From: Peter Zijlstra <pet...@infradead.org>

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.g...@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
Acked-by: Jarkko Sakkinen <jar...@kernel.org>
Tested-by: Sumit Garg <sumit.g...@linaro.org>
Link: https://lkml.kernel.org/r/20210318113610.739542...@infradead.org
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 kernel/jump_label.c  |    8 ++++++++
 kernel/static_call.c |   11 ++++++++++-
 2 files changed, 18 insertions(+), 1 deletion(-)

--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -407,6 +407,14 @@ static bool jump_label_can_update(struct
                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));
--- a/kernel/static_call.c
+++ b/kernel/static_call.c
@@ -182,7 +182,16 @@ void __static_call_update(struct static_
                        }
 
                        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;
                        }


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