Based on Serge Hallyn's patch: "Trivial patch, and I'm not sure whether we want this or want to do it this way. But it saves me having to do it during my restart.sh wrapper shell-script."
Make sure that the old /dev/pts is un-mounted prior to the mount of the new one. Signed-off-by: Oren Laadan <[email protected]> --- restart.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 files changed, 40 insertions(+), 0 deletions(-) diff --git a/restart.c b/restart.c index f42b456..e3c4a5c 100644 --- a/restart.c +++ b/restart.c @@ -53,6 +53,7 @@ static char usage_str[] = " --signal=SIG send SIG to root task on SIGINT (default: SIGKILL\n" " to container root, SIGINT otherwise)\n" " --mntns restart under a private mounts namespace\n" +" --mount-pty start in a new devpts namespace to supprt ptys\n" " -w,--wait wait for root task to termiate (default)\n" " --show-status show exit status of root task (implies -w)\n" " --copy-status imitate exit status of root task (implies -w)\n" @@ -275,6 +276,7 @@ int global_send_sigint = -1; int global_sent_sigint; static int ckpt_remount_proc(void); +static int ckpt_remount_devpts(void); static int ckpt_build_tree(struct ckpt_ctx *ctx); static int ckpt_init_tree(struct ckpt_ctx *ctx); @@ -342,6 +344,7 @@ struct args { char *root; int wait; int mntns; + int mnt_pty; int show_status; int copy_status; char *freezer; @@ -432,6 +435,7 @@ static void parse_args(struct args *args, int argc, char *argv[]) { "debug", no_argument, NULL, 'd' }, { "warn-pidzero", no_argument, NULL, 9 }, { "fail-pidzero", no_argument, NULL, 10 }, + { "mount-pty", no_argument, NULL, 12 }, { NULL, 0, NULL, 0 } }; static char optc[] = "hdvkpPwWF:r:i:l:"; @@ -538,6 +542,9 @@ static void parse_args(struct args *args, int argc, char *argv[]) case 11: args->mntns = 1; break; + case 12: + args->mnt_pty = 1; + break; default: usage(usage_str); } @@ -591,6 +598,9 @@ static void parse_args(struct args *args, int argc, char *argv[]) printf("Invalid used of both -l/--logfile and --logfile-fd\n"); exit(1); } + + if (args->mnt_pty) + args->mntns = 1; } static void report_exit_status(int status, char *str, int debug) @@ -785,6 +795,10 @@ int main(int argc, char *argv[]) exit(1); } + /* remount /dev/pts ? */ + if (args.mnt_pty && ckpt_remount_devpts() < 0) + exit(1); + /* self-restart ends here: */ if (args.self) { restart(getpid(), STDIN_FILENO, RESTART_TASKSELF, args.logfd); @@ -916,6 +930,32 @@ static int ckpt_collect_child(struct ckpt_ctx *ctx) return ckpt_parse_status(status, mimic, verbose); } +static int ckpt_remount_devpts(void) +{ + struct stat ptystat; + + /* make sure /dev/ptmx is a link else we'll just break */ + if (lstat("/dev/ptmx", &ptystat) < 0) { + perror("stat /dev/ptmx"); + return -1; + } + if ((ptystat.st_mode & S_IFMT) != S_IFLNK) { + ckpt_err("Error: /dev/ptmx must be a link to /dev/pts/ptmx\n"); + return -1; + } + + if (umount2("/dev/pts", MNT_DETACH) < 0) { + perror("umount -l /dev/pts"); + return -1; + } + if (mount("pts", "/dev/pts", "devpts", 0, "newinstance") < 0) { + perror("mount -t devpts -o newinstance"); + return -1; + } + + return 0; +} + static int ckpt_close_files(void) { char fdpath[64], *endp; -- 1.6.3.3 _______________________________________________ Containers mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
