diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2021-03-18 11:31:51 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-24 11:54:18 +0100 |
| commit | e446086b3309d3ada5638f71f41cf6e832dca978 (patch) | |
| tree | 92ce4186d43e8cb099b9ef0d499698b023cafbc5 | |
| parent | 76957cc2d2874371bd114a89d9fe506867326b04 (diff) | |
static_call: Fix static_call_update() sanity check
commit 38c93587375053c5b9ef093f4a5ea754538cba32 upstream.
Sites that match init_section_contains() get marked as INIT. For
built-in code init_sections contains both __init and __exit text. OTOH
kernel_text_address() only explicitly includes __init text (and there
are no __exit text markers).
Match what jump_label already does and ignore the warning for INIT
sites. Also see the excellent changelog for commit: 8f35eaa5f2de
("jump_label: Don't warn on __exit jump entries")
Fixes: 9183c3f9ed710 ("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/20210318113610.739542434@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | kernel/jump_label.c | 8 | ||||
| -rw-r--r-- | kernel/static_call.c | 11 |
2 files changed, 18 insertions, 1 deletions
diff --git a/kernel/jump_label.c b/kernel/jump_label.c index c6a39d662935..ba39fbb1f8e7 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -407,6 +407,14 @@ static bool jump_label_can_update(struct jump_entry *entry, bool init) return false; if (!kernel_text_address(jump_entry_code(entry))) { + /* + * 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(!jump_entry_is_init(entry), "can't patch jump_label at %pS", (void *)jump_entry_code(entry)); diff --git a/kernel/static_call.c b/kernel/static_call.c index 84565c2a41b8..db914da6e785 100644 --- a/kernel/static_call.c +++ b/kernel/static_call.c @@ -182,7 +182,16 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func) } 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; } |