From 988427829bcd230c78106d28dbfa85d45d182909 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Tue, 27 Jan 2015 12:10:04 -0600 Subject: [PATCH] ktest: Restore tty settings after closing console When ktest runs the console program as a child process, the parent and child share the same tty for stdin and stderr. This is problematic when using a libvirt target. The "virsh console" program makes a lot of changes to the tty settings, making ktest's output hard to read (carriage returns don't work). After ktest exits, the terminal is unusable (CRs broken, stdin isn't echoed). I think the best way to fix this issue would be to create a pseudoterminal (pty pair) so the child process would have a dedicated tty, and then use pipes to connect the two ttys. I'm not sure if that's overkill, but it's far beyond my current Perl abilities. This patch is a much easier way to (partially) fix this issue. It saves the tty settings before opening the console and restores them after closing it. There are still a few places where ktest prints mangled output while the console is open, but the output is much more legible overall, and the terminal works just fine after ktest exits. Link: http://lkml.kernel.org/r/1bb89abc0025cf1d6da657c7ba58bbeb4381a515.1422382008.git.jpoimboe@redhat.com Signed-off-by: Josh Poimboeuf Signed-off-by: Steven Rostedt --- tools/testing/ktest/ktest.pl | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/tools/testing/ktest/ktest.pl b/tools/testing/ktest/ktest.pl index 27273c228d92..1dae000f79f8 100755 --- a/tools/testing/ktest/ktest.pl +++ b/tools/testing/ktest/ktest.pl @@ -178,6 +178,7 @@ my $checkout; my $localversion; my $iteration = 0; my $successes = 0; +my $stty; my $bisect_good; my $bisect_bad; @@ -1349,6 +1350,9 @@ sub open_console { my $flags; + # save terminal settings + $stty = `stty -g`; + my $pid = open($fp, "$console|") or dodie "Can't open console $console"; @@ -1368,6 +1372,9 @@ sub close_console { print "closing!\n"; close($fp); + + # restore terminal settings + system("stty $stty"); } sub start_monitor {