mirror of
https://github.com/espressif/binutils-gdb.git
synced 2025-06-22 19:09:31 +08:00
f50bf8e515
This patch fixes a GDBserver crash when one thread is stepping over a syscall instruction which is exit. Step-over isn't finished due to the exit, but GDBserver doesn't clean up the state of step-over, so in the wait next time, GDBserver will wait on step_over_bkpt, which is already exited, and GDBserver crashes because 'requested_child' is NULL. See gdbserver logs below, Need step over [LWP 14858]? yes, found breakpoint at 0x2aaaaad91307^M proceed_all_lwps: found thread 14858 needing a step-over^M Starting step-over on LWP 14858. Stopping all threads^M >>>> entering void stop_all_lwps(int, lwp_info*) .... <<<< exiting void stop_all_lwps(int, lwp_info*)^M Done stopping all threads for step-over.^M pc is 0x2aaaaad91307^M Writing 0f to 0x2aaaaad91307 in process 14858^M Could not find fast tracepoint jump at 0x2aaaaad91307 in list (uninserting).^M pending reinsert at 0x2aaaaad91307^M step from pc 0x2aaaaad91307^M Resuming lwp 14858 (step, signal 0, stop not expected)^M # Start step-over for LWP 14858 >>>> entering ptid_t linux_wait_1(ptid_t, target_waitstatus*, int) .... LLFE: 14858 exited. ... <<<< exiting ptid_t linux_wait_1(ptid_t, target_waitstatus*, int) # LWP 14858 exited ..... >>>> entering ptid_t linux_wait_1(ptid_t, target_waitstatus*, int)^M linux_wait_1: [<all threads>]^M step_over_bkpt set [LWP 14858.14858], doing a blocking wait # but step_over_bkpt is still LWP 14858, which is wrong The fix is to finish step-over if it is ongoing, and unsuspend other threads. Without the fix in linux-low.c, GDBserver will crash in with running gdb.base/step-over-exit.exp. gdb/gdbserver: 2016-06-17 Yao Qi <yao.qi@linaro.org> * linux-low.c (unsuspend_all_lwps): Declare. (linux_low_filter_event): If thread exited, call finish_step_over. If step-over is finished, unsuspend other threads. gdb/testsuite: 2016-06-17 Yao Qi <yao.qi@linaro.org> * gdb.base/step-over-exit.c: New. * gdb.base/step-over-exit.exp: New.
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.