meta-openembedded/meta-initramfs/recipes-kernel/kexec/kexec-tools-klibc/0006-kexec-syscall.h-work-around-missing-syscall-wrapper.patch

From ab24f236cbc0aa8a3eadde5d71d9d7ea1d979a51 Mon Sep 17 00:00:00 2001
From: Andrea Adami <andrea.adami@gmail.com>
Date: Fri, 31 Aug 2018 11:33:51 +0200
Subject: [PATCH] kexec-syscall.h: work around missing syscall() wrapper

Fix

 kexec-syscall.h: In function 'kexec_load':
 kexec-syscall.h:80:16: warning: implicit declaration of function 'syscall'

Upstream-Status: Inappropriate [klibc specific]
Signed-off-by: Andrea Adami <andrea.adami@gmail.com>

---
 kexec/kexec-syscall.h | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/kexec/kexec-syscall.h b/kexec/kexec-syscall.h
index b96e02a..2a3794d 100644
--- a/kexec/kexec-syscall.h
+++ b/kexec/kexec-syscall.h
@@ -77,11 +77,16 @@
 
 struct kexec_segment;
 
+#ifndef __KLIBC__
 static inline long kexec_load(void *entry, unsigned long nr_segments,
 			struct kexec_segment *segments, unsigned long flags)
 {
 	return (long) syscall(__NR_kexec_load, entry, nr_segments, segments, flags);
 }
+#else
+extern long kexec_load(void *entry, unsigned long nr_segments,
+			struct kexec_segment *segments, unsigned long flags);
+#endif
 
 static inline int is_kexec_file_load_implemented(void) {
 	if (__NR_kexec_file_load != 0xffffffff)
@@ -89,6 +94,21 @@ static inline int is_kexec_file_load_implemented(void) {
 	return 0;
 }
 
+#ifdef __KLIBC__
+/* Stub provided by klibc only for the following archs */
+#if defined (__x86_64__) || defined (__powerpc_64__) || defined (__s390x__)
+extern long kexec_file_load(int kernel_fd, int initrd_fd,
+			unsigned long cmdline_len, const char *cmdline_ptr,
+			unsigned long flags);
+#else
+static inline long kexec_file_load(int kernel_fd, int initrd_fd,
+			unsigned long cmdline_len, const char *cmdline_ptr,
+			unsigned long flags)
+{
+	return -1;
+}
+#endif
+#else
 static inline long kexec_file_load(int kernel_fd, int initrd_fd,
 			unsigned long cmdline_len, const char *cmdline_ptr,
 			unsigned long flags)
@@ -96,6 +116,7 @@ static inline long kexec_file_load(int kernel_fd, int initrd_fd,
 	return (long) syscall(__NR_kexec_file_load, kernel_fd, initrd_fd,
 				cmdline_len, cmdline_ptr, flags);
 }
+#endif
 
 #define KEXEC_ON_CRASH		0x00000001
 #define KEXEC_PRESERVE_CONTEXT	0x00000002