---

yaml
---
r: 48897
b: refs/heads/master
c: c587e4a
h: refs/heads/master
i:
  48895: ce2f884
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 3b581f5485c180016a6c36c4c7007e21c53f8a63
+refs/heads/master: c587e4a6a4d808fd2a1c4e7fb2d5a3a31e300d23

trunk/arch/arm/Kconfig

@@ -738,6 +738,20 @@ config XIP_PHYS_ADDR
 	  be linked for and stored to.  This address is dependent on your
 	  own flash usage.
 
+config KEXEC
+	bool "Kexec system call (EXPERIMENTAL)"
+	depends on EXPERIMENTAL
+	help
+	  kexec is a system call that implements the ability to shutdown your
+	  current kernel, and to start another kernel.  It is like a reboot
+	  but it is indepedent of the system firmware.   And like a reboot
+	  you can start any kernel with it, not just Linux.
+
+	  It is an ongoing process to be certain the hardware in a machine
+	  is properly shutdown, so do not be surprised if this code does not
+	  initially work for you.  It may help to enable device hotplugging
+	  support.
+
 endmenu
 
 if (ARCH_SA1100 || ARCH_INTEGRATOR || ARCH_OMAP || ARCH_IMX )

trunk/arch/arm/kernel/Makefile

@@ -19,6 +19,7 @@ obj-$(CONFIG_ARTHUR)		+= arthur.o
 obj-$(CONFIG_ISA_DMA)		+= dma-isa.o
 obj-$(CONFIG_PCI)		+= bios32.o isa.o
 obj-$(CONFIG_SMP)		+= smp.o
+obj-$(CONFIG_KEXEC)		+= machine_kexec.o relocate_kernel.o
 obj-$(CONFIG_OABI_COMPAT)	+= sys_oabi-compat.o
 
 obj-$(CONFIG_CRUNCH)		+= crunch.o crunch-bits.o

trunk/arch/arm/kernel/calls.S

@@ -356,6 +356,7 @@
 		CALL(sys_move_pages)
 /* 345 */	CALL(sys_getcpu)
 		CALL(sys_ni_syscall)		/* eventually epoll_pwait */
+		CALL(sys_kexec_load)
 #ifndef syscalls_counted
 .equ syscalls_padding, ((NR_syscalls + 3) & ~3) - NR_syscalls
 #define syscalls_counted

trunk/arch/arm/kernel/machine_kexec.c

@@ -0,0 +1,78 @@
+/*
+ * machine_kexec.c - handle transition of Linux booting another kernel
+ */
+
+#include <linux/mm.h>
+#include <linux/kexec.h>
+#include <linux/delay.h>
+#include <linux/reboot.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/mmu_context.h>
+#include <asm/io.h>
+#include <asm/cacheflush.h>
+#include <asm/mach-types.h>
+
+const extern unsigned char relocate_new_kernel[];
+const extern unsigned int relocate_new_kernel_size;
+
+extern void setup_mm_for_reboot(char mode);
+
+extern unsigned long kexec_start_address;
+extern unsigned long kexec_indirection_page;
+extern unsigned long kexec_mach_type;
+
+/*
+ * Provide a dummy crash_notes definition while crash dump arrives to arm.
+ * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
+ */
+
+int machine_kexec_prepare(struct kimage *image)
+{
+	return 0;
+}
+
+void machine_kexec_cleanup(struct kimage *image)
+{
+}
+
+void machine_shutdown(void)
+{
+}
+
+void machine_crash_shutdown(struct pt_regs *regs)
+{
+}
+
+void machine_kexec(struct kimage *image)
+{
+	unsigned long page_list;
+	unsigned long reboot_code_buffer_phys;
+	void *reboot_code_buffer;
+
+
+	page_list = image->head & PAGE_MASK;
+
+	/* we need both effective and real address here */
+	reboot_code_buffer_phys =
+	    page_to_pfn(image->control_code_page) << PAGE_SHIFT;
+	reboot_code_buffer = page_address(image->control_code_page);
+
+	/* Prepare parameters for reboot_code_buffer*/
+	kexec_start_address = image->start;
+	kexec_indirection_page = page_list;
+	kexec_mach_type = machine_arch_type;
+
+	/* copy our kernel relocation code to the control code page */
+	memcpy(reboot_code_buffer,
+	       relocate_new_kernel, relocate_new_kernel_size);
+
+
+	flush_icache_range((unsigned long) reboot_code_buffer,
+			   (unsigned long) reboot_code_buffer + KEXEC_CONTROL_CODE_SIZE);
+	printk(KERN_INFO "Bye!\n");
+
+	cpu_proc_fin();
+	setup_mm_for_reboot(0); /* mode is not used, so just pass 0*/
+	cpu_reset(reboot_code_buffer_phys);
+}

trunk/arch/arm/kernel/relocate_kernel.S

@@ -0,0 +1,74 @@
+/*
+ * relocate_kernel.S - put the kernel image in place to boot
+ */
+
+#include <asm/kexec.h>
+
+	.globl relocate_new_kernel
+relocate_new_kernel:
+
+	ldr	r0,kexec_indirection_page
+	ldr	r1,kexec_start_address
+
+
+0:	/* top, read another word for the indirection page */
+	ldr	r3, [r0],#4
+
+	/* Is it a destination page. Put destination address to r4 */
+	tst	r3,#1,0
+	beq	1f
+	bic	r4,r3,#1
+	b	0b
+1:
+	/* Is it an indirection page */
+	tst	r3,#2,0
+	beq	1f
+	bic	r0,r3,#2
+	b	0b
+1:
+
+	/* are we done ? */
+	tst	r3,#4,0
+	beq	1f
+	b	2f
+
+1:
+	/* is it source ? */
+	tst	r3,#8,0
+	beq	0b
+	bic r3,r3,#8
+	mov r6,#1024
+9:
+	ldr r5,[r3],#4
+	str r5,[r4],#4
+	subs r6,r6,#1
+	bne 9b
+	b 0b
+
+2:
+	/* Jump to relocated kernel */
+	mov lr,r1
+	mov r0,#0
+	ldr r1,kexec_mach_type
+	mov r2,#0
+	mov pc,lr
+
+	.globl kexec_start_address
+kexec_start_address:
+	.long	0x0
+
+	.globl kexec_indirection_page
+kexec_indirection_page:
+	.long	0x0
+
+	.globl kexec_mach_type
+kexec_mach_type:
+	.long	0x0
+
+relocate_new_kernel_end:
+
+	.globl relocate_new_kernel_size
+relocate_new_kernel_size:
+	.long relocate_new_kernel_end - relocate_new_kernel
+
+

trunk/include/asm-arm/kexec.h

@@ -0,0 +1,30 @@
+#ifndef _ARM_KEXEC_H
+#define _ARM_KEXEC_H
+
+#ifdef CONFIG_KEXEC
+
+/* Maximum physical address we can use pages from */
+#define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
+/* Maximum address we can reach in physical address mode */
+#define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
+/* Maximum address we can use for the control code buffer */
+#define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE
+
+#define KEXEC_CONTROL_CODE_SIZE	4096
+
+#define KEXEC_ARCH KEXEC_ARCH_ARM
+
+#ifndef __ASSEMBLY__
+
+#define MAX_NOTE_BYTES 1024
+
+struct kimage;
+/* Provide a dummy definition to avoid build failures. */
+static inline void crash_setup_regs(struct pt_regs *newregs,
+                                        struct pt_regs *oldregs) { }
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* CONFIG_KEXEC */
+
+#endif /* _ARM_KEXEC_H */

trunk/include/asm-arm/unistd.h

@@ -372,6 +372,7 @@
 #define __NR_move_pages			(__NR_SYSCALL_BASE+344)
 #define __NR_getcpu			(__NR_SYSCALL_BASE+345)
 					/* 346 for epoll_pwait */
+#define __NR_sys_kexec_load		(__NR_SYSCALL_BASE+347)
 
 /*
  * The following SWIs are ARM private.

trunk/include/linux/kexec.h

@@ -125,6 +125,7 @@ extern struct kimage *kexec_crash_image;
 #define KEXEC_ARCH_PPC     (20 << 16)
 #define KEXEC_ARCH_PPC64   (21 << 16)
 #define KEXEC_ARCH_IA_64   (50 << 16)
+#define KEXEC_ARCH_ARM     (40 << 16)
 #define KEXEC_ARCH_S390    (22 << 16)
 #define KEXEC_ARCH_SH      (42 << 16)
 #define KEXEC_ARCH_MIPS_LE (10 << 16)