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Revision d26d45253b78ec0a67003eea25bd08fceaa5b78c authored by Linus Torvalds on 22 January 2013, 18:30:49 UTC, committed by Linus Torvalds on 22 January 2013, 18:30:49 UTC 
Merge tag 'trace-3.8-rc4-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
 
Pull ftrace fix from Steven Rostedt:
 "Kprobes now uses the function tracer if it can.  That is, if a probe
  is placed on a function mcount/nop location, and the arch supports it,
  instead of adding a breakpoint, kprobes will register a function
  callback as that is much more efficient.

  The function tracer requires to update modules before they run, and
  uses the module notifier to do so.  But if something else in the
  module notifiers registers a kprobe at one of these locations, before
  ftrace can get to it, then the system could fail.

  The function tracer must be initialized early, otherwise module
  notifiers that probe will only work by chance."

* tag 'trace-3.8-rc4-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Be first to run code modification on modules
2 parent s 0944c0a + c1bf08a
Raw File
crash_dump.c 
#include <linux/kernel.h>
#include <linux/crash_dump.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/export.h>

/*
 * If we have booted due to a crash, max_pfn will be a very low value. We need
 * to know the amount of memory that the previous kernel used.
 */
unsigned long saved_max_pfn;

/*
 * stores the physical address of elf header of crash image
 *
 * Note: elfcorehdr_addr is not just limited to vmcore. It is also used by
 * is_kdump_kernel() to determine if we are booting after a panic. Hence put
 * it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE.
 */
unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;

/*
 * stores the size of elf header of crash image
 */
unsigned long long elfcorehdr_size;

/*
 * elfcorehdr= specifies the location of elf core header stored by the crashed
 * kernel. This option will be passed by kexec loader to the capture kernel.
 *
 * Syntax: elfcorehdr=[size[KMG]@]offset[KMG]
 */
static int __init setup_elfcorehdr(char *arg)
{
	char *end;
	if (!arg)
		return -EINVAL;
	elfcorehdr_addr = memparse(arg, &end);
	if (*end == '@') {
		elfcorehdr_size = elfcorehdr_addr;
		elfcorehdr_addr = memparse(end + 1, &end);
	}
	return end > arg ? 0 : -EINVAL;
}
early_param("elfcorehdr", setup_elfcorehdr);
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