Subject: Re: linux-next: build warning after merge of the arm64 tree

From: Catalin Marinas <[email-masked]>
Date: Tue, 24 Oct 2023 10:55:18 +0100

+ Ard

On Tue, Oct 24, 2023 at 05:24:09PM +1100, Stephen Rothwell wrote:
> After merging the arm64 tree, today's linux-next build (arm64 defconfig)
> produced this warning:
> 
> WARNING: modpost: vmlinux: section mismatch in reference: __pi_$x+0x38 (section: .text) -> __pi_map_range (section: .init.text)
> 
> I don't know what caused this.

For some reason, building linux-next doesn't inline all the functions in
the map_range.c file and we end up with some of them in different
sections. I didn't get this when building the arm64 for-next/core
separately.

My fix (I'll push it to the arm64 branch):

diff --git a/arch/arm64/kernel/pi/map_kernel.c b/arch/arm64/kernel/pi/map_kernel.c
index be7caf07bfa7..e07f3ece5430 100644
--- a/arch/arm64/kernel/pi/map_kernel.c
+++ b/arch/arm64/kernel/pi/map_kernel.c
@@ -20,17 +20,17 @@ extern const u8 __eh_frame_start[], __eh_frame_end[];

 extern void idmap_cpu_replace_ttbr1(void *pgdir);

-static void map_segment(pgd_t *pg_dir, u64 *pgd, u64 va_offset,
-			void *start, void *end, pgprot_t prot,
-			bool may_use_cont, int root_level)
+static void __init map_segment(pgd_t *pg_dir, u64 *pgd, u64 va_offset,
+			       void *start, void *end, pgprot_t prot,
+			       bool may_use_cont, int root_level)
 {
 	map_range(pgd, ((u64)start + va_offset) & ~PAGE_OFFSET,
 		  ((u64)end + va_offset) & ~PAGE_OFFSET, (u64)start,
 		  prot, root_level, (pte_t *)pg_dir, may_use_cont, 0);
 }

-static void unmap_segment(pgd_t *pg_dir, u64 va_offset, void *start,
-			  void *end, int root_level)
+static void __init unmap_segment(pgd_t *pg_dir, u64 va_offset, void *start,
+				 void *end, int root_level)
 {
 	map_segment(pg_dir, NULL, va_offset, start, end, __pgprot(0),
 		    false, root_level);
@@ -205,7 +205,7 @@ static void __init remap_idmap_for_lpa2(void)
 	memset(init_pg_dir, 0, (u64)init_pg_end - (u64)init_pg_dir);
 }

-static void map_fdt(u64 fdt)
+static void __init map_fdt(u64 fdt)
 {
 	static u8 ptes[INIT_IDMAP_FDT_SIZE] __initdata __aligned(PAGE_SIZE);
 	u64 efdt = fdt + MAX_FDT_SIZE;

-- 
Catalin