[PATCH v2] powerpc: Implement ARCH_HAS_CC_CAN_LINK

[Thomas Weißschuh]

The generic CC_CAN_LINK detection does not handle different byte orders.
This may lead to userprogs which are not actually runnable on the target
kernel.

Use architecture-specific logic supporting byte orders instead.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh at linutronix.de>
---
Changes in v2:
- Rebase on v7.0-rc1.
- Link to v1: https://lore.kernel.org/r/20251230-cc-can-link-powerpc-v1-1-82298df6e3bf@linutronix.de
---
 arch/powerpc/Kconfig | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index ad7a2fe63a2a..793e6b311143 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -127,6 +127,7 @@ config PPC
 	select ARCH_DMA_DEFAULT_COHERENT	if !NOT_COHERENT_CACHE
 	select ARCH_ENABLE_MEMORY_HOTPLUG
 	select ARCH_ENABLE_MEMORY_HOTREMOVE
+	select ARCH_HAS_CC_CAN_LINK
 	select ARCH_HAS_COPY_MC			if PPC64
 	select ARCH_HAS_CURRENT_STACK_POINTER
 	select ARCH_HAS_DEBUG_VIRTUAL
@@ -1343,6 +1344,20 @@ endif
 config PPC_LIB_RHEAP
 	bool
 
+config ARCH_CC_CAN_LINK
+	bool
+	default $(cc_can_link_user,$(m64-flag) -mlittle-endian) if 64BIT && CPU_LITTLE_ENDIAN
+	default $(cc_can_link_user,$(m64-flag) -mbig-endian) if 64BIT && CPU_BIG_ENDIAN
+	default $(cc_can_link_user,$(m32-flag) -mlittle-endian) if CPU_LITTLE_ENDIAN
+	default $(cc_can_link_user,$(m32-flag) -mbig-endian) if CPU_BIG_ENDIAN
+
+config ARCH_USERFLAGS
+	string
+	default "$(m64-flag) -mlittle-endian" if 64BIT && CPU_LITTLE_ENDIAN
+	default "$(m64-flag) -mbig-endian" if 64BIT && CPU_BIG_ENDIAN
+	default "$(m32-flag) -mlittle-endian" if CPU_LITTLE_ENDIAN
+	default "$(m32-flag) -mbig-endian" if CPU_BIG_ENDIAN
+
 source "arch/powerpc/kvm/Kconfig"
 
 source "kernel/livepatch/Kconfig"

---
base-commit: 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f
change-id: 20251222-cc-can-link-powerpc-5ddd2469fd5b

Best regards,
-- 
Thomas Weißschuh <thomas.weissschuh at linutronix.de>