From f24894771e384b1bc60dc0f2c104d7e7fad3c865 Mon Sep 17 00:00:00 2001 From: Andreas Arnez Date: Tue, 1 Mar 2016 12:43:55 +0100 Subject: [PATCH] S390: Fix internal error with stackless inferior This fixes a GDB internal error that may occur when the inferior has no valid stack pointer in r15. gdb/testsuite/ChangeLog: * gdb.arch/s390-stackless.S: New. * gdb.arch/s390-stackless.exp: New. gdb/ChangeLog: * s390-linux-tdep.c (s390_backchain_frame_unwind_cache): Avoid exception when attempting to access the inferior's backchain. --- gdb/ChangeLog | 5 +++ gdb/s390-linux-tdep.c | 6 ++-- gdb/testsuite/ChangeLog | 5 +++ gdb/testsuite/gdb.arch/s390-stackless.S | 33 +++++++++++++++++++ gdb/testsuite/gdb.arch/s390-stackless.exp | 39 +++++++++++++++++++++++ 5 files changed, 86 insertions(+), 2 deletions(-) create mode 100644 gdb/testsuite/gdb.arch/s390-stackless.S create mode 100644 gdb/testsuite/gdb.arch/s390-stackless.exp diff --git a/gdb/ChangeLog b/gdb/ChangeLog index a728959929..75c9285a78 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +2016-03-01 Andreas Arnez + + * s390-linux-tdep.c (s390_backchain_frame_unwind_cache): Avoid + exception when attempting to access the inferior's backchain. + 2016-02-29 Yao Qi * aarch64-linux-tdep.c (aarch64_canonicalize_syscall): Support diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c index 57e25b4317..7f860b60d6 100644 --- a/gdb/s390-linux-tdep.c +++ b/gdb/s390-linux-tdep.c @@ -2180,7 +2180,7 @@ s390_backchain_frame_unwind_cache (struct frame_info *this_frame, enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); CORE_ADDR backchain; ULONGEST reg; - LONGEST sp; + LONGEST sp, tmp; int i; /* Set up ABI call-saved/call-clobbered registers. */ @@ -2193,7 +2193,9 @@ s390_backchain_frame_unwind_cache (struct frame_info *this_frame, /* Get the backchain. */ reg = get_frame_register_unsigned (this_frame, S390_SP_REGNUM); - backchain = read_memory_unsigned_integer (reg, word_size, byte_order); + if (!safe_read_memory_integer (reg, word_size, byte_order, &tmp)) + tmp = 0; + backchain = (CORE_ADDR) tmp; /* A zero backchain terminates the frame chain. As additional sanity check, let's verify that the spill slot for SP in the diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 6aa071341c..84f963c54c 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2016-03-01 Andreas Arnez + + * gdb.arch/s390-stackless.S: New. + * gdb.arch/s390-stackless.exp: New. + 2016-02-28 Iain Buclaw * gdb.dlang/circular.c: New file. diff --git a/gdb/testsuite/gdb.arch/s390-stackless.S b/gdb/testsuite/gdb.arch/s390-stackless.S new file mode 100644 index 0000000000..77944ab64c --- /dev/null +++ b/gdb/testsuite/gdb.arch/s390-stackless.S @@ -0,0 +1,33 @@ +/* Copyright 2015-2016 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + + .text + + .align 8 + .globl main + .type main, @function + /* Ensure an invalid stack pointer and link register. Don't + use zero, since that may be handled specially. */ +main: la %r15,3(0,0) + la %r14,1(0,0) + j 1f + .size main, .-main + + /* Outside any function. */ + .byte 0,1 +1: st %r15,0(%r15) + br %r14 diff --git a/gdb/testsuite/gdb.arch/s390-stackless.exp b/gdb/testsuite/gdb.arch/s390-stackless.exp new file mode 100644 index 0000000000..b4aedb5568 --- /dev/null +++ b/gdb/testsuite/gdb.arch/s390-stackless.exp @@ -0,0 +1,39 @@ +# Copyright 2016 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program 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 General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +if {![istarget "s390*-*-*"]} then { + verbose "Skipping s390 stackless test." + return +} + +standard_testfile .S + +if { [prepare_for_testing $testfile.exp $testfile $srcfile] } { + return -1 +} + +# Run until SIGSEGV. +gdb_run_cmd + +set test "run until SIGSEGV" +gdb_test_multiple "" $test { + -re "Program received signal SIGSEGV.*$gdb_prompt $" { + pass $test + } +} + +# Ensure that 'info registers' works properly and does not generate +# an internal-error. +gdb_test "info registers" "r0.*" "info registers" -- 2.34.1