18nFaTI gfxpbxJQZbQt3Fo= Received: (qmail 47492 invoked by alias); 17 Feb 2020 13:59:55 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 47464 invoked by uid 89); 17 Feb 2020 13:59:54 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-22.0 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_PASS autolearn=ham version=3.3.1 spammy= X-HELO: mail-qk1-f195.google.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:subject:date:message-id; bh=aVFNYgH7JlhGirsD47xot7Vagw5CIxmVmItRyp/Z9GA=; b=i9GFwaedg41CC0FcnLY6nJhE+nbnXRgAbXv0HS365iJ7Rhx4ybwBfTCmJfroO9i4is ZvwfdmpwtxH8mpiv/6eo0EJWr2IZRB2eq7/MqkN6ZullY5uKCFt46+blMdGKf8tKsRUL r0meRoeOFDY2b0AFhL5p4GsHKtKB7GKIj/mxWcKxP1jeR1VYO/Op7Vl+ZfA2QFupeuW9 a004ra0+TKmh9bOO52/BtEzl2UDqJ2beeR9No3oo+E/GN5YCOtzmLY1PBLjMz2g7RW/u 5IDcFUixrvC8sVZp2uPLNqoXoLN3V4svDNtzS1iIH1dO3pUfoGdNuRNobkpyB9qyneqK Azjw== Return-Path: From: Adhemerval Zanella To: libc-alpha@sourceware.org Subject: [PATCH] mips: Fix bracktrace result for signal frames Date: Mon, 17 Feb 2020 10:59:44 -0300 Message-Id: <20200217135944.4688-1-adhemerval.zanella@linaro.org> MIPS fallback code handle a frame where its FDE can not be obtained (for instance a signal frame) by reading the kernel allocated signal frame and adding '2' to the value of 'sc_pc' [1]. The added value is used to recognize an end of an EH region on mips16 [2]. The fix adjust the obtained signal frame value and remove the libgcc added value by checking if the previous frame is a signal frame one. Checked with backtrace and tst-sigcontext-get_pc tests on mips-linux-gnu and mips64-linux-gnu. [1] libgcc/config/mips/linux-unwind.h from gcc code. [2] gcc/config/mips/mips.h from gcc code. */ --- debug/backtrace.c | 5 ++ sysdeps/generic/unwind-arch.h | 30 ++++++++++ sysdeps/unix/sysv/linux/mips/unwind-arch.h | 67 ++++++++++++++++++++++ 3 files changed, 102 insertions(+) create mode 100644 sysdeps/generic/unwind-arch.h create mode 100644 sysdeps/unix/sysv/linux/mips/unwind-arch.h -- 2.17.1 diff --git a/debug/backtrace.c b/debug/backtrace.c index cc4b9a5c90..69cf4c23c8 100644 --- a/debug/backtrace.c +++ b/debug/backtrace.c @@ -23,6 +23,7 @@ #include #include #include +#include struct trace_arg { @@ -78,6 +79,10 @@ backtrace_helper (struct _Unwind_Context *ctx, void *a) if (arg->cnt != -1) { arg->array[arg->cnt] = (void *) unwind_getip (ctx); + if (arg->cnt > 0) + arg->array[arg->cnt] + = unwind_arch_adjustment (arg->array[arg->cnt - 1], + arg->array[arg->cnt]); /* Check whether we make any progress. */ _Unwind_Word cfa = unwind_getcfa (ctx); diff --git a/sysdeps/generic/unwind-arch.h b/sysdeps/generic/unwind-arch.h new file mode 100644 index 0000000000..d712e5e11d --- /dev/null +++ b/sysdeps/generic/unwind-arch.h @@ -0,0 +1,30 @@ +/* Return backtrace of current program state. Arch-specific bits. + Copyright (C) 2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _UNWIND_ARCH_H +#define _UNWIND_ARCH_H + +#include + +static inline void * +unwind_arch_adjustment (void *prev, void *addr) +{ + return addr; +} + +#endif diff --git a/sysdeps/unix/sysv/linux/mips/unwind-arch.h b/sysdeps/unix/sysv/linux/mips/unwind-arch.h new file mode 100644 index 0000000000..a009899983 --- /dev/null +++ b/sysdeps/unix/sysv/linux/mips/unwind-arch.h @@ -0,0 +1,67 @@ +/* Return backtrace of current program state. Arch-specific bits. + Copyright (C) 2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _UNWIND_ARCH_H +#define _UNWIND_ARCH_H + +#include + +/* MIPS fallback code handle a frame where its FDE can not be obtained + (for instance a signal frame) by reading the kernel allocated signal frame + and adding '2' to the value of 'sc_pc' [1]. The added value is used to + recognize an end of an EH region on mips16 [2]. + + The idea here is to adjust the obtained signal frame ADDR value and remove + the libgcc added value by checking if the previous frame is a signal frame + one. + + [1] libgcc/config/mips/linux-unwind.h from gcc code. + [2] gcc/config/mips/mips.h from gcc code. */ + +static inline void * +unwind_arch_adjustment (void *prev, void *addr) +{ + uint32_t *pc = (uint32_t *) prev; + + if (pc == NULL) + return addr; + + /* For MIPS16 or microMIPS frame libgcc makes no adjustment. */ + if ((uintptr_t) pc & 0x3) + return addr; + + /* The vDSO containes either + + 24021061 li v0, 0x1061 (rt_sigreturn) + 0000000c syscall + or + 24021017 li v0, 0x1017 (sigreturn) + 0000000c syscall */ + if (pc[1] != 0x0000000c) + return addr; +#if _MIPS_SIM == _ABIO32 + if (pc[0] == (0x24020000 | __NR_sigreturn)) + return (void *) ((uintptr_t) addr - 2); +#endif + if (pc[0] == (0x24020000 | __NR_rt_sigreturn)) + return (void *) ((uintptr_t) addr - 2); + + return addr; +} + +#endif