On Thu, May 1, 2025 at 5:36 PM Andrew Morton [off-list ref] wrote:

On Thu,  1 May 2025 15:54:13 -0700 Changyuan Lyu [off-list ref] wrote:

quoted

From: Arnd Bergmann <arnd@arndb.de>

The early_memremap() function is decleared in a header that is only indirectly
included here:

kernel/kexec_handover.c:1116:8: error: call to undeclared function 'early_memremap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
 1116 |         fdt = early_memremap(fdt_phys, fdt_len);
      |               ^

...

--- a/kernel/kexec_handover.c
+++ b/kernel/kexec_handover.c

@@ -17,6 +17,9 @@
 #include <linux/memblock.h>
 #include <linux/notifier.h>
 #include <linux/page-isolation.h>
+
+#include <asm/early_ioremap.h>
+
 /*
  * KHO is tightly coupled with mm init and needs access to some of mm
  * internal APIs.

When resending, it's best to fold little fixes like this into the base
patch, along with a little note and the author's signed-off-by.

Thanks for the suggestion Andrew! I will follow it next time.

I shall queue this as a fix to be folded into "kexec: add KHO parsing
support", thanks.

Best,
Changyuan