aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorPeter Zijlstra <peterz@infradead.org>2021-03-18 11:31:51 +0100
committerPeter Zijlstra <peterz@infradead.org>2021-03-19 13:16:44 +0100
commit38c93587375053c5b9ef093f4a5ea754538cba32 (patch)
tree8c6554263f39529cfb04901f006415d4fdb83cac
parent698bacefe993ad2922c9d3b1380591ad489355e9 (diff)
downloadlinux-stericsson-38c93587375053c5b9ef093f4a5ea754538cba32.tar.gz
static_call: Fix static_call_update() sanity check
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
-rw-r--r--kernel/jump_label.c8
-rw-r--r--kernel/static_call.c11
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 fc2259047be2..2c5950b0b90e 100644
--- a/kernel/static_call.c
+++ b/kernel/static_call.c
@@ -181,7 +181,16 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
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;
}