threeeye
bc1d038eac
Squashed backup commit (no shallow-clone history issues) of xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2 branch, upstream commit 9eece662e) plus all fixes applied to get everpal_defconfig building clean against a modern (GCC 15.2.0) toolchain -- see the previous commit message on the lineage-23.2 branch (also in this repo history is not available here since this is a squashed snapshot; full incremental history lives in the local DL380 checkout and the upstream GitHub remote). Upstream: https://github.com/xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2)
73 lines
1.7 KiB
C
73 lines
1.7 KiB
C
/*
|
|
* purgatory: Runs between two kernels
|
|
*
|
|
* Copyright (C) 2014 Red Hat Inc.
|
|
*
|
|
* Author:
|
|
* Vivek Goyal <vgoyal@redhat.com>
|
|
*
|
|
* This source code is licensed under the GNU General Public License,
|
|
* Version 2. See the file COPYING for more details.
|
|
*/
|
|
|
|
#include <linux/bug.h>
|
|
#include <asm/purgatory.h>
|
|
|
|
#include "sha256.h"
|
|
#include "../boot/string.h"
|
|
|
|
unsigned long purgatory_backup_dest __section(.kexec-purgatory);
|
|
unsigned long purgatory_backup_src __section(.kexec-purgatory);
|
|
unsigned long purgatory_backup_sz __section(.kexec-purgatory);
|
|
|
|
u8 purgatory_sha256_digest[SHA256_DIGEST_SIZE] __section(.kexec-purgatory);
|
|
|
|
struct kexec_sha_region purgatory_sha_regions[KEXEC_SEGMENT_MAX] __section(.kexec-purgatory);
|
|
|
|
/*
|
|
* On x86, second kernel requries first 640K of memory to boot. Copy
|
|
* first 640K to a backup region in reserved memory range so that second
|
|
* kernel can use first 640K.
|
|
*/
|
|
static int copy_backup_region(void)
|
|
{
|
|
if (purgatory_backup_dest) {
|
|
memcpy((void *)purgatory_backup_dest,
|
|
(void *)purgatory_backup_src, purgatory_backup_sz);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int verify_sha256_digest(void)
|
|
{
|
|
struct kexec_sha_region *ptr, *end;
|
|
u8 digest[SHA256_DIGEST_SIZE];
|
|
struct sha256_state sctx;
|
|
|
|
sha256_init(&sctx);
|
|
end = purgatory_sha_regions + ARRAY_SIZE(purgatory_sha_regions);
|
|
|
|
for (ptr = purgatory_sha_regions; ptr < end; ptr++)
|
|
sha256_update(&sctx, (uint8_t *)(ptr->start), ptr->len);
|
|
|
|
sha256_final(&sctx, digest);
|
|
|
|
if (memcmp(digest, purgatory_sha256_digest, sizeof(digest)))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void purgatory(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = verify_sha256_digest();
|
|
if (ret) {
|
|
/* loop forever */
|
|
for (;;)
|
|
;
|
|
}
|
|
copy_backup_region();
|
|
}
|