gdb/mi: Fix segfault when attaching a rocm process with MI
When using the MI interpreter, if someone was to attach to a ROCm
process which has active GPU waves, GDB would issue a segfault as
follows:
attach 1994813
&"attach 1994813\n"
~"Attaching to process 1994813\n"
=thread-group-started,id="i1",pid="1994813"
=thread-created,id="1",group-id="i1"
=thread-created,id="2",group-id="i1"
~"[New LWP 1994828]\n"
*running,thread-id="2"
=thread-created,id="3",group-id="i1"
~"[New LWP 1994825]\n"
*running,thread-id="3"
=thread-created,id="4",group-id="i1"
~"[New LWP 1994823]\n"
*running,thread-id="4"
^done
=library-loaded,...
[...]
~"[Thread debugging using libthread_db enabled]\n"
~"Using host libthread_db library \"/lib/x86_64-linux-gnu/libthread_db.so.1\".\n"
=thread-created,id="5",group-id="i1"
&"\n\n"
&"Fatal signal: "
&"Segmentation fault"
&"\n"
&"----- Backtrace -----\n"
&"Backtrace unavailable\n"
&"---------------------\n"
&"A fatal error internal to GDB has been detected, further\ndebugging is not possible. GDB will now terminate.\n\n"
&"This is a bug, please report it."
&" For instructions, see:\n"
&"<https://github.com/ROCm-Developer-Tools/ROCgdb/issues>"
&"."
&"\n\n"
Segmentation fault
The issue comes from using a non-initialized pointer in mi_on_resume_1:
if (!mi->running_result_record_printed && mi->mi_proceeded)
{
gdb_printf (mi->raw_stdout, "%s^running\n",
mi->current_token ? mi->current_token : "");
}
In this instance, "mi->current_token" has an uninitialized value. This is a
regression introduced by:
commit def2803789208a617c429b5dcf2026decb25ce0c
Date: Wed Sep 6 11:02:00 2023 -0400
gdb/mi: make current_token a field of mi_interp
Before this patch, current_token was a global implicitly 0-initialized. Since
it is now a class field, it is not 0-initialized by default anymore. This
patch changes this.
Change-Id: I3f00b080318a70405d881ff0abe02b2c5cb1f9d8
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Approved-By: Tom Tromey <tom@tromey.com>
3 files changed
