From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by sourceware.org (Postfix) with ESMTPS id 4075B385B832 for ; Mon, 23 Mar 2020 19:16:56 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 4075B385B832 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=tdevries@suse.de X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 4F1EFAA7C; Mon, 23 Mar 2020 19:16:55 +0000 (UTC) Subject: [PING^2][PATCH][gdb] Fix hang after ext sigkill From: Tom de Vries To: gdb-patches@sourceware.org Cc: Pedro Alves References: <20200224201403.GA7079@delia> <2dc5460f-33b3-227d-6e46-8d8663149931@suse.de> Autocrypt: addr=tdevries@suse.de; keydata= xsBNBF0ltCcBCADDhsUnMMdEXiHFfqJdXeRvgqSEUxLCy/pHek88ALuFnPTICTwkf4g7uSR7 HvOFUoUyu8oP5mNb4VZHy3Xy8KRZGaQuaOHNhZAT1xaVo6kxjswUi3vYgGJhFMiLuIHdApoc u5f7UbV+egYVxmkvVLSqsVD4pUgHeSoAcIlm3blZ1sDKviJCwaHxDQkVmSsGXImaAU+ViJ5l CwkvyiiIifWD2SoOuFexZyZ7RUddLosgsO0npVUYbl6dEMq2a5ijGF6/rBs1m3nAoIgpXk6P TCKlSWVW6OCneTaKM5C387972qREtiArTakRQIpvDJuiR2soGfdeJ6igGA1FZjU+IsM5ABEB AAHNH1RvbSBkZSBWcmllcyA8dGRldnJpZXNAc3VzZS5kZT7CwKsEEwEIAD4WIQSsnSe5hKbL MK1mGmjuhV2rbOJEoAUCXSW0JwIbAwUJA8JnAAULCQgHAgYVCgkICwIEFgIDAQIeAQIXgAAh CRDuhV2rbOJEoBYhBKydJ7mEpsswrWYaaO6FXats4kSgc48H/Ra2lq5p3dHsrlQLqM7N68Fo eRDf3PMevXyMlrCYDGLVncQwMw3O/AkousktXKQ42DPJh65zoXB22yUt8m0g12xkLax98KFJ 5NyUloa6HflLl+wQL/uZjIdNUQaHQLw3HKwRMVi4l0/Jh/TygYG1Dtm8I4o708JS4y8GQxoQ UL0z1OM9hyM3gI2WVTTyprsBHy2EjMOu/2Xpod95pF8f90zBLajy6qXEnxlcsqreMaqmkzKn 3KTZpWRxNAS/IH3FbGQ+3RpWkNGSJpwfEMVCeyK5a1n7yt1podd1ajY5mA1jcaUmGppqx827 8TqyteNe1B/pbiUt2L/WhnTgW1NC1QDOwE0EXSW0JwEIAM99H34Bu4MKM7HDJVt864MXbx7B 1M93wVlpJ7Uq+XDFD0A0hIal028j+h6jA6bhzWto4RUfDl/9mn1StngNVFovvwtfzbamp6+W pKHZm9X5YvlIwCx131kTxCNDcF+/adRW4n8CU3pZWYmNVqhMUiPLxElA6QhXTtVBh1RkjCZQ Kmbd1szvcOfaD8s+tJABJzNZsmO2hVuFwkDrRN8Jgrh92a+yHQPd9+RybW2l7sJv26nkUH5Z 5s84P6894ebgimcprJdAkjJTgprl1nhgvptU5M9Uv85Pferoh2groQEAtRPlCGrZ2/2qVNe9 XJfSYbiyedvApWcJs5DOByTaKkcAEQEAAcLAkwQYAQgAJhYhBKydJ7mEpsswrWYaaO6FXats 4kSgBQJdJbQnAhsMBQkDwmcAACEJEO6FXats4kSgFiEErJ0nuYSmyzCtZhpo7oVdq2ziRKD3 twf7BAQBZ8TqR812zKAD7biOnWIJ0McV72PFBxmLIHp24UVe0ZogtYMxSWKLg3csh0yLVwc7 H3vldzJ9AoK3Qxp0Q6K/rDOeUy3HMqewQGcqrsRRh0NXDIQk5CgSrZslPe47qIbe3O7ik/MC q31FNIAQJPmKXX25B115MMzkSKlv4udfx7KdyxHrTSkwWZArLQiEZj5KG4cCKhIoMygPTA3U yGaIvI/BGOtHZ7bEBVUCFDFfOWJ26IOCoPnSVUvKPEOH9dv+sNy7jyBsP5QxeTqwxC/1ZtNS DUCSFQjqA6bEGwM22dP8OUY6SC94x1G81A9/xbtm9LQxKm0EiDH8KBMLfQ== Message-ID: Date: Mon, 23 Mar 2020 20:16:54 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <2dc5460f-33b3-227d-6e46-8d8663149931@suse.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-38.0 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_DMARC_STATUS, KAM_SHORT, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 23 Mar 2020 19:16:58 -0000 On 09-03-2020 13:52, Tom de Vries wrote: > On 24-02-2020 21:14, Tom de Vries wrote: >> Hi, >> >> Consider the test-case from this patch, compiled with pthread support: >> ... >> $ gcc src/gdb/testsuite/gdb.threads/hang-after-ext-sigkill.c -lpthread >> ... >> >> After running, the program sleeps: >> ... >> $ gdb a.out >> Reading symbols from a.out... >> (gdb) r >> Starting program: /data/gdb_versions/devel/a.out >> [Thread debugging using libthread_db enabled] >> Using host libthread_db library "/lib64/libthread_db.so.1". >> [New Thread 0x7ffff77fe700 (LWP 22604)] >> ... >> >> Until we interrupt it with a control-C: >> ... >> ^C >> Thread 1 "a.out" received signal SIGINT, Interrupt. >> 0x00007ffff78c50f0 in nanosleep () from /lib64/libc.so.6 >> (gdb) >> ... >> >> If we then kill the inferior using an external SIGKILL: >> ... >> (gdb) shell killall -s SIGKILL a.out >> ... >> and subsequently continue: >> ... >> (gdb) c >> Continuing. >> Couldn't get registers: No such process. >> Couldn't get registers: No such process. >> (gdb) Couldn't get registers: No such process. >> (gdb) Couldn't get registers: No such process. >> (gdb) Couldn't get registers: No such process. >> >> ... >> gdb hangs which repeating the same warning. Typing control-C no longer helps, >> and we have to kill gdb using kill. >> >> This is a regression since commit 873657b9e8 "Preserve selected thread in >> all-stop w/ background execution". The commit adds a >> scoped_restore_current_thread typed variable restore_thread to >> fetch_inferior_event, and the hang is caused by the constructor throwing an >> exception. >> >> Fix this by catching the exception in the constructor. >> >> Build and reg-tested on x86_64-linux. >> >> OK for trunk? >> > Ping^2. Thanks, - Tom > >> [gdb] Fix hang after ext sigkill >> >> gdb/ChangeLog: >> >> 2020-02-24 Tom de Vries >> >> PR gdb/25471 >> * thread.c >> (scoped_restore_current_thread::scoped_restore_current_thread): Catch >> exception in get_frame_id. >> (scoped_restore_current_thread::~scoped_restore_current_thread): >> Handle lack of inferior. >> >> gdb/testsuite/ChangeLog: >> >> 2020-02-24 Tom de Vries >> >> PR gdb/25471 >> * gdb.threads/hang-after-ext-sigkill.c: New test. >> * gdb.threads/hang-after-ext-sigkill.exp: New file. >> * lib/gdb.exp (runto): Handle "Temporary breakpoint" string. >> >> --- >> gdb/testsuite/gdb.threads/hang-after-ext-sigkill.c | 40 ++++++++++++ >> .../gdb.threads/hang-after-ext-sigkill.exp | 73 ++++++++++++++++++++++ >> gdb/testsuite/lib/gdb.exp | 2 +- >> gdb/thread.c | 14 ++++- >> 4 files changed, 127 insertions(+), 2 deletions(-) >> >> diff --git a/gdb/testsuite/gdb.threads/hang-after-ext-sigkill.c b/gdb/testsuite/gdb.threads/hang-after-ext-sigkill.c >> new file mode 100644 >> index 0000000000..bfce6c3085 >> --- /dev/null >> +++ b/gdb/testsuite/gdb.threads/hang-after-ext-sigkill.c >> @@ -0,0 +1,40 @@ >> +/* This testcase is part of GDB, the GNU debugger. >> + >> + Copyright 2020 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 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 . */ >> + >> +#include >> +#include >> + >> +static void * >> +fun (void *dummy) >> +{ >> + while (1) >> + sleep (1); >> + >> + return NULL; >> +} >> + >> +int >> +main (void) >> +{ >> + pthread_t thread; >> + pthread_create (&thread, NULL, fun, NULL); >> + >> + while (1) >> + sleep (1); >> + >> + return 0; >> +} >> diff --git a/gdb/testsuite/gdb.threads/hang-after-ext-sigkill.exp b/gdb/testsuite/gdb.threads/hang-after-ext-sigkill.exp >> new file mode 100644 >> index 0000000000..3702eb8c13 >> --- /dev/null >> +++ b/gdb/testsuite/gdb.threads/hang-after-ext-sigkill.exp >> @@ -0,0 +1,73 @@ >> +# Copyright (C) 2020 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 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 . >> + >> +standard_testfile >> + >> +if {[prepare_for_testing "failed to prepare" $testfile $srcfile \ >> + {pthreads}] == -1} { >> + return -1 >> +} >> + >> +set res [runto main no-message temporary] >> +if { $res != 1 } { >> + return -1 >> +} >> + >> +set pid -1 >> +gdb_test_multiple "info inferior 1" "get inferior pid" { >> + -re -wrap "process (\[0-9\]*).*" { >> + set pid $expect_out(1,string) >> + pass $gdb_test_name >> + } >> +} >> +if { $pid == -1 } { >> + return -1 >> +} >> + >> +gdb_test_multiple "continue" "" { >> + -re "Continuing" { >> + pass $gdb_test_name >> + } >> +} >> + >> +send_gdb "\003" >> + >> +gdb_test_multiple "" "get sigint" { >> + -re -wrap "Thread \[0-9\]+ .* received signal SIGINT, Interrupt\..*" { >> + pass $gdb_test_name >> + } >> +} >> + >> +gdb_test_no_output "shell kill -s SIGKILL $pid" "shell kill -s SIGKILL pid" >> + >> +# Expect the signal to arrive, and the program to terminate. >> +# Ideally at the first continue, currently though at the second. >> +set killed_msg "Program terminated with signal SIGKILL, Killed\." >> +set no_longer_exists_msg "The program no longer exists\." >> +set not_being_run_msg "The program is not being run\." >> +set msg [join [list $killed_msg $no_longer_exists_msg $not_being_run_msg] \ >> + ".*"] >> + >> +# Don't expect '$gdb_prompt $', there still may be output after the prompt, >> +# f.i.: >> +# ... >> +# (gdb) [Thread 0x7ffff74c6700 (LWP 19277) exited]^M >> +# ... >> +gdb_test_multiple "continue" "" { >> + -re ".*\r\n$gdb_prompt " { >> + gdb_test "continue" $msg $gdb_test_name >> + } >> +} >> + >> diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp >> index 81518b9646..745694df2d 100644 >> --- a/gdb/testsuite/lib/gdb.exp >> +++ b/gdb/testsuite/lib/gdb.exp >> @@ -571,7 +571,7 @@ proc runto { function args } { >> } >> return 1 >> } >> - -re "Breakpoint \[0-9\]*, \[0-9xa-f\]* in .*$gdb_prompt $" { >> + -re "\[Bb\]reakpoint \[0-9\]*, \[0-9xa-f\]* in .*$gdb_prompt $" { >> if { $print_pass } { >> pass $test_name >> } >> diff --git a/gdb/thread.c b/gdb/thread.c >> index 54b59e2244..9876ca3c76 100644 >> --- a/gdb/thread.c >> +++ b/gdb/thread.c >> @@ -1444,6 +1444,8 @@ scoped_restore_current_thread::restore () >> >> scoped_restore_current_thread::~scoped_restore_current_thread () >> { >> + if (m_inf == NULL) >> + return; >> if (!m_dont_restore) >> { >> try >> @@ -1488,7 +1490,17 @@ scoped_restore_current_thread::scoped_restore_current_thread () >> else >> frame = NULL; >> >> - m_selected_frame_id = get_frame_id (frame); >> + try >> + { >> + m_selected_frame_id = get_frame_id (frame); >> + } >> + catch (const gdb_exception &ex) >> + { >> + m_inf = NULL; >> + m_selected_frame_id = null_frame_id; >> + m_selected_frame_level = -1; >> + return; >> + } >> m_selected_frame_level = frame_relative_level (frame); >> >> tp->incref (); >>