Commit c09f8d0a authored by Vasily Gorbik's avatar Vasily Gorbik Committed by Alexander Gordeev
Browse files

s390/boot: Defer boot messages when earlyprintk is not enabled 



When earlyprintk is not specified, boot messages are only stored in a
ring buffer to be printed later by printk when console driver is
registered.

Critical messages from boot_emerg() are always printed immediately,
even without earlyprintk.

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 847e5a4c

arch/s390/boot/ipl_parm.c

+2 −0
Original line number Diff line number Diff line
@@ -313,6 +313,8 @@ void parse_boot_command_line(void) 
#endif

		if (!strcmp(param, "relocate_lowcore") && test_facility(193))

			relocate_lowcore = 1;

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

			boot_earlyprintk = true;

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

			boot_console_loglevel = CONSOLE_LOGLEVEL_DEBUG;

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

arch/s390/boot/printk.c

+7 −2
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
#include <linux/ctype.h>

#include <asm/stacktrace.h>

#include <asm/boot_data.h>

#include <asm/sections.h>

#include <asm/lowcore.h>

#include <asm/setup.h>

#include <asm/sclp.h>
@@ -13,8 +14,9 @@ 


int boot_console_loglevel = CONFIG_CONSOLE_LOGLEVEL_DEFAULT;

bool boot_ignore_loglevel;

char boot_rb[PAGE_SIZE * 2];

size_t boot_rb_off;

char __bootdata(boot_rb)[PAGE_SIZE * 2];

bool __bootdata(boot_earlyprintk);

size_t __bootdata(boot_rb_off);



static void boot_rb_add(const char *str, size_t len)

{
@@ -163,6 +165,9 @@ static void boot_console_earlyprintk(const char *buf) 
{

	int level = printk_loglevel(buf);



	/* always print emergency messages */

	if (level > LOGLEVEL_EMERG && !boot_earlyprintk)

		return;

	if (boot_ignore_loglevel || level < boot_console_loglevel)

		sclp_early_printk(printk_skip_level(buf));

}

arch/s390/include/asm/boot_data.h

+1 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ extern unsigned long early_ipl_comp_list_addr; 
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;



#define boot_rb_foreach(cb)							\

arch/s390/kernel/setup.c

+18 −0
Original line number Diff line number Diff line
@@ -157,6 +157,10 @@ u64 __bootdata_preserved(stfle_fac_list[16]); 
EXPORT_SYMBOL(stfle_fac_list);

struct oldmem_data __bootdata_preserved(oldmem_data);



char __bootdata(boot_rb)[PAGE_SIZE * 2];

bool __bootdata(boot_earlyprintk);

size_t __bootdata(boot_rb_off);



unsigned long __bootdata_preserved(VMALLOC_START);

EXPORT_SYMBOL(VMALLOC_START);
@@ -877,6 +881,17 @@ static void __init log_component_list(void) 
	}

}



/*

 * Print avoiding interpretation of % in buf

 */

static void __init print_rb_entry(char *buf)

{

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



	fmt[1] = printk_get_level(buf);

	printk(fmt, printk_skip_level(buf));

}



/*

 * Setup function called from init/main.c just after the banner

 * was printed.
@@ -896,6 +911,9 @@ void __init setup_arch(char **cmdline_p) 
		pr_info("Linux is running natively in 64-bit mode\n");

	else

		pr_info("Linux is running as a guest in 64-bit mode\n");

	/* Print decompressor messages if not already printed */

	if (!boot_earlyprintk)

		boot_rb_foreach(print_rb_entry);



	if (have_relocated_lowcore())

		pr_info("Lowcore relocated to 0x%px\n", get_lowcore());