Commit 23d5b73f authored by Arvind Sankar's avatar Arvind Sankar Committed by Ard Biesheuvel
Browse files

efi/libstub: Implement printk-style logging 



Use the efi_printk function in efi_info/efi_err, and add efi_debug. This
allows formatted output at different log levels.

Add the notion of a loglevel instead of just quiet/not-quiet, and
parse the efi=debug kernel parameter in addition to quiet.

Signed-off-by: default avatarArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200520170223.GA3333632@rani.riverdale.lan/


Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
parent 8fb331e1

drivers/firmware/efi/libstub/efi-stub-helper.c

+27 −2
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 


#include <linux/efi.h>

#include <linux/kernel.h>

#include <linux/printk.h> /* For CONSOLE_LOGLEVEL_* */

#include <asm/efi.h>



#include "efistub.h"
@@ -18,7 +19,7 @@ 
bool efi_nochunk;

bool efi_nokaslr;

bool efi_noinitrd;

bool efi_quiet;

int efi_loglevel = CONSOLE_LOGLEVEL_DEFAULT;

bool efi_novamap;



static bool efi_nosoftreserve;
@@ -58,6 +59,28 @@ int efi_printk(const char *fmt, ...) 
	char printf_buf[256];

	va_list args;

	int printed;

	int loglevel = printk_get_level(fmt);



	switch (loglevel) {

	case '0' ... '9':

		loglevel -= '0';

		break;

	default:

		/*

		 * Use loglevel -1 for cases where we just want to print to

		 * the screen.

		 */

		loglevel = -1;

		break;

	}



	if (loglevel >= efi_loglevel)

		return 0;



	if (loglevel >= 0)

		efi_puts("EFI stub: ");



	fmt = printk_skip_level(fmt);



	va_start(args, fmt);

	printed = vsnprintf(printf_buf, sizeof(printf_buf), fmt, args);
@@ -100,7 +123,7 @@ efi_status_t efi_parse_options(char const *cmdline) 
		if (!strcmp(param, "nokaslr")) {

			efi_nokaslr = true;

		} else if (!strcmp(param, "quiet")) {

			efi_quiet = true;

			efi_loglevel = CONSOLE_LOGLEVEL_QUIET;

		} else if (!strcmp(param, "noinitrd")) {

			efi_noinitrd = true;

		} else if (!strcmp(param, "efi") && val) {
@@ -114,6 +137,8 @@ efi_status_t efi_parse_options(char const *cmdline) 
				efi_disable_pci_dma = true;

			if (parse_option_str(val, "no_disable_early_pci_dma"))

				efi_disable_pci_dma = false;

			if (parse_option_str(val, "debug"))

				efi_loglevel = CONSOLE_LOGLEVEL_DEBUG;

		} else if (!strcmp(param, "video") &&

			   val && strstarts(val, "efifb:")) {

			efi_parse_option_graphics(val + strlen("efifb:"));

drivers/firmware/efi/libstub/efistub.h

+8 −6
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ 
#include <linux/compiler.h>

#include <linux/efi.h>

#include <linux/kernel.h>

#include <linux/kern_levels.h>

#include <linux/types.h>

#include <asm/efi.h>
@@ -34,7 +35,7 @@ 
extern bool efi_nochunk;

extern bool efi_nokaslr;

extern bool efi_noinitrd;

extern bool efi_quiet;

extern int efi_loglevel;

extern bool efi_novamap;



extern const efi_system_table_t *efi_system_table;
@@ -49,11 +50,12 @@ extern const efi_system_table_t *efi_system_table; 


#endif



#define efi_info(msg)		do {			\

	if (!efi_quiet) efi_puts("EFI stub: "msg);	\

} while (0)



#define efi_err(msg) efi_puts("EFI stub: ERROR: "msg)

#define efi_info(fmt, ...) \

	efi_printk(KERN_INFO fmt, ##__VA_ARGS__)

#define efi_err(fmt, ...) \

	efi_printk(KERN_ERR "ERROR: " fmt, ##__VA_ARGS__)

#define efi_debug(fmt, ...) \

	efi_printk(KERN_DEBUG "DEBUG: " fmt, ##__VA_ARGS__)



/* Helper macros for the usual case of using simple C variables: */

#ifndef fdt_setprop_inplace_var

CRA Git | Maintained and supported by SUSTech CRA and CCSE