diff options
Diffstat (limited to 'app-emulation/libvirt/files/libvirt-7.3.0-vircgroup-Fix-virCgroupKillRecursive-wrt-nested-cont.patch')
| -rw-r--r-- | app-emulation/libvirt/files/libvirt-7.3.0-vircgroup-Fix-virCgroupKillRecursive-wrt-nested-cont.patch | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/app-emulation/libvirt/files/libvirt-7.3.0-vircgroup-Fix-virCgroupKillRecursive-wrt-nested-cont.patch b/app-emulation/libvirt/files/libvirt-7.3.0-vircgroup-Fix-virCgroupKillRecursive-wrt-nested-cont.patch new file mode 100644 index 000000000000..69572b321cfb --- /dev/null +++ b/app-emulation/libvirt/files/libvirt-7.3.0-vircgroup-Fix-virCgroupKillRecursive-wrt-nested-cont.patch @@ -0,0 +1,189 @@ +From ea7d0ca37cce76e1327945c4864b996d7fd6d2e6 Mon Sep 17 00:00:00 2001 +Message-Id: <ea7d0ca37cce76e1327945c4864b996d7fd6d2e6.1618903455.git.mprivozn@redhat.com> +From: Michal Privoznik <mprivozn@redhat.com> +Date: Fri, 16 Apr 2021 16:39:14 +0200 +Subject: [PATCH] vircgroup: Fix virCgroupKillRecursive() wrt nested + controllers +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +I've encountered the following bug, but only on Gentoo with +systemd and CGroupsV2. I've started an LXC container successfully +but destroying it reported the following error: + + error: Failed to destroy domain 'amd64' + error: internal error: failed to get cgroup backend for 'pathOfController' + +Debugging showed, that CGroup hierarchy is full of surprises: + +/sys/fs/cgroup/machine.slice/machine-lxc\x2d861\x2damd64.scope/ +└── libvirt + ├── dev-hugepages.mount + ├── dev-mqueue.mount + ├── init.scope + ├── sys-fs-fuse-connections.mount + ├── sys-kernel-config.mount + ├── sys-kernel-debug.mount + ├── sys-kernel-tracing.mount + ├── system.slice + │ ├── console-getty.service + │ ├── dbus.service + │ ├── system-getty.slice + │ ├── system-modprobe.slice + │ ├── systemd-journald.service + │ ├── systemd-logind.service + │ └── tmp.mount + └── user.slice + +For comparison, here's the same container on recent Rawhide: + +/sys/fs/cgroup/machine.slice/machine-lxc\x2d13550\x2damd64.scope/ +└── libvirt + +Anyway, those nested directories should not be a problem, because +virCgroupKillRecursiveInternal() removes them recursively, right? +Sort of. The function really does remove nested directories, but +it assumes that every directory has the same controller as the +rest. Just take a look at virCgroupV2KillRecursive() - it gets +'Any' controller (the first one it found in ".scope") and then +passes it to virCgroupKillRecursiveInternal(). + +This assumption is not true though. The controllers found in +".scope" are the following: + + cpuset cpu io memory pids + +while "libvirt" has fewer: + + cpuset cpu io memory + +Up until now it's not problem, because of how we order +controllers internally - "cpu" is the first and thus picking +"Any" controller returns just that. But the rest of directories +has no controllers, their "cgroup.controllers" is just empty. + +What fixes the bug is dropping @controller argument from +virCgroupKillRecursiveInternal() and letting each iteration work +pick its own controller. + +Signed-off-by: Michal Privoznik <mprivozn@redhat.com> +Reviewed-by: Pavel Hrdina <phrdina@redhat.com> +--- + src/util/vircgroup.c | 25 +++++++++++++++++++++++-- + src/util/vircgrouppriv.h | 1 - + src/util/vircgroupv1.c | 7 +------ + src/util/vircgroupv2.c | 7 +------ + 4 files changed, 25 insertions(+), 15 deletions(-) + +diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c +index 96280a0a4e..37dde2a5ed 100644 +--- a/src/util/vircgroup.c ++++ b/src/util/vircgroup.c +@@ -1477,6 +1477,24 @@ virCgroupHasController(virCgroup *cgroup, int controller) + } + + ++static int ++virCgroupGetAnyController(virCgroup *cgroup) ++{ ++ size_t i; ++ ++ for (i = 0; i < VIR_CGROUP_BACKEND_TYPE_LAST; i++) { ++ if (!cgroup->backends[i]) ++ continue; ++ ++ return cgroup->backends[i]->getAnyController(cgroup); ++ } ++ ++ virReportError(VIR_ERR_INTERNAL_ERROR, "%s", ++ _("Unable to get any controller")); ++ return -1; ++} ++ ++ + int + virCgroupPathOfController(virCgroup *group, + unsigned int controller, +@@ -2715,11 +2733,11 @@ int + virCgroupKillRecursiveInternal(virCgroup *group, + int signum, + GHashTable *pids, +- int controller, + const char *taskFile, + bool dormdir) + { + int rc; ++ int controller; + bool killedAny = false; + g_autofree char *keypath = NULL; + g_autoptr(DIR) dp = NULL; +@@ -2728,6 +2746,9 @@ virCgroupKillRecursiveInternal(virCgroup *group, + VIR_DEBUG("group=%p signum=%d pids=%p taskFile=%s dormdir=%d", + group, signum, pids, taskFile, dormdir); + ++ if ((controller = virCgroupGetAnyController(group)) < 0) ++ return -1; ++ + if (virCgroupPathOfController(group, controller, "", &keypath) < 0) + return -1; + +@@ -2760,7 +2781,7 @@ virCgroupKillRecursiveInternal(virCgroup *group, + return -1; + + if ((rc = virCgroupKillRecursiveInternal(subgroup, signum, pids, +- controller, taskFile, true)) < 0) ++ taskFile, true)) < 0) + return -1; + if (rc == 1) + killedAny = true; +diff --git a/src/util/vircgrouppriv.h b/src/util/vircgrouppriv.h +index 00193fb101..caf7ed84db 100644 +--- a/src/util/vircgrouppriv.h ++++ b/src/util/vircgrouppriv.h +@@ -135,6 +135,5 @@ int virCgroupRemoveRecursively(char *grppath); + int virCgroupKillRecursiveInternal(virCgroup *group, + int signum, + GHashTable *pids, +- int controller, + const char *taskFile, + bool dormdir); +diff --git a/src/util/vircgroupv1.c b/src/util/vircgroupv1.c +index 2cc7dd386a..8a04bb2e4a 100644 +--- a/src/util/vircgroupv1.c ++++ b/src/util/vircgroupv1.c +@@ -812,12 +812,7 @@ virCgroupV1KillRecursive(virCgroup *group, + int signum, + GHashTable *pids) + { +- int controller = virCgroupV1GetAnyController(group); +- +- if (controller < 0) +- return -1; +- +- return virCgroupKillRecursiveInternal(group, signum, pids, controller, ++ return virCgroupKillRecursiveInternal(group, signum, pids, + "tasks", false); + } + +diff --git a/src/util/vircgroupv2.c b/src/util/vircgroupv2.c +index e555217355..8881d3a88a 100644 +--- a/src/util/vircgroupv2.c ++++ b/src/util/vircgroupv2.c +@@ -577,12 +577,7 @@ virCgroupV2KillRecursive(virCgroup *group, + int signum, + GHashTable *pids) + { +- int controller = virCgroupV2GetAnyController(group); +- +- if (controller < 0) +- return -1; +- +- return virCgroupKillRecursiveInternal(group, signum, pids, controller, ++ return virCgroupKillRecursiveInternal(group, signum, pids, + "cgroup.threads", false); + } + +-- +2.26.3 + |