[PATCH] integrity: avoid using __weak functions

[Arnd Bergmann <arnd@kernel.org>]

From: Arnd Bergmann <arnd@arndb.de>

The security/integrity/secure_boot.c file containing only a __weak function
leads to a build failure with clang:

Cannot find symbol for section 2: .text.
security/integrity/secure_boot.o: failed

Moving the function into another file that has at least one non-__weak
symbol would solve this, but this is always fragile.

Avoid __weak definitions entirely and instead move the stub helper into
an asm-generic header that gets used by default on architectures that
do not provide their own version. This is consistent with how a lot
of other architecture specific functionality works, and is more reliable.

Fixes: a0f87ede3bf4 ("integrity: Make arch_ima_get_secureboot integrity-wide")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
This is a larger change than I had hoped for.

If you prefer a different way to address the build failure, please
treat this as a Reported-by when you apply your own fix
---
 arch/powerpc/include/asm/secure_boot.h        |  6 +++
 arch/powerpc/kernel/secure_boot.c             |  1 -
 arch/s390/include/asm/secure_boot.h           |  9 +++++
 include/asm-generic/Kbuild                    |  1 +
 include/asm-generic/secure_boot.h             | 37 +++++++++++++++++++
 include/linux/secure_boot.h                   |  8 +---
 security/integrity/Makefile                   |  2 +-
 .../integrity/platform_certs/load_powerpc.c   |  2 +-
 security/integrity/secure_boot.c              | 16 --------
 9 files changed, 56 insertions(+), 26 deletions(-)
 create mode 100644 arch/s390/include/asm/secure_boot.h
 create mode 100644 include/asm-generic/secure_boot.h
 delete mode 100644 security/integrity/secure_boot.c

diff --git a/arch/powerpc/include/asm/secure_boot.h b/arch/powerpc/include/asm/secure_boot.h
index a2ff556916c6..db72dcdf5bb3 100644
--- a/arch/powerpc/include/asm/secure_boot.h
+++ b/arch/powerpc/include/asm/secure_boot.h
@@ -10,11 +10,17 @@
 
 #ifdef CONFIG_PPC_SECURE_BOOT
 
+bool arch_get_secureboot(void);
 bool is_ppc_secureboot_enabled(void);
 bool is_ppc_trustedboot_enabled(void);
 
 #else
 
+static inline bool arch_get_secureboot(void)
+{
+	return false;
+}
+
 static inline bool is_ppc_secureboot_enabled(void)
 {
 	return false;
diff --git a/arch/powerpc/kernel/secure_boot.c b/arch/powerpc/kernel/secure_boot.c
index 28436c1599e0..e3ea46124180 100644
--- a/arch/powerpc/kernel/secure_boot.c
+++ b/arch/powerpc/kernel/secure_boot.c
@@ -7,7 +7,6 @@
 #include <linux/of.h>
 #include <linux/secure_boot.h>
 #include <linux/string_choices.h>
-#include <asm/secure_boot.h>
 
 static struct device_node *get_ppc_fw_sb_node(void)
 {
diff --git a/arch/s390/include/asm/secure_boot.h b/arch/s390/include/asm/secure_boot.h
new file mode 100644
index 000000000000..4086fdfb9e5c
--- /dev/null
+++ b/arch/s390/include/asm/secure_boot.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_S390_SECURE_BOOT_H
+#define _ASM_S390_SECURE_BOOT_H
+
+#include <linux/types.h
+
+bool arch_get_secureboot(void);
+
+#endif
diff --git a/include/asm-generic/Kbuild b/include/asm-generic/Kbuild
index 0f97f7b594c3..8c0a499141fb 100644
--- a/include/asm-generic/Kbuild
+++ b/include/asm-generic/Kbuild
@@ -51,6 +51,7 @@ mandatory-y += rqspinlock.h
 mandatory-y += runtime-const.h
 mandatory-y += rwonce.h
 mandatory-y += sections.h
+mandatory-y += secure_boot.h
 mandatory-y += serial.h
 mandatory-y += shmparam.h
 mandatory-y += simd.h
diff --git a/include/asm-generic/secure_boot.h b/include/asm-generic/secure_boot.h
new file mode 100644
index 000000000000..08d8e294576c
--- /dev/null
+++ b/include/asm-generic/secure_boot.h
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2026 Red Hat, Inc. All Rights Reserved.
+ *
+ * Author: Coiby Xu <coxu@redhat.com>
+ */
+#ifndef _ASM_SECURE_BOOT_H
+#define _ASM_SECURE_BOOT_H
+
+
+#include <linux/types.h>
+
+#ifdef CONFIG_EFI
+
+/*
+ * Default implementation.
+ * Architectures that support secure boot must override this.
+ *
+ * Returns true if the platform secure boot is enabled.
+ * Returns false if disabled or not supported.
+ */
+bool arch_get_secureboot(void);
+
+#else
+
+/*
+ * Default implementation.
+ * Architectures that support secure boot must override this.
+ */
+static inline bool arch_get_secureboot(void)
+{
+	return false;
+}
+
+#endif
+
+#endif
diff --git a/include/linux/secure_boot.h b/include/linux/secure_boot.h
index 3ded3f03655c..9ddfbe109b1d 100644
--- a/include/linux/secure_boot.h
+++ b/include/linux/secure_boot.h
@@ -8,12 +8,6 @@
 #ifndef _LINUX_SECURE_BOOT_H
 #define _LINUX_SECURE_BOOT_H
 
-#include <linux/types.h>
-
-/*
- * Returns true if the platform secure boot is enabled.
- * Returns false if disabled or not supported.
- */
-bool arch_get_secureboot(void);
+#include <asm/secure_boot.h>
 
 #endif /* _LINUX_SECURE_BOOT_H */
diff --git a/security/integrity/Makefile b/security/integrity/Makefile
index 548665e2b702..45dfdedbdad4 100644
--- a/security/integrity/Makefile
+++ b/security/integrity/Makefile
@@ -5,7 +5,7 @@
 
 obj-$(CONFIG_INTEGRITY) += integrity.o
 
-integrity-y := iint.o secure_boot.o
+integrity-y := iint.o
 integrity-$(CONFIG_INTEGRITY_AUDIT) += integrity_audit.o
 integrity-$(CONFIG_INTEGRITY_SIGNATURE) += digsig.o
 integrity-$(CONFIG_INTEGRITY_ASYMMETRIC_KEYS) += digsig_asymmetric.o
diff --git a/security/integrity/platform_certs/load_powerpc.c b/security/integrity/platform_certs/load_powerpc.c
index 714c961a00f5..ab74e947a8bc 100644
--- a/security/integrity/platform_certs/load_powerpc.c
+++ b/security/integrity/platform_certs/load_powerpc.c
@@ -10,7 +10,7 @@
 #include <linux/cred.h>
 #include <linux/err.h>
 #include <linux/slab.h>
-#include <asm/secure_boot.h>
+#include <linux/secure_boot.h>
 #include <asm/secvar.h>
 #include "keyring_handler.h"
 #include "../integrity.h"
diff --git a/security/integrity/secure_boot.c b/security/integrity/secure_boot.c
deleted file mode 100644
index fc2693c286f8..000000000000
--- a/security/integrity/secure_boot.c
+++ /dev/null
@@ -1,16 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (C) 2026 Red Hat, Inc. All Rights Reserved.
- *
- * Author: Coiby Xu <coxu@redhat.com>
- */
-#include <linux/secure_boot.h>
-
-/*
- * Default weak implementation.
- * Architectures that support secure boot must override this.
- */
-__weak bool arch_get_secureboot(void)
-{
-	return false;
-}
-- 
2.39.5