kexec based crashdumps

diff -puN arch/i386/boot/compressed/misc.c~kd-kern-offset arch/i386/boot/compressed/misc.c
@@ -14,6 +14,7 @@
 #include <linux/tty.h>
 #include <video/edid.h>
 #include <asm/io.h>
+#include <asm/segment.h>
 
 /*
  * gzip declarations

@@ -309,7 +310,7 @@ static void setup_normal_output_buffer(v
 #else
 	if ((RM_ALT_MEM_K > RM_EXT_MEM_K ? RM_ALT_MEM_K : RM_EXT_MEM_K) < 1024) error("Less than 2MB of memory");
 #endif
-	output_data = (char *)0x100000; /* Points to 1M */
+	output_data = (char *)KERN_PHYS_OFFSET; /* Points to 1M */
 	free_mem_end_ptr = (long)real_mode;
 }
 

@@ -334,8 +335,8 @@ static void setup_output_buffer_if_we_ru
 	low_buffer_size = low_buffer_end - LOW_BUFFER_START;
 	high_loaded = 1;
 	free_mem_end_ptr = (long)high_buffer_start;
-	if ( (0x100000 + low_buffer_size) > ((ulg)high_buffer_start)) {
-		high_buffer_start = (uch *)(0x100000 + low_buffer_size);
+	if ( (KERN_PHYS_OFFSET + low_buffer_size) > ((ulg)high_buffer_start)) {
+		high_buffer_start = (uch *)(KERN_PHYS_OFFSET + low_buffer_size);
 		mv->hcount = 0; /* say: we need not to move high_buffer */
 	}
 	else mv->hcount = -1;

diff -puN include/asm-i386/segment.h~kd-kern-offset include/asm-i386/segment.h
@@ -95,4 +95,6 @@
  */
 #define IDT_ENTRIES 256
 
+#define KERN_PHYS_OFFSET (CONFIG_KERN_PHYS_OFFSET * 0x100000)
+
 #endif

diff -puN include/asm-generic/vmlinux.lds.h~kd-kern-offset include/asm-generic/vmlinux.lds.h
@@ -70,7 +70,7 @@
 	}
 
 #define SECURITY_INIT							\
-	.security_initcall.init : {					\
+	.security_initcall.init : AT(ADDR(.security_initcall.init) - LOAD_OFFSET) {\
 		VMLINUX_SYMBOL(__security_initcall_start) = .;		\
 		*(.security_initcall.init) 				\
 		VMLINUX_SYMBOL(__security_initcall_end) = .;		\

diff -puN include/linux/kexec.h~kexec-panic include/linux/kexec.h
@@ -52,5 +52,6 @@ extern asmlinkage long sys_kexec(unsigne
 	struct kexec_segment *segments);
 extern struct page *kimage_alloc_control_pages(struct kimage *image, unsigned int order);
 extern struct kimage *kexec_image;
+extern struct kimage *kexec_crash_image;
 #endif
 #endif /* LINUX_KEXEC_H */

diff -puN kernel/kexec.c~kexec-panic kernel/kexec.c
@@ -585,6 +585,7 @@ static int kimage_load_segment(struct ki
  * that to happen you need to do that yourself.
  */
 struct kimage *kexec_image = NULL;
+struct kimage *kexec_crash_image = NULL;
 
 asmlinkage long sys_kexec_load(unsigned long entry, unsigned long nr_segments,
 	struct kexec_segment *segments, unsigned long flags)

@@ -596,13 +597,6 @@ asmlinkage long sys_kexec_load(unsigned 
 	if (!capable(CAP_SYS_BOOT))
 		return -EPERM;
 
-	/*
-	 * In case we need just a little bit of special behavior for
-	 * reboot on panic.
-	 */
-	if (flags != 0)
-		return -EINVAL;
-
 	if (nr_segments > KEXEC_SEGMENT_MAX)
 		return -EINVAL;
 

@@ -632,7 +626,10 @@ asmlinkage long sys_kexec_load(unsigned 
 		}
 	}
 
-	image = xchg(&kexec_image, image);
+	if (!flags)
+		image = xchg(&kexec_image, image);
+	else
+		image = xchg(&kexec_crash_image, image);
 
  out:
 	kimage_free(image);

diff -puN include/linux/crash_dump.h~kd-misc-changes include/linux/crash_dump.h
@@ -15,15 +15,20 @@ extern void elf_kcore_store_hdr(char *, 
 #ifdef CONFIG_CRASH_DUMP
 extern ssize_t copy_oldmem_page(unsigned long, char *, size_t, int);
 extern void __crash_machine_kexec(void);
-extern void crash_enable_by_proc(void);
-extern void crash_create_proc_entry(void);
 extern int crash_dump_on;
 static inline void crash_machine_kexec(void)
 {
 	 __crash_machine_kexec();
 }
 #else
+#define crash_machine_kexec()	do { } while(0)
+#endif
+
+
+#if defined(CONFIG_CRASH_DUMP) && defined(CONFIG_PROC_FS)
+extern void crash_enable_by_proc(void);
+extern void crash_create_proc_entry(void);
+#else
 #define crash_enable_by_proc() do { } while(0)
 #define crash_create_proc_entry() do { } while(0)
-#define crash_machine_kexec()	do { } while(0)
 #endif

diff -puN kernel/crash.c~kd-misc-changes kernel/crash.c
@@ -16,6 +16,7 @@
 #include <asm/io.h>
 #include <asm/uaccess.h>
 
+#ifdef CONFIG_PROC_FS
 /*
  * Enable kexec reboot upon panic; for dumping
  */

@@ -57,6 +58,8 @@ void crash_create_proc_entry(void)
 	}
 }
 
+#endif /* CONFIG_PROC_FS */
+
 void __crash_machine_kexec(void)
 {
 	struct kimage *image;

@@ -64,7 +67,7 @@ void __crash_machine_kexec(void)
 	if ((!crash_dump_on) || (crashed))
 		return;
 
-	image = xchg(&kexec_image, 0);
+	image = xchg(&kexec_crash_image, 0);
 	if (image) {
 		crashed = 1;
 		printk(KERN_EMERG "kexec: opening parachute\n");

diff -puN arch/i386/kernel/machine_kexec.c~kd-cleanup arch/i386/kernel/machine_kexec.c
@@ -195,9 +195,6 @@ void machine_kexec(struct kimage *image)
 	unsigned long reboot_code_buffer;
 	relocate_new_kernel_t rnk;
 
-	crash_dump_stop_cpus();
-	crash_dump_save_registers();
-
 	/* Interrupts aren't acceptable while we reboot */
 	local_irq_disable();
 

@@ -208,13 +205,6 @@ void machine_kexec(struct kimage *image)
 	/* Set up an identity mapping for the reboot_code_buffer */
 	identity_map_page(reboot_code_buffer);
 
-	/*
-	 * If we are here to do a crash dump, save the memory from
-	 * 0-640k before we copy over the kexec kernel image.  Otherwise
-	 * our dump will show the wrong kernel entirely.
-	 */
-	crash_relocate_mem();
-
 	/* copy it out */
 	memcpy((void *)reboot_code_buffer, relocate_new_kernel, relocate_new_kernel_size);
 

diff -puN kernel/crash.c~kd-cleanup kernel/crash.c
@@ -71,6 +71,15 @@ void __crash_machine_kexec(void)
 	if (image) {
 		crashed = 1;
 		printk(KERN_EMERG "kexec: opening parachute\n");
+		crash_dump_stop_cpus();
+		crash_dump_save_registers();
+
+         /* If we are here to do a crash dump, save the memory from
+          * 0-640k before we copy over the kexec kernel image.  Otherwise
+          * our dump will show the wrong kernel entirely.
+          */
+        	crash_relocate_mem();
+
 		machine_kexec(image);
 	} else {
 		printk(KERN_EMERG "kexec: No kernel image loaded!\n");