The following commit has been merged into the locking/urgent branch of tip:
Commit-ID: e48a12e546ecbfb0718176037eae0ad60598a29a
Gitweb: https://git.kernel.org/tip/e48a12e546ecbfb0718176037eae0ad60598a29a
Author: Ingo Molnar <[email protected]>
AuthorDate: Tue, 13 Jul 2021 06:16:05 +02:00
Committer: Ingo Molnar <[email protected]>
CommitterDate: Tue, 13 Jul 2021 06:32:05 +02:00
jump_labels: Mark __jump_label_transform() as __always_inlined to work around aggressive compiler un-inlining
In randconfig testing, certain UBSAN and CC Kconfig combinations
with GCC 10.3.0:
CONFIG_X86_32=y
CONFIG_CC_OPTIMIZE_FOR_SIZE=y
CONFIG_UBSAN=y
# CONFIG_UBSAN_TRAP is not set
# CONFIG_UBSAN_BOUNDS is not set
CONFIG_UBSAN_SHIFT=y
# CONFIG_UBSAN_DIV_ZERO is not set
CONFIG_UBSAN_UNREACHABLE=y
CONFIG_UBSAN_BOOL=y
# CONFIG_UBSAN_ENUM is not set
# CONFIG_UBSAN_ALIGNMENT is not set
# CONFIG_UBSAN_SANITIZE_ALL is not set
... produce this build warning (and build error if
CONFIG_SECTION_MISMATCH_WARN_ONLY=y is set):
WARNING: modpost: vmlinux.o(.text+0x4c1cc): Section mismatch in reference from the function __jump_label_transform() to the function .init.text:text_poke_early()
The function __jump_label_transform() references
the function __init text_poke_early().
This is often because __jump_label_transform lacks a __init
annotation or the annotation of text_poke_early is wrong.
ERROR: modpost: Section mismatches detected.
The problem is that __jump_label_transform() gets uninlined by GCC,
despite there being only a single local scope user of the 'static inline'
function.
Mark the function __always_inline instead, to work around this compiler
bug/artifact.
Signed-off-by: Ingo Molnar <[email protected]>
---
arch/x86/kernel/jump_label.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c
index 674906f..68f091b 100644
--- a/arch/x86/kernel/jump_label.c
+++ b/arch/x86/kernel/jump_label.c
@@ -79,9 +79,10 @@ __jump_label_patch(struct jump_entry *entry, enum jump_label_type type)
return (struct jump_label_patch){.code = code, .size = size};
}
-static inline void __jump_label_transform(struct jump_entry *entry,
- enum jump_label_type type,
- int init)
+static __always_inline void
+__jump_label_transform(struct jump_entry *entry,
+ enum jump_label_type type,
+ int init)
{
const struct jump_label_patch jlp = __jump_label_patch(entry, type);