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Diffstat (limited to 'kernel/static_call.c')
-rw-r--r--kernel/static_call.c47
1 files changed, 27 insertions, 20 deletions
diff --git a/kernel/static_call.c b/kernel/static_call.c
index 6906c6ec4c97..2c5950b0b90e 100644
--- a/kernel/static_call.c
+++ b/kernel/static_call.c
@@ -35,27 +35,30 @@ static inline void *static_call_addr(struct static_call_site *site)
return (void *)((long)site->addr + (long)&site->addr);
}
+static inline unsigned long __static_call_key(const struct static_call_site *site)
+{
+ return (long)site->key + (long)&site->key;
+}
static inline struct static_call_key *static_call_key(const struct static_call_site *site)
{
- return (struct static_call_key *)
- (((long)site->key + (long)&site->key) & ~STATIC_CALL_SITE_FLAGS);
+ return (void *)(__static_call_key(site) & ~STATIC_CALL_SITE_FLAGS);
}
/* These assume the key is word-aligned. */
static inline bool static_call_is_init(struct static_call_site *site)
{
- return ((long)site->key + (long)&site->key) & STATIC_CALL_SITE_INIT;
+ return __static_call_key(site) & STATIC_CALL_SITE_INIT;
}
static inline bool static_call_is_tail(struct static_call_site *site)
{
- return ((long)site->key + (long)&site->key) & STATIC_CALL_SITE_TAIL;
+ return __static_call_key(site) & STATIC_CALL_SITE_TAIL;
}
static inline void static_call_set_init(struct static_call_site *site)
{
- site->key = ((long)static_call_key(site) | STATIC_CALL_SITE_INIT) -
+ site->key = (__static_call_key(site) | STATIC_CALL_SITE_INIT) -
(long)&site->key;
}
@@ -146,6 +149,7 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
};
for (site_mod = &first; site_mod; site_mod = site_mod->next) {
+ bool init = system_state < SYSTEM_RUNNING;
struct module *mod = site_mod->mod;
if (!site_mod->sites) {
@@ -165,6 +169,7 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
if (mod) {
stop = mod->static_call_sites +
mod->num_static_call_sites;
+ init = mod->state == MODULE_STATE_COMING;
}
#endif
@@ -172,25 +177,26 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
site < stop && static_call_key(site) == key; site++) {
void *site_addr = static_call_addr(site);
- if (static_call_is_init(site)) {
- /*
- * Don't write to call sites which were in
- * initmem and have since been freed.
- */
- if (!mod && system_state >= SYSTEM_RUNNING)
- continue;
- if (mod && !within_module_init((unsigned long)site_addr, mod))
- continue;
- }
+ if (!init && static_call_is_init(site))
+ continue;
if (!kernel_text_address((unsigned long)site_addr)) {
- WARN_ONCE(1, "can't patch static call site at %pS",
+ /*
+ * This skips patching built-in __exit, which
+ * is part of init_section_contains() but is
+ * not part of kernel_text_address().
+ *
+ * Skipping built-in __exit is fine since it
+ * will never be executed.
+ */
+ WARN_ONCE(!static_call_is_init(site),
+ "can't patch static call site at %pS",
site_addr);
continue;
}
arch_static_call_transform(site_addr, NULL, func,
- static_call_is_tail(site));
+ static_call_is_tail(site));
}
}
@@ -349,7 +355,8 @@ static int static_call_add_module(struct module *mod)
struct static_call_site *site;
for (site = start; site != stop; site++) {
- unsigned long addr = (unsigned long)static_call_key(site);
+ unsigned long s_key = __static_call_key(site);
+ unsigned long addr = s_key & ~STATIC_CALL_SITE_FLAGS;
unsigned long key;
/*
@@ -373,8 +380,8 @@ static int static_call_add_module(struct module *mod)
return -EINVAL;
}
- site->key = (key - (long)&site->key) |
- (site->key & STATIC_CALL_SITE_FLAGS);
+ key |= s_key & STATIC_CALL_SITE_FLAGS;
+ site->key = key - (long)&site->key;
}
return __static_call_init(mod, start, stop);