mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 02:30:34 +02:00 
			
		
		
		
	In kdump kernel, /proc/vmcore is an elf file mapping the crashed kernel's old memory content. Its elf header is constructed in 1st kernel and passed to kdump kernel via elfcorehdr_addr. Config CRASH_DUMP enables the code of 1st kernel's old memory accessing in different architectures. Currently, config FA_DUMP has dependency on CRASH_DUMP because fadump needs access global variable 'elfcorehdr_addr' to judge if it's in kdump kernel within function is_kdump_kernel(). In the current kernel/crash_dump.c, variable 'elfcorehdr_addr' is defined, and function setup_elfcorehdr() used to parse kernel parameter to fetch the passed value of elfcorehdr_addr. Only for accessing elfcorehdr_addr, FA_DUMP really doesn't have to depends on CRASH_DUMP. To remove the dependency of FA_DUMP on CRASH_DUMP to avoid confusion, rename kernel/crash_dump.c to kernel/elfcorehdr.c, and build it when CONFIG_VMCORE_INFO is ebabled. With this, FA_DUMP doesn't need to depend on CRASH_DUMP. [bhe@redhat.com: power/fadump: make FA_DUMP select CRASH_DUMP] Link: https://lkml.kernel.org/r/Zb8D1ASrgX0qVm9z@MiWiFi-R3L-srv Link: https://lkml.kernel.org/r/20240124051254.67105-4-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Hari Bathini <hbathini@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Pingfan Liu <piliu@redhat.com> Cc: Klara Modin <klarasmodin@gmail.com> Cc: Michael Kelley <mhklinux@outlook.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
		
			
				
	
	
		
			41 lines
		
	
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			41 lines
		
	
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* SPDX-License-Identifier: GPL-2.0 */
 | 
						|
#ifndef LINUX_KEXEC_INTERNAL_H
 | 
						|
#define LINUX_KEXEC_INTERNAL_H
 | 
						|
 | 
						|
#include <linux/kexec.h>
 | 
						|
 | 
						|
struct kexec_segment;
 | 
						|
 | 
						|
struct kimage *do_kimage_alloc_init(void);
 | 
						|
int sanity_check_segment_list(struct kimage *image);
 | 
						|
void kimage_free_page_list(struct list_head *list);
 | 
						|
void kimage_free(struct kimage *image);
 | 
						|
int kimage_load_segment(struct kimage *image, struct kexec_segment *segment);
 | 
						|
void kimage_terminate(struct kimage *image);
 | 
						|
int kimage_is_destination_range(struct kimage *image,
 | 
						|
				unsigned long start, unsigned long end);
 | 
						|
 | 
						|
/*
 | 
						|
 * Whatever is used to serialize accesses to the kexec_crash_image needs to be
 | 
						|
 * NMI safe, as __crash_kexec() can happen during nmi_panic(), so here we use a
 | 
						|
 * "simple" atomic variable that is acquired with a cmpxchg().
 | 
						|
 */
 | 
						|
extern atomic_t __kexec_lock;
 | 
						|
static inline bool kexec_trylock(void)
 | 
						|
{
 | 
						|
	return atomic_cmpxchg_acquire(&__kexec_lock, 0, 1) == 0;
 | 
						|
}
 | 
						|
static inline void kexec_unlock(void)
 | 
						|
{
 | 
						|
	atomic_set_release(&__kexec_lock, 0);
 | 
						|
}
 | 
						|
 | 
						|
#ifdef CONFIG_KEXEC_FILE
 | 
						|
#include <linux/purgatory.h>
 | 
						|
void kimage_file_post_load_cleanup(struct kimage *image);
 | 
						|
extern char kexec_purgatory[];
 | 
						|
extern size_t kexec_purgatory_size;
 | 
						|
#else /* CONFIG_KEXEC_FILE */
 | 
						|
static inline void kimage_file_post_load_cleanup(struct kimage *image) { }
 | 
						|
#endif /* CONFIG_KEXEC_FILE */
 | 
						|
#endif /* LINUX_KEXEC_INTERNAL_H */
 |