From ab9293f69f97c8147fbf4554906e7258e67e2017b758bc36392bb1f01e620829 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Cristian=20Rodr=C3=ADguez?= Date: Tue, 20 Nov 2012 17:57:51 +0000 Subject: [PATCH] Accepting request 142164 from home:fcrozat:branches:Base:System - Add remount-ro-before-unmount.patch: always remount read-only before unmounting in final shutdown loop. - Add switch-root-try-pivot-root.patch: try pivot_root before overmounting / OBS-URL: https://build.opensuse.org/request/show/142164 OBS-URL: https://build.opensuse.org/package/show/Base:System/systemd?expand=0&rev=313 --- remount-ro-before-unmount.patch | 95 ++++++++++++++++++++++++++++++++ switch-root-try-pivot-root.patch | 81 +++++++++++++++++++++++++++ systemd-mini.changes | 8 +++ systemd-mini.spec | 6 ++ systemd.changes | 8 +++ systemd.spec | 6 ++ 6 files changed, 204 insertions(+) create mode 100644 remount-ro-before-unmount.patch create mode 100644 switch-root-try-pivot-root.patch diff --git a/remount-ro-before-unmount.patch b/remount-ro-before-unmount.patch new file mode 100644 index 00000000..d634afff --- /dev/null +++ b/remount-ro-before-unmount.patch @@ -0,0 +1,95 @@ +From 93bd157722c76b47d80742f290373c1ce2865070 Mon Sep 17 00:00:00 2001 +From: Lennart Poettering +Date: Fri, 16 Nov 2012 18:36:28 +0100 +Subject: [PATCH] umount: always remount read-only before unmounting in final + shutdown loop + +--- + src/core/umount.c | 57 +++++++++++++++++++++++++---------------------------- + 1 file changed, 27 insertions(+), 30 deletions(-) + +diff --git a/src/core/umount.c b/src/core/umount.c +index 83c9de3..e794057 100644 +--- a/src/core/umount.c ++++ b/src/core/umount.c +@@ -407,6 +407,33 @@ static int mount_points_list_umount(MountPoint **head, bool *changed, bool log_e + assert(head); + + LIST_FOREACH_SAFE(mount_point, m, n, *head) { ++ ++ /* If we are in a container, don't attempt to ++ read-only mount anything as that brings no real ++ benefits, but might confuse the host, as we remount ++ the superblock here, not the bind mound. */ ++ if (detect_container(NULL) <= 0) { ++ /* We always try to remount directories ++ * read-only first, before we go on and umount ++ * them. ++ * ++ * Mount points can be stacked. If a mount ++ * point is stacked below / or /usr, we ++ * cannnot umount or remount it directly, ++ * since there is no way to refer to the ++ * underlying mount. There's nothing we can do ++ * about it for the general case, but we can ++ * do something about it if it is aliased ++ * 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. */ ++ mount(NULL, m->path, NULL, MS_REMOUNT|MS_RDONLY, NULL); ++ } ++ ++ /* Skip / and /usr since we cannot unmount that ++ * anyway, since we are running from it */ + if (path_equal(m->path, "/") + #ifndef HAVE_SPLIT_USR + || path_equal(m->path, "/usr") +@@ -432,29 +459,6 @@ static int mount_points_list_umount(MountPoint **head, bool *changed, bool log_e + return n_failed; + } + +-static int mount_points_list_remount_read_only(MountPoint **head, bool *changed) { +- MountPoint *m, *n; +- int n_failed = 0; +- +- assert(head); +- +- LIST_FOREACH_SAFE(mount_point, m, n, *head) { +- +- /* Trying to remount read-only */ +- if (mount(NULL, m->path, NULL, MS_REMOUNT|MS_RDONLY, NULL) == 0) { +- if (changed) +- *changed = true; +- +- mount_point_free(head, m); +- } else { +- log_warning("Could not remount as read-only %s: %m", m->path); +- n_failed++; +- } +- } +- +- return n_failed; +-} +- + static int swap_points_list_off(MountPoint **head, bool *changed) { + MountPoint *m, *n; + int n_failed = 0; +@@ -571,13 +575,6 @@ int umount_all(bool *changed) { + if (r <= 0) + goto end; + +- /* If we are in a container, don't attempt to read-only mount +- anything as that brings no real benefits, but might confuse +- the host, as we remount the superblock here, not the bind +- mound. */ +- if (detect_container(NULL) <= 0) +- r = mount_points_list_remount_read_only(&mp_list_head, changed); +- + end: + mount_points_list_free(&mp_list_head); + +-- +1.7.10.4 + diff --git a/switch-root-try-pivot-root.patch b/switch-root-try-pivot-root.patch new file mode 100644 index 00000000..d2347eda --- /dev/null +++ b/switch-root-try-pivot-root.patch @@ -0,0 +1,81 @@ +From 891a4918ef75fa81e22691156c050d061bd53dd3 Mon Sep 17 00:00:00 2001 +From: Lennart Poettering +Date: Fri, 16 Nov 2012 18:15:30 +0100 +Subject: [PATCH] switch-root: try pivot_root() before overmounting / + +We should always try to umount the old root dir if possible, instead of +overmounting it -- if that's possible. + +The initial ("first") kernel rootfs can never be umounted, hence +for the usual nitrd case we never bothered using pivot_root() and +hence with fully unmounting it. However, fedup now tranisitions twice +during boot, and in that case it is highly desirable that the "second" +root dir is entirely unmounted when we switch to the "third". This patch +makes that possible. + +The pivot_root() needs a directory in the "third" root dir, to move the +"second" root dir to. We use /mnt for that, under the assumption that +this directory is likely to exist, and is not itself a mount point. +--- + src/core/switch-root.c | 27 ++++++++++++++++++++++++++- + 1 file changed, 26 insertions(+), 1 deletion(-) + +diff --git a/src/core/switch-root.c b/src/core/switch-root.c +index 150332a..ce0e41d 100644 +--- a/src/core/switch-root.c ++++ b/src/core/switch-root.c +@@ -30,6 +30,7 @@ + #include "util.h" + #include "path-util.h" + #include "switch-root.h" ++#include "missing.h" + + int switch_root(const char *new_root) { + +@@ -44,10 +45,21 @@ int switch_root(const char *new_root) { + struct stat new_root_stat; + bool old_root_remove; + const char *i; ++ _cleanup_free_ char *temporary_old_root = NULL; + + if (path_equal(new_root, "/")) + return 0; + ++ /* When using pivot_root() we assume that /mnt exists as place ++ * we can temporarily move the old root to. As we immediately ++ * unmount it from there it doesn't matter much which ++ * directory we choose for this, but it should be more likely ++ * than not that /mnt exists and is suitable as mount point ++ * and is on the same fs as the old root dir */ ++ temporary_old_root = strappend(new_root, "/mnt"); ++ if (!temporary_old_root) ++ return -ENOMEM; ++ + old_root_remove = in_initrd(); + + if (stat(new_root, &new_root_stat) < 0) { +@@ -103,7 +115,20 @@ int switch_root(const char *new_root) { + log_warning("Failed to open root directory: %m"); + } + +- if (mount(new_root, "/", NULL, MS_MOVE, NULL) < 0) { ++ /* We first try a pivot_root() so that we can umount the old ++ * root dir. In many cases (i.e. where rootfs is /), that's ++ * not possible however, and hence we simply overmount root */ ++ if (pivot_root(new_root, temporary_old_root) >= 0) { ++ ++ /* Immediately get rid of the old root. Since we are ++ * running off it we need to do this lazily. */ ++ if (umount2(temporary_old_root, MNT_DETACH) < 0) { ++ r = -errno; ++ log_error("Failed to umount old root dir %s: %m", temporary_old_root); ++ goto fail; ++ } ++ ++ } else if (mount(new_root, "/", NULL, MS_MOVE, NULL) < 0) { + r = -errno; + log_error("Failed to mount moving %s to /: %m", new_root); + goto fail; +-- +1.7.10.4 + diff --git a/systemd-mini.changes b/systemd-mini.changes index dfb64551..11df0f5b 100644 --- a/systemd-mini.changes +++ b/systemd-mini.changes @@ -1,3 +1,11 @@ +------------------------------------------------------------------- +Tue Nov 20 18:25:49 CET 2012 - fcrozat@suse.com + +- Add remount-ro-before-unmount.patch: always remount read-only + before unmounting in final shutdown loop. +- Add switch-root-try-pivot-root.patch: try pivot_root before + overmounting / + ------------------------------------------------------------------- Tue Nov 20 09:36:43 UTC 2012 - fcrozat@suse.com diff --git a/systemd-mini.spec b/systemd-mini.spec index e1b21842..a82dbd62 100644 --- a/systemd-mini.spec +++ b/systemd-mini.spec @@ -148,6 +148,10 @@ Patch66: fix-dbus-crash.patch Patch67: sync-on-shutdown.patch # PATCH-FIX-UPSTREAM mount-efivars.patch fcrozat@suse.com -- mount efivars if booting under UEFI Patch68: mount-efivars.patch +# PATCH-FIX-UPSTREAM switch-root-try-pivot-root.patch fcrozat@suse.com -- try pivot_root before overmounting / +Patch69: switch-root-try-pivot-root.patch +# PATCH-FIX-UPSTREAM remount-ro-before-unmount.patch fcrozat@suse.com -- remount ro before unmounting in final shutdown loop +Patch70: remount-ro-before-unmount.patch # udev patches # PATCH-FIX-OPENSUSE 0001-Reinstate-TIMEOUT-handling.patch @@ -353,6 +357,8 @@ cp %{SOURCE7} m4/ %patch66 -p1 %patch67 -p1 %patch68 -p1 +%patch69 -p1 +%patch70 -p1 %build autoreconf -fiv diff --git a/systemd.changes b/systemd.changes index dfb64551..11df0f5b 100644 --- a/systemd.changes +++ b/systemd.changes @@ -1,3 +1,11 @@ +------------------------------------------------------------------- +Tue Nov 20 18:25:49 CET 2012 - fcrozat@suse.com + +- Add remount-ro-before-unmount.patch: always remount read-only + before unmounting in final shutdown loop. +- Add switch-root-try-pivot-root.patch: try pivot_root before + overmounting / + ------------------------------------------------------------------- Tue Nov 20 09:36:43 UTC 2012 - fcrozat@suse.com diff --git a/systemd.spec b/systemd.spec index f9afc0d1..4012f184 100644 --- a/systemd.spec +++ b/systemd.spec @@ -143,6 +143,10 @@ Patch66: fix-dbus-crash.patch Patch67: sync-on-shutdown.patch # PATCH-FIX-UPSTREAM mount-efivars.patch fcrozat@suse.com -- mount efivars if booting under UEFI Patch68: mount-efivars.patch +# PATCH-FIX-UPSTREAM switch-root-try-pivot-root.patch fcrozat@suse.com -- try pivot_root before overmounting / +Patch69: switch-root-try-pivot-root.patch +# PATCH-FIX-UPSTREAM remount-ro-before-unmount.patch fcrozat@suse.com -- remount ro before unmounting in final shutdown loop +Patch70: remount-ro-before-unmount.patch # udev patches # PATCH-FIX-OPENSUSE 0001-Reinstate-TIMEOUT-handling.patch @@ -348,6 +352,8 @@ cp %{SOURCE7} m4/ %patch66 -p1 %patch67 -p1 %patch68 -p1 +%patch69 -p1 +%patch70 -p1 %build autoreconf -fiv