From f6f0c4362f070cab4a0cec432e82428d702ce0a6 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 8 Feb 2021 09:57:21 +0000 Subject: arm64: Extract early FDT mapping from kaslr_early_init() 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 Acked-by: Catalin Marinas Acked-by: David Brazdil 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 --- arch/arm64/include/asm/setup.h | 11 +++++++++++ arch/arm64/kernel/head.S | 3 ++- arch/arm64/kernel/kaslr.c | 7 +++---- arch/arm64/kernel/setup.c | 15 +++++++++++++++ 4 files changed, 31 insertions(+), 5 deletions(-) create mode 100644 arch/arm64/include/asm/setup.h (limited to 'arch') diff --git a/arch/arm64/include/asm/setup.h b/arch/arm64/include/asm/setup.h new file mode 100644 index 000000000000..d3320618ed14 --- /dev/null +++ b/arch/arm64/include/asm/setup.h @@ -0,0 +1,11 @@ +// SPDX-License-Identifier: GPL-2.0 + +#ifndef __ARM64_ASM_SETUP_H +#define __ARM64_ASM_SETUP_H + +#include + +void *get_early_fdt_ptr(void); +void early_fdt_map(u64 dt_phys); + +#endif diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 2c1b8ffa3d3e..070d1c6ec9eb 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -436,10 +436,11 @@ 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 diff --git a/arch/arm64/kernel/kaslr.c b/arch/arm64/kernel/kaslr.c index 1c74c45b9494..5fc86e7d01a1 100644 --- a/arch/arm64/kernel/kaslr.c +++ b/arch/arm64/kernel/kaslr.c @@ -19,6 +19,7 @@ #include #include #include +#include enum kaslr_status { KASLR_ENABLED, @@ -92,12 +93,11 @@ out: * 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; diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index c18aacde8bb0..61845c0821d9 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -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; -- cgit v1.2.3