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| author | Petr Mladek <pmladek@suse.com> | 2019-01-09 13:43:22 +0100 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2019-01-11 20:51:24 +0100 |
| commit | 68007289bf3cd937a5b8fc4987d2787167bd06ca (patch) | |
| tree | 2c913929da4c5e65fcacdfc5afb47399d86cf446 /kernel/livepatch/core.c | |
| parent | livepatch: Consolidate klp_free functions (diff) | |
| download | linux-68007289bf3cd937a5b8fc4987d2787167bd06ca.tar.xz linux-68007289bf3cd937a5b8fc4987d2787167bd06ca.zip | |
livepatch: Don't block the removal of patches loaded after a forced transition
module_put() is currently never called in klp_complete_transition() when
klp_force is set. As a result, we might keep the reference count even when
klp_enable_patch() fails and klp_cancel_transition() is called.
This might give the impression that a module might get blocked in some
strange init state. Fortunately, it is not the case. The reference count
is ignored when mod->init fails and erroneous modules are always removed.
Anyway, this might be confusing. Instead, this patch moves
the global klp_forced flag into struct klp_patch. As a result,
we block only modules that might still be in use after a forced
transition. Newly loaded livepatches might be eventually completely
removed later.
It is not a big deal. But the code is at least consistent with
the reality.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'kernel/livepatch/core.c')
| -rw-r--r-- | kernel/livepatch/core.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 6f0d9095f662..e77c5017ae0c 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -45,7 +45,8 @@ */ DEFINE_MUTEX(klp_mutex); -static LIST_HEAD(klp_patches); +/* Registered patches */ +LIST_HEAD(klp_patches); static struct kobject *klp_root_kobj; @@ -659,6 +660,7 @@ static int klp_init_patch_early(struct klp_patch *patch) INIT_LIST_HEAD(&patch->list); patch->kobj_added = false; patch->enabled = false; + patch->forced = false; init_completion(&patch->finish); klp_for_each_object(patch, obj) { |