From a004393f45d9a55e55d76f252914bdddffdde204 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 24 Jun 2022 17:06:45 +0200 Subject: [PATCH] arm64: idreg-override: use early FDT mapping in ID map Instead of calling into the kernel to map the FDT into the kernel page tables before even calling start_kernel(), let's switch to the initial, temporary mapping of the device tree that has been added to the ID map. Signed-off-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20220624150651.1358849-16-ardb@kernel.org Signed-off-by: Will Deacon --- arch/arm64/kernel/head.S | 1 + arch/arm64/kernel/idreg-override.c | 17 ++++++----------- 2 files changed, 7 insertions(+), 11 deletions(-) diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 8283ff848328..64ebff634b83 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -472,6 +472,7 @@ SYM_FUNC_START_LOCAL(__primary_switched) #endif mov x0, x21 // pass FDT address in x0 bl early_fdt_map // Try mapping the FDT early + mov x0, x22 // pass FDT address in x0 bl init_feature_override // Parse cpu feature overrides #ifdef CONFIG_RANDOMIZE_BASE tst x23, ~(MIN_KIMG_ALIGN - 1) // already running randomized? diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c index 8a2ceb591686..f92836e196e5 100644 --- a/arch/arm64/kernel/idreg-override.c +++ b/arch/arm64/kernel/idreg-override.c @@ -201,16 +201,11 @@ static __init void __parse_cmdline(const char *cmdline, bool parse_aliases) } while (1); } -static __init const u8 *get_bootargs_cmdline(void) +static __init const u8 *get_bootargs_cmdline(const void *fdt) { const u8 *prop; - void *fdt; int node; - fdt = get_early_fdt_ptr(); - if (!fdt) - return NULL; - node = fdt_path_offset(fdt, "/chosen"); if (node < 0) return NULL; @@ -222,9 +217,9 @@ static __init const u8 *get_bootargs_cmdline(void) return strlen(prop) ? prop : NULL; } -static __init void parse_cmdline(void) +static __init void parse_cmdline(const void *fdt) { - const u8 *prop = get_bootargs_cmdline(); + const u8 *prop = get_bootargs_cmdline(fdt); if (IS_ENABLED(CONFIG_CMDLINE_FORCE) || !prop) __parse_cmdline(CONFIG_CMDLINE, true); @@ -234,9 +229,9 @@ static __init void parse_cmdline(void) } /* Keep checkers quiet */ -void init_feature_override(void); +void init_feature_override(const void *fdt); -asmlinkage void __init init_feature_override(void) +asmlinkage void __init init_feature_override(const void *fdt) { int i; @@ -247,7 +242,7 @@ asmlinkage void __init init_feature_override(void) } } - parse_cmdline(); + parse_cmdline(fdt); for (i = 0; i < ARRAY_SIZE(regs); i++) { if (regs[i]->override)