diff options
Diffstat (limited to 'kernel/jump_label.c')
-rw-r--r-- | kernel/jump_label.c | 107 |
1 files changed, 51 insertions, 56 deletions
diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 2e62503bea0d..b28028b08d44 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -38,23 +38,43 @@ static int jump_label_cmp(const void *a, const void *b) const struct jump_entry *jea = a; const struct jump_entry *jeb = b; - if (jea->key < jeb->key) + if (jump_entry_key(jea) < jump_entry_key(jeb)) return -1; - if (jea->key > jeb->key) + if (jump_entry_key(jea) > jump_entry_key(jeb)) return 1; return 0; } +static void jump_label_swap(void *a, void *b, int size) +{ + long delta = (unsigned long)a - (unsigned long)b; + struct jump_entry *jea = a; + struct jump_entry *jeb = b; + struct jump_entry tmp = *jea; + + jea->code = jeb->code - delta; + jea->target = jeb->target - delta; + jea->key = jeb->key - delta; + + jeb->code = tmp.code + delta; + jeb->target = tmp.target + delta; + jeb->key = tmp.key + delta; +} + static void jump_label_sort_entries(struct jump_entry *start, struct jump_entry *stop) { unsigned long size; + void *swapfn = NULL; + + if (IS_ENABLED(CONFIG_HAVE_ARCH_JUMP_LABEL_RELATIVE)) + swapfn = jump_label_swap; size = (((unsigned long)stop - (unsigned long)start) / sizeof(struct jump_entry)); - sort(start, size, sizeof(struct jump_entry), jump_label_cmp, NULL); + sort(start, size, sizeof(struct jump_entry), jump_label_cmp, swapfn); } static void jump_label_update(struct static_key *key); @@ -85,6 +105,7 @@ void static_key_slow_inc_cpuslocked(struct static_key *key) int v, v1; STATIC_KEY_CHECK_USE(key); + lockdep_assert_cpus_held(); /* * Careful if we get concurrent static_key_slow_inc() calls; @@ -130,6 +151,7 @@ EXPORT_SYMBOL_GPL(static_key_slow_inc); void static_key_enable_cpuslocked(struct static_key *key) { STATIC_KEY_CHECK_USE(key); + lockdep_assert_cpus_held(); if (atomic_read(&key->enabled) > 0) { WARN_ON_ONCE(atomic_read(&key->enabled) != 1); @@ -160,6 +182,7 @@ EXPORT_SYMBOL_GPL(static_key_enable); void static_key_disable_cpuslocked(struct static_key *key) { STATIC_KEY_CHECK_USE(key); + lockdep_assert_cpus_held(); if (atomic_read(&key->enabled) != 1) { WARN_ON_ONCE(atomic_read(&key->enabled) != 0); @@ -185,6 +208,8 @@ static void __static_key_slow_dec_cpuslocked(struct static_key *key, unsigned long rate_limit, struct delayed_work *work) { + lockdep_assert_cpus_held(); + /* * The negative count check is valid even when a negative * key->enabled is in use by static_key_slow_inc(); a @@ -261,8 +286,8 @@ EXPORT_SYMBOL_GPL(jump_label_rate_limit); static int addr_conflict(struct jump_entry *entry, void *start, void *end) { - if (entry->code <= (unsigned long)end && - entry->code + JUMP_LABEL_NOP_SIZE > (unsigned long)start) + if (jump_entry_code(entry) <= (unsigned long)end && + jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE > (unsigned long)start) return 1; return 0; @@ -321,16 +346,6 @@ static inline void static_key_set_linked(struct static_key *key) key->type |= JUMP_TYPE_LINKED; } -static inline struct static_key *jump_entry_key(struct jump_entry *entry) -{ - return (struct static_key *)((unsigned long)entry->key & ~1UL); -} - -static bool jump_entry_branch(struct jump_entry *entry) -{ - return (unsigned long)entry->key & 1UL; -} - /*** * A 'struct static_key' uses a union such that it either points directly * to a table of 'struct jump_entry' or to a linked list of modules which in @@ -355,7 +370,7 @@ static enum jump_label_type jump_label_type(struct jump_entry *entry) { struct static_key *key = jump_entry_key(entry); bool enabled = static_key_enabled(key); - bool branch = jump_entry_branch(entry); + bool branch = jump_entry_is_branch(entry); /* See the comment in linux/jump_label.h */ return enabled ^ branch; @@ -363,19 +378,20 @@ static enum jump_label_type jump_label_type(struct jump_entry *entry) static void __jump_label_update(struct static_key *key, struct jump_entry *entry, - struct jump_entry *stop) + struct jump_entry *stop, + bool init) { for (; (entry < stop) && (jump_entry_key(entry) == key); entry++) { /* * An entry->code of 0 indicates an entry which has been * disabled because it was in an init text area. */ - if (entry->code) { - if (kernel_text_address(entry->code)) + if (init || !jump_entry_is_init(entry)) { + if (kernel_text_address(jump_entry_code(entry))) arch_jump_label_transform(entry, jump_label_type(entry)); else WARN_ONCE(1, "can't patch jump_label at %pS", - (void *)(unsigned long)entry->code); + (void *)jump_entry_code(entry)); } } } @@ -410,6 +426,9 @@ void __init jump_label_init(void) if (jump_label_type(iter) == JUMP_LABEL_NOP) arch_jump_label_transform_static(iter, JUMP_LABEL_NOP); + if (init_section_contains((void *)jump_entry_code(iter), 1)) + jump_entry_set_init(iter); + iterk = jump_entry_key(iter); if (iterk == key) continue; @@ -422,26 +441,13 @@ void __init jump_label_init(void) cpus_read_unlock(); } -/* Disable any jump label entries in __init/__exit code */ -void __init jump_label_invalidate_initmem(void) -{ - struct jump_entry *iter_start = __start___jump_table; - struct jump_entry *iter_stop = __stop___jump_table; - struct jump_entry *iter; - - for (iter = iter_start; iter < iter_stop; iter++) { - if (init_section_contains((void *)(unsigned long)iter->code, 1)) - iter->code = 0; - } -} - #ifdef CONFIG_MODULES static enum jump_label_type jump_label_init_type(struct jump_entry *entry) { struct static_key *key = jump_entry_key(entry); bool type = static_key_type(key); - bool branch = jump_entry_branch(entry); + bool branch = jump_entry_is_branch(entry); /* See the comment in linux/jump_label.h */ return type ^ branch; @@ -455,7 +461,7 @@ struct static_key_mod { static inline struct static_key_mod *static_key_mod(struct static_key *key) { - WARN_ON_ONCE(!(key->type & JUMP_TYPE_LINKED)); + WARN_ON_ONCE(!static_key_linked(key)); return (struct static_key_mod *)(key->type & ~JUMP_TYPE_MASK); } @@ -514,7 +520,8 @@ static void __jump_label_mod_update(struct static_key *key) stop = __stop___jump_table; else stop = m->jump_entries + m->num_jump_entries; - __jump_label_update(key, mod->entries, stop); + __jump_label_update(key, mod->entries, stop, + m && m->state == MODULE_STATE_COMING); } } @@ -560,12 +567,15 @@ static int jump_label_add_module(struct module *mod) for (iter = iter_start; iter < iter_stop; iter++) { struct static_key *iterk; + if (within_module_init(jump_entry_code(iter), mod)) + jump_entry_set_init(iter); + iterk = jump_entry_key(iter); if (iterk == key) continue; key = iterk; - if (within_module(iter->key, mod)) { + if (within_module((unsigned long)key, mod)) { static_key_set_entries(key, iter); continue; } @@ -595,7 +605,7 @@ static int jump_label_add_module(struct module *mod) /* Only update if we've changed from our initial state */ if (jump_label_type(iter) != jump_label_init_type(iter)) - __jump_label_update(key, iter, iter_stop); + __jump_label_update(key, iter, iter_stop, true); } return 0; @@ -615,7 +625,7 @@ static void jump_label_del_module(struct module *mod) key = jump_entry_key(iter); - if (within_module(iter->key, mod)) + if (within_module((unsigned long)key, mod)) continue; /* No memory during module load */ @@ -651,19 +661,6 @@ static void jump_label_del_module(struct module *mod) } } -/* Disable any jump label entries in module init code */ -static void jump_label_invalidate_module_init(struct module *mod) -{ - struct jump_entry *iter_start = mod->jump_entries; - struct jump_entry *iter_stop = iter_start + mod->num_jump_entries; - struct jump_entry *iter; - - for (iter = iter_start; iter < iter_stop; iter++) { - if (within_module_init(iter->code, mod)) - iter->code = 0; - } -} - static int jump_label_module_notify(struct notifier_block *self, unsigned long val, void *data) @@ -685,9 +682,6 @@ jump_label_module_notify(struct notifier_block *self, unsigned long val, case MODULE_STATE_GOING: jump_label_del_module(mod); break; - case MODULE_STATE_LIVE: - jump_label_invalidate_module_init(mod); - break; } jump_label_unlock(); @@ -757,7 +751,8 @@ static void jump_label_update(struct static_key *key) entry = static_key_entries(key); /* if there are no users, entry can be NULL */ if (entry) - __jump_label_update(key, entry, stop); + __jump_label_update(key, entry, stop, + system_state < SYSTEM_RUNNING); } #ifdef CONFIG_STATIC_KEYS_SELFTEST |