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 server2.sourceware.org (Postfix) with ESMTPS id 707FA394442F for ; Mon, 9 Mar 2020 12:52:25 +0000 (GMT) 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 304FFAF21; Mon, 9 Mar 2020 12:52:24 +0000 (UTC) Subject: [PING][PATCH][gdb] Fix hang after ext sigkill From: Tom de Vries To: gdb-patches@sourceware.org Cc: Pedro Alves References: <20200224201403.GA7079@delia> 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: <2dc5460f-33b3-227d-6e46-8d8663149931@suse.de> Date: Mon, 9 Mar 2020 13:52:23 +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: <20200224201403.GA7079@delia> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS 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, 09 Mar 2020 12:52:26 -0000 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. 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 (); >