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[patch+8.0.1] Fix T-stopped detach regression on old kernels
- From: Jan Kratochvil <jan dot kratochvil at redhat dot com>
- To: gdb-patches at sourceware dot org
- Date: Wed, 30 Aug 2017 21:14:17 +0200
- Subject: [patch+8.0.1] Fix T-stopped detach regression on old kernels
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Hi,
https://sourceware.org/bugzilla/show_bug.cgi?id=22046
On <=RHEL6 hosts Fedora/RHEL GDB started to 'kill -STOP' all processes it detached. Even those not originally T-stopped. This is a Fedora-specific patch which is based on upstream GDB's PROC_STATE_STOPPED state.
I believe (I did not verify) this patch did regress it:
commit d617208bb06bd461b52ce041d89f7127e3044762
Author: Pedro Alves <palves@redhat.com>
Date: Mon Jul 25 12:42:17 2016 +0100
linux-procfs: Introduce enum proc_state
As originally there was strstr() but now there is strcmp() and so the missing trailing '\n' no longer matches.
The Bug was found by Michal Kolar.
Reproducibility:
$ gdb -p $PID
(gdb) quit
$ ...
Actual results:
===
RHEL6.9 x86_64 # scl enable devtoolset-7 bash
RHEL6.9 x86_64 # which gdb
/opt/rh/devtoolset-7/root/usr/bin/gdb
RHEL6.9 x86_64 # ./testcase.sh
24737 pts/0 S+ 0:00 /bin/sleep 4
24737 pts/0 T+ 0:00 /bin/sleep 4
RHEL6.9 x86_64 #
===
Expected results:
===
RHEL6.9 x86_64 # which gdb
/usr/bin/gdb
RHEL6.9 x86_64 # ./testcase.sh
24708 pts/0 S+ 0:00 /bin/sleep 4
24708 pts/0 S+ 0:00 /bin/sleep 4
./testcase.sh: line 20: kill: (24708) - No such process
RHEL6.9 x86_64 #
===
Tested: 5b86dbf4549af98c4428da4764182e03f22c58ab
OK for check-in?
Jan
2017-08-30 Jan Kratochvil <jan.kratochvil@redhat.com>
* nat/linux-procfs.c (parse_proc_status_state): Fix PROC_STATE_STOPPED
detection.
diff --git a/gdb/nat/linux-procfs.c b/gdb/nat/linux-procfs.c
index a12f6228cb..cca35cbf1d 100644
--- a/gdb/nat/linux-procfs.c
+++ b/gdb/nat/linux-procfs.c
@@ -104,10 +104,10 @@ parse_proc_status_state (const char *state)
return PROC_STATE_TRACING_STOP;
case 'T':
/* Before Linux 2.6.33, tracing stop used uppercase T. */
- if (strcmp (state, "T (tracing stop)") == 0)
- return PROC_STATE_TRACING_STOP;
- else
+ if (strcmp (state, "T (stopped)\n") == 0)
return PROC_STATE_STOPPED;
+ else /* "T (tracing stop)\n" */
+ return PROC_STATE_TRACING_STOP;
case 'X':
return PROC_STATE_DEAD;
case 'Z':