Commit b79015ae authored by Vasily Gorbik's avatar Vasily Gorbik Committed by Alexander Gordeev
Browse files

s390/boot: Add prefix filtering to bootdebug messages 



Enhance boot debugging by allowing the "bootdebug" kernel parameter to
accept an optional comma-separated list of prefixes. Only debug messages
starting with these prefixes will be printed during boot. For example:

    bootdebug=startup,vmem

Not specifying a filter for the "bootdebug" parameter prints all debug
messages. The `boot_fmt` macro can be defined to set a common prefix:

    #define boot_fmt(fmt) "startup: " fmt

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 d20d8e51

arch/s390/boot/boot.h

+12 −8
Original line number Diff line number Diff line
@@ -77,14 +77,18 @@ void print_stacktrace(unsigned long sp); 
void error(char *m);

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



#define boot_emerg(fmt, ...)	boot_printk(KERN_EMERG fmt, ##__VA_ARGS__)

#define boot_alert(fmt, ...)	boot_printk(KERN_ALERT fmt, ##__VA_ARGS__)

#define boot_crit(fmt, ...)	boot_printk(KERN_CRIT fmt, ##__VA_ARGS__)

#define boot_err(fmt, ...)	boot_printk(KERN_ERR fmt, ##__VA_ARGS__)

#define boot_warn(fmt, ...)	boot_printk(KERN_WARNING fmt, ##__VA_ARGS__)

#define boot_notice(fmt, ...)	boot_printk(KERN_NOTICE fmt, ##__VA_ARGS__)

#define boot_info(fmt, ...)	boot_printk(KERN_INFO fmt, ##__VA_ARGS__)

#define boot_debug(fmt, ...)	boot_printk(KERN_DEBUG fmt, ##__VA_ARGS__)

#ifndef boot_fmt

#define boot_fmt(fmt)	fmt

#endif



#define boot_emerg(fmt, ...)	boot_printk(KERN_EMERG boot_fmt(fmt), ##__VA_ARGS__)

#define boot_alert(fmt, ...)	boot_printk(KERN_ALERT boot_fmt(fmt), ##__VA_ARGS__)

#define boot_crit(fmt, ...)	boot_printk(KERN_CRIT boot_fmt(fmt), ##__VA_ARGS__)

#define boot_err(fmt, ...)	boot_printk(KERN_ERR boot_fmt(fmt), ##__VA_ARGS__)

#define boot_warn(fmt, ...)	boot_printk(KERN_WARNING boot_fmt(fmt), ##__VA_ARGS__)

#define boot_notice(fmt, ...)	boot_printk(KERN_NOTICE boot_fmt(fmt), ##__VA_ARGS__)

#define boot_info(fmt, ...)	boot_printk(KERN_INFO boot_fmt(fmt), ##__VA_ARGS__)

#define boot_debug(fmt, ...)	boot_printk(KERN_DEBUG boot_fmt(fmt), ##__VA_ARGS__)



extern struct machine_info machine;

extern int boot_console_loglevel;

arch/s390/boot/ipl_parm.c

+4 −1
Original line number Diff line number Diff line
@@ -317,8 +317,11 @@ void parse_boot_command_line(void) 
			boot_earlyprintk = true;

		if (!strcmp(param, "debug"))

			boot_console_loglevel = CONSOLE_LOGLEVEL_DEBUG;

		if (!strcmp(param, "bootdebug"))

		if (!strcmp(param, "bootdebug")) {

			bootdebug = true;

			if (val)

				strncpy(bootdebug_filter, val, sizeof(bootdebug_filter) - 1);

		}

		if (!strcmp(param, "quiet"))

			boot_console_loglevel = CONSOLE_LOGLEVEL_QUIET;

		if (!strcmp(param, "ignore_loglevel"))

arch/s390/boot/printk.c

+4 −2
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ bool boot_ignore_loglevel; 
char __bootdata(boot_rb)[PAGE_SIZE * 2];

bool __bootdata(boot_earlyprintk);

size_t __bootdata(boot_rb_off);

char __bootdata(bootdebug_filter)[128];

bool __bootdata(bootdebug);



static void boot_rb_add(const char *str, size_t len)
@@ -169,11 +170,12 @@ static void boot_console_earlyprintk(const char *buf) 
	/* always print emergency messages */

	if (level > LOGLEVEL_EMERG && !boot_earlyprintk)

		return;

	buf = printk_skip_level(buf);

	/* print debug messages only when bootdebug is enabled */

	if (level == LOGLEVEL_DEBUG && !bootdebug)

	if (level == LOGLEVEL_DEBUG && (!bootdebug || !bootdebug_filter_match(buf)))

		return;

	if (boot_ignore_loglevel || level < boot_console_loglevel)

		sclp_early_printk(printk_skip_level(buf));

		sclp_early_printk(buf);

}



#define va_arg_len_type(args, lenmod, typemod)				\

arch/s390/include/asm/boot_data.h

+25 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef _ASM_S390_BOOT_DATA_H



#include <linux/string.h>

#include <asm/setup.h>

#include <asm/ipl.h>
@@ -18,6 +19,7 @@ extern unsigned long early_ipl_comp_list_size; 
extern char boot_rb[PAGE_SIZE * 2];

extern bool boot_earlyprintk;

extern size_t boot_rb_off;

extern char bootdebug_filter[128];

extern bool bootdebug;



#define boot_rb_foreach(cb)							\
@@ -30,4 +32,27 @@ extern bool bootdebug; 
			cb(boot_rb + off);					\

	} while (0)



/*

 * bootdebug_filter is a comma separated list of strings,

 * where each string can be a prefix of the message.

 */

static inline bool bootdebug_filter_match(const char *buf)

{

	char *p = bootdebug_filter, *s;

	char *end;



	if (!*p)

		return true;



	end = p + strlen(p);

	while (p < end) {

		p = skip_spaces(p);

		s = memscan(p, ',', end - p);

		if (!strncmp(p, buf, s - p))

			return true;

		p = s + 1;

	}

	return false;

}



#endif /* _ASM_S390_BOOT_DATA_H */

arch/s390/kernel/setup.c

+5 −3
Original line number Diff line number Diff line
@@ -160,6 +160,7 @@ struct oldmem_data __bootdata_preserved(oldmem_data); 
char __bootdata(boot_rb)[PAGE_SIZE * 2];

bool __bootdata(boot_earlyprintk);

size_t __bootdata(boot_rb_off);

char __bootdata(bootdebug_filter)[128];

bool __bootdata(bootdebug);



unsigned long __bootdata_preserved(VMALLOC_START);
@@ -886,16 +887,17 @@ static void __init log_component_list(void) 
 * Print avoiding interpretation of % in buf and taking bootdebug option

 * into consideration.

 */

static void __init print_rb_entry(char *buf)

static void __init print_rb_entry(const char *buf)

{

	char fmt[] = KERN_SOH "0boot: %s";

	int level = printk_get_level(buf);



	if (level == KERN_DEBUG[1] && !bootdebug)

	buf = printk_skip_level(buf);

	if (level == KERN_DEBUG[1] && (!bootdebug || !bootdebug_filter_match(buf)))

		return;



	fmt[1] = level;

	printk(fmt, printk_skip_level(buf));

	printk(fmt, buf);

}



/*