systemd/0032-pid1-improve-logging-when-failing-to-remount-ro-5940.patch
Zbigniew Jędrzejewski-Szmek f4a67616bd Backport a bunch of fixes
2017-06-15 10:26:56 -04:00

101 lines
4.5 KiB
Diff

From 207b45b46c41b84cbd2be29331c105308d66b3bd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Thu, 11 May 2017 12:12:41 -0400
Subject: [PATCH] pid1: improve logging when failing to remount / ro (#5940)
https://bugzilla.redhat.com/show_bug.cgi?id=1227736#c49
We counted how many filesystems could not be unmounted, but only for those
filesystems which we tried to unmount. Since we only remount / ro, without
attempting to unmount, we would emit a confusing error message:
Remounting '/' read-only with options 'seclabel,space_cache,subvolid=5,subvol=/'.
Remounting '/' read-only with options 'seclabel,space_cache,subvolid=5,subvol=/'.
Remounting '/' read-only with options 'seclabel,space_cache,subvolid=5,subvol=/'.
All filesystems unmounted.
Warn when remount-ro fails, and for filesystems which we won't try to unmount,
include the failure to remount-ro in n_failed.
A few minor cleanups:
- remove unecessary goto which jumps to the next line anyway
- always calculate n_failed, even if log_error is false. This causes no change
in behaviour, but I think the code is easier to follow, since the log setting
cannot influence other logic.
(cherry picked from commit c826cd3f7cfd950c8a86d57dfa6303f70de3e207)
---
src/core/umount.c | 33 ++++++++++++++++++++-------------
1 file changed, 20 insertions(+), 13 deletions(-)
diff --git a/src/core/umount.c b/src/core/umount.c
index 2f4b12bdb9..77b5bd9556 100644
--- a/src/core/umount.c
+++ b/src/core/umount.c
@@ -369,6 +369,14 @@ static int delete_dm(dev_t devnum) {
return 0;
}
+static bool nonunmountable_path(const char *path) {
+ return path_equal(path, "/")
+#ifndef HAVE_SPLIT_USR
+ || path_equal(path, "/usr")
+#endif
+ || path_startswith(path, "/run/initramfs");
+}
+
static int mount_points_list_umount(MountPoint **head, bool *changed, bool log_error) {
MountPoint *m, *n;
int n_failed = 0;
@@ -404,21 +412,21 @@ static int mount_points_list_umount(MountPoint **head, bool *changed, bool log_e
* somehwere else via a bind mount. If we
* explicitly remount the super block of that
* alias read-only we hence should be
- * relatively safe regarding keeping the fs we
- * can otherwise not see dirty. */
+ * relatively safe regarding keeping dirty an fs
+ * we cannot otherwise see. */
log_info("Remounting '%s' read-only with options '%s'.", m->path, options);
- (void) mount(NULL, m->path, NULL, MS_REMOUNT|MS_RDONLY, options);
+ if (mount(NULL, m->path, NULL, MS_REMOUNT|MS_RDONLY, options) < 0) {
+ if (log_error)
+ log_notice_errno(errno, "Failed to remount '%s' read-only: %m", m->path);
+ if (nonunmountable_path(m->path))
+ n_failed++;
+ }
}
/* Skip / and /usr since we cannot unmount that
* anyway, since we are running from it. They have
* already been remounted ro. */
- if (path_equal(m->path, "/")
-#ifndef HAVE_SPLIT_USR
- || path_equal(m->path, "/usr")
-#endif
- || path_startswith(m->path, "/run/initramfs")
- )
+ if (nonunmountable_path(m->path))
continue;
/* Trying to umount. We don't force here since we rely
@@ -430,8 +438,9 @@ static int mount_points_list_umount(MountPoint **head, bool *changed, bool log_e
*changed = true;
mount_point_free(head, m);
- } else if (log_error) {
- log_warning_errno(errno, "Could not unmount %s: %m", m->path);
+ } else {
+ if (log_error)
+ log_warning_errno(errno, "Could not unmount %s: %m", m->path);
n_failed++;
}
}
@@ -555,8 +564,6 @@ int umount_all(bool *changed) {
/* umount one more time with logging enabled */
r = mount_points_list_umount(&mp_list_head, &umount_changed, true);
- if (r <= 0)
- goto end;
end:
mount_points_list_free(&mp_list_head);