From 874d3404cbf2363604106c8f86683db4082691ea Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 23 Jan 2015 13:44:44 +0100 Subject: [PATCH] core,shutdown: don't bother with unmounting any mounts below /sys, /proc, /dev when shutting down After all, mounts below these directories are pretty much guaranteed to be virtual, and it's hence unnecessary to unmount them during shutdown. Moreover, in less-priviliged containers we might lack the rights to unmount them, hence don't even try. http://lists.freedesktop.org/archives/systemd-devel/2015-January/027113.html --- src/core/mount.c | 17 ++++++++++++----- src/core/umount.c | 10 ++++++++-- 2 files changed, 20 insertions(+), 7 deletions(-) diff --git a/src/core/mount.c b/src/core/mount.c index 612d150..f944c02 100644 --- a/src/core/mount.c +++ b/src/core/mount.c @@ -378,13 +378,20 @@ static int mount_add_default_dependencies(Mount *m) { if (UNIT(m)->manager->running_as != SYSTEMD_SYSTEM) return 0; - p = get_mount_parameters(m); - - if (!p) + /* We do not add any default dependencies to / and /usr, since + * they are guaranteed to stay mounted the whole time, since + * our system is on it. Also, don't bother with anything + * mounted below virtual file systems, it's also going to be + * virtual, and hence not worth the effort. */ + if (path_equal(m->where, "/") || + path_equal(m->where, "/usr") || + path_startswith(m->where, "/proc") || + path_startswith(m->where, "/sys") || + path_startswith(m->where, "/dev")) return 0; - if (path_equal(m->where, "/") || - path_equal(m->where, "/usr")) + p = get_mount_parameters(m); + if (!p) return 0; if (mount_is_network(p)) { diff --git a/src/core/umount.c b/src/core/umount.c index e38851d..dd7df19 100644 --- a/src/core/umount.c +++ b/src/core/umount.c @@ -104,10 +104,16 @@ static int mount_points_list_get(MountPoint **head) { /* Ignore mount points we can't unmount because they * are API or because we are keeping them open (like - * /dev/console) */ + * /dev/console). Also, ignore all mounts below API + * file systems, since they are likely virtual too, + * and hence not worth spending time on. Also, in + * unprivileged containers we might lack the rights to + * unmount these things, hence don't bother. */ if (mount_point_is_api(p) || mount_point_ignore(p) || - path_equal(p, "/dev/console")) { + path_startswith(p, "/dev") || + path_startswith(p, "/sys") || + path_startswith(p, "/proc")) { free(p); continue; } -- 2.7.4