github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-06-07 14:04:54 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

FROMGIT: arm64: Extract early FDT mapping from kaslr_early_init()

Browse Source 
As we want to parse more options very early in the kernel lifetime,
let's always map the FDT early. This is achieved by moving that
code out of kaslr_early_init().

No functional change expected.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: David Brazdil <dbrazdil@google.com>
Link: https://lore.kernel.org/r/20210208095732.3267263-13-maz@kernel.org
[will: Ensue KASAN is enabled before running C code]
Signed-off-by: Will Deacon <will@kernel.org>
(cherry picked from commit f6f0c4362f
 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-next/cpufeature)
Signed-off-by: Will Deacon <willdeacon@google.com>
Bug: 175544340
Change-Id: Ie8795399948d170975a1070facce16defca0cb39
This commit is contained in:
Marc Zyngier 2021-02-08 09:57:21 +00:00 committed by Will Deacon
parent a31f6cf381
commit c89aee1e3d
4 changed files with 31 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
arch/arm64/include/asm/setup.h Normal file
View File

@ -0,0 +1,11 @@
// SPDX-License-Identifier: GPL-2.0
#ifndef __ARM64_ASM_SETUP_H
#define __ARM64_ASM_SETUP_H
#include <uapi/asm/setup.h>
void *get_early_fdt_ptr(void);
void early_fdt_map(u64 dt_phys);
#endif

3
arch/arm64/kernel/head.S
View File

@ -451,10 +451,11 @@ SYM_FUNC_START_LOCAL(__primary_switched)
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
bl kasan_early_init
#endif
mov x0, x21 // pass FDT address in x0
bl early_fdt_map // Try mapping the FDT early
#ifdef CONFIG_RANDOMIZE_BASE
tst x23, ~(MIN_KIMG_ALIGN - 1) // already running randomized?
b.ne 0f
mov x0, x21 // pass FDT address in x0
bl kaslr_early_init // parse FDT for KASLR options
cbz x0, 0f // KASLR disabled? just proceed
orr x23, x23, x0 // record KASLR offset

7
arch/arm64/kernel/kaslr.c
View File

@ -19,6 +19,7 @@
#include <asm/memory.h>
#include <asm/mmu.h>
#include <asm/sections.h>
#include <asm/setup.h>
enum kaslr_status {
KASLR_ENABLED,
@ -92,12 +93,11 @@ static __init bool is_kaslr_disabled_cmdline(void *fdt)
* containing function pointers) to be reinitialized, and zero-initialized
* .bss variables will be reset to 0.
*/
u64 __init kaslr_early_init(u64 dt_phys)
u64 __init kaslr_early_init(void)
{
void *fdt;
u64 seed, offset, mask, module_range;
unsigned long raw;
int size;
/*
* Set a reasonable default for module_alloc_base in case
@ -111,8 +111,7 @@ u64 __init kaslr_early_init(u64 dt_phys)
* and proceed with KASLR disabled. We will make another
* attempt at mapping the FDT in setup_machine()
*/
early_fixmap_init();
fdt = fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL);
fdt = get_early_fdt_ptr();
if (!fdt) {
kaslr_status = KASLR_DISABLED_FDT_REMAP;
return 0;

15
arch/arm64/kernel/setup.c
View File

@ -168,6 +168,21 @@ static void __init smp_build_mpidr_hash(void)
pr_warn("Large number of MPIDR hash buckets detected\n");
}
static void *early_fdt_ptr __initdata;
void __init *get_early_fdt_ptr(void)
{
return early_fdt_ptr;
}
asmlinkage void __init early_fdt_map(u64 dt_phys)
{
int fdt_size;
early_fixmap_init();
early_fdt_ptr = fixmap_remap_fdt(dt_phys, &fdt_size, PAGE_KERNEL);
}
static void __init setup_machine_fdt(phys_addr_t dt_phys)
{
int size;