static_call: Fix static_call_set_init()

It turns out that static_call_set_init() does not preserve the other
flags; IOW. it clears TAIL if it was set.

Fixes: 9183c3f9ed ("static_call: Add inline static call infrastructure")
Reported-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lkml.kernel.org/r/20210318113610.519406371@infradead.org
This commit is contained in:
Peter Zijlstra 2021-03-18 11:27:19 +01:00
parent bee645788e
commit 68b1eddd42

View File

@ -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;
}
@ -190,7 +193,7 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
}
arch_static_call_transform(site_addr, NULL, func,
static_call_is_tail(site));
static_call_is_tail(site));
}
}
@ -349,7 +352,7 @@ static int static_call_add_module(struct module *mod)
struct static_call_site *site;
for (site = start; site != stop; site++) {
unsigned long s_key = (long)site->key + (long)&site->key;
unsigned long s_key = __static_call_key(site);
unsigned long addr = s_key & ~STATIC_CALL_SITE_FLAGS;
unsigned long key;