Commit dc63a086 authored by Jason A. Donenfeld's avatar Jason A. Donenfeld Committed by Geert Uytterhoeven
Browse files

m68k: Rework BI_VIRT_RNG_SEED as BI_RNG_SEED 



This is useful on !virt platforms for kexec, so change things from
BI_VIRT_RNG_SEED to be BI_RNG_SEED, and simply remove BI_VIRT_RNG_SEED
because it only ever lasted one release, and nothing is broken by not
having it. At the same time, keep a comment noting that it's been
removed, so that ID isn't reused. In addition, we previously documented
2-byte alignment, but 4-byte alignment is actually necessary, so update
that comment.

Suggested-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Fixes: a1ee38ab ("m68k: virt: Use RNG seed from bootinfo block")
Signed-off-by: default avatarJason A. Donenfeld <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20220927130835.1629806-2-Jason@zx2c4.com


Signed-off-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
parent 7c236d93

arch/m68k/include/uapi/asm/bootinfo-virt.h

+2 −7
Original line number Diff line number Diff line
@@ -13,13 +13,8 @@ 
#define BI_VIRT_VIRTIO_BASE	0x8004

#define BI_VIRT_CTRL_BASE	0x8005



/*

 * A random seed used to initialize the RNG. Record format:

 *

 *   - length       [ 2 bytes, 16-bit big endian ]

 *   - seed data    [ `length` bytes, padded to preserve 2-byte alignment ]

 */

#define BI_VIRT_RNG_SEED	0x8006

/* No longer used -- replaced with BI_RNG_SEED -- but don't reuse this index:

 * #define BI_VIRT_RNG_SEED	0x8006 */



#define VIRT_BOOTI_VERSION	MK_BI_VERSION(2, 0)

arch/m68k/include/uapi/asm/bootinfo.h

+7 −0
Original line number Diff line number Diff line
@@ -64,6 +64,13 @@ struct mem_info { 
					/* (struct mem_info) */

#define BI_COMMAND_LINE		0x0007	/* kernel command line parameters */

					/* (string) */

/*

 * A random seed used to initialize the RNG. Record format:

 *

 *   - length       [ 2 bytes, 16-bit big endian ]

 *   - seed data    [ `length` bytes, padded to preserve 4-byte struct alignment ]

 */

#define BI_RNG_SEED		0x0008





    /*

arch/m68k/kernel/setup_mm.c

+12 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include <linux/module.h>

#include <linux/nvram.h>

#include <linux/initrd.h>

#include <linux/random.h>



#include <asm/bootinfo.h>

#include <asm/byteorder.h>
@@ -151,6 +152,17 @@ static void __init m68k_parse_bootinfo(const struct bi_record *record) 
				sizeof(m68k_command_line));

			break;



		case BI_RNG_SEED: {

			u16 len = be16_to_cpup(data);

			add_bootloader_randomness(data + 2, len);

			/*

			 * Zero the data to preserve forward secrecy, and zero the

			 * length to prevent kexec from using it.

			 */

			memzero_explicit((void *)data, len + 2);

			break;

		}



		default:

			if (MACH_IS_AMIGA)

				unknown = amiga_parse_bootinfo(record);

arch/m68k/virt/config.c

+0 −11
Original line number Diff line number Diff line
@@ -2,7 +2,6 @@ 


#include <linux/reboot.h>

#include <linux/serial_core.h>

#include <linux/random.h>

#include <clocksource/timer-goldfish.h>



#include <asm/bootinfo.h>
@@ -93,16 +92,6 @@ int __init virt_parse_bootinfo(const struct bi_record *record) 
		data += 4;

		virt_bi_data.virtio.irq = be32_to_cpup(data);

		break;

	case BI_VIRT_RNG_SEED: {

		u16 len = be16_to_cpup(data);

		add_bootloader_randomness(data + 2, len);

		/*

		 * Zero the data to preserve forward secrecy, and zero the

		 * length to prevent kexec from using it.

		 */

		memzero_explicit((void *)data, len + 2);

		break;

	}

	default:

		unknown = 1;

		break;