Commit b2a992a5 authored by Vasily Gorbik's avatar Vasily Gorbik Committed by Alexander Gordeev
Browse files

s390/boot: Dump message ring buffer on crash with bootdebug 



Dump the boot message ring buffer when a crash occurs during boot, but
only if bootdebug is enabled. This helps assist in analyzing boot-time
issues by providing additional debugging information.

Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
Acked-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
parent b79015ae

arch/s390/boot/boot.h

+1 −0
Original line number Diff line number Diff line
@@ -76,6 +76,7 @@ int __printf(1, 2) boot_printk(const char *fmt, ...); 
void print_stacktrace(unsigned long sp);

void error(char *m);

int get_random(unsigned long limit, unsigned long *value);

void boot_rb_dump(void);



#ifndef boot_fmt

#define boot_fmt(fmt)	fmt

arch/s390/boot/pgm_check_info.c

+2 −0
Original line number Diff line number Diff line
@@ -37,6 +37,8 @@ void print_pgm_check_info(void) 
	unsigned long *gpregs = (unsigned long *)get_lowcore()->gpregs_save_area;

	struct psw_bits *psw = &psw_bits(get_lowcore()->psw_save_area);



	if (bootdebug)

		boot_rb_dump();

	boot_emerg("Linux version %s\n", kernel_version);

	if (!is_prot_virt_guest() && early_command_line[0])

		boot_emerg("Kernel command line: %s\n", early_command_line);

arch/s390/boot/printk.c

+18 −0
Original line number Diff line number Diff line
@@ -32,6 +32,24 @@ static void boot_rb_add(const char *str, size_t len) 
	boot_rb_off += len + 1;

}



static void print_rb_entry(const char *str)

{

	sclp_early_printk(printk_skip_level(str));

}



static bool debug_messages_printed(void)

{

	return boot_earlyprintk && (boot_ignore_loglevel || boot_console_loglevel > LOGLEVEL_DEBUG);

}



void boot_rb_dump(void)

{

	if (debug_messages_printed())

		return;

	sclp_early_printk("Boot messages ring buffer:\n");

	boot_rb_foreach(print_rb_entry);

}



const char hex_asc[] = "0123456789abcdef";



static char *as_hex(char *dst, unsigned long val, int pad)