@@ -264,6 +264,14 @@ arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section,
return -ENOEXEC;
}
#endif
+
+extern bool kexec_file_dbg_print;
+
+#define kexec_dprintk(fmt, ...) \
+ printk("%s" fmt, \
+ kexec_file_dbg_print ? KERN_INFO : KERN_DEBUG, \
+ ##__VA_ARGS__)
+
#endif /* CONFIG_KEXEC_FILE */
#ifdef CONFIG_KEXEC_ELF
@@ -403,7 +411,7 @@ bool kexec_load_permitted(int kexec_image_type);
/* List of defined/legal kexec file flags */
#define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
- KEXEC_FILE_NO_INITRAMFS)
+ KEXEC_FILE_NO_INITRAMFS | KEXEC_FILE_DEBUG)
/* flag to track if kexec reboot is in progress */
extern bool kexec_in_progress;
@@ -25,6 +25,7 @@
#define KEXEC_FILE_UNLOAD 0x00000001
#define KEXEC_FILE_ON_CRASH 0x00000002
#define KEXEC_FILE_NO_INITRAMFS 0x00000004
+#define KEXEC_FILE_DEBUG 0x00000008
/* These values match the ELF architecture values.
* Unless there is a good reason that should continue to be the case.
@@ -38,6 +38,8 @@ void set_kexec_sig_enforced(void)
}
#endif
+bool kexec_file_dbg_print;
+
static int kexec_calculate_store_digests(struct kimage *image);
/* Maximum size in bytes for kernel/initrd files. */
@@ -123,6 +125,8 @@ void kimage_file_post_load_cleanup(struct kimage *image)
*/
kfree(image->image_loader_data);
image->image_loader_data = NULL;
+
+ kexec_file_dbg_print = false;
}
#ifdef CONFIG_KEXEC_SIG
@@ -278,6 +282,7 @@ kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
if (!image)
return -ENOMEM;
+ kexec_file_dbg_print = !!(flags & KEXEC_FILE_DEBUG);
image->file_mode = 1;
if (kexec_on_panic) {
When specifying 'kexec -c -d', kexec_load interface will print loading information, e.g the regions where kernel/initrd/purgatory/cmdline are put, the memmap passed to 2nd kernel taken as system RAM ranges, and printing all contents of struct kexec_segment, etc. These are very helpful for analyzing or positioning what's happening when kexec/kdump itself failed. The debugging printing for kexec_load interface is made in user space utility kexec-tools. Whereas, with kexec_file_load interface, 'kexec -s -d' print nothing. Because kexec_file code is mostly implemented in kernel space, and the debugging printing functionality is missed. It's not convenient when debugging kexec/kdump loading and jumping with kexec_file_load interface. Now add KEXEC_FILE_DEBUG to kexec_file flag to control the debugging message printing. And add global variable kexec_file_dbg_print and macro kexec_dprintk() to facilitate the printing. This is a preparation, later kexec_dprintk() will be used to replace the existing pr_debug(). Once 'kexec -s -d' is specified, it will print out kexec/kdump loading information. If '-d' is not specified, it regresses to pr_debug(). Signed-off-by: Baoquan He <bhe@redhat.com> --- include/linux/kexec.h | 10 +++++++++- include/uapi/linux/kexec.h | 1 + kernel/kexec_file.c | 5 +++++ 3 files changed, 15 insertions(+), 1 deletion(-)