From 1191b6256e50a07e7d8ce36eb970708e42a4be1a Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Wed, 13 Jul 2022 15:09:49 +0100 Subject: arm64: fix KASAN_INLINE Since commit: a004393f45d9a55e ("arm64: idreg-override: use early FDT mapping in ID map") Kernels built with KASAN_INLINE=y die early in boot before producing any console output. This is because the accesses made to the FDT (e.g. in generic string processing functions) are instrumented with KASAN, and with KASAN_INLINE=y any access to an address in TTBR0 results in a bogus shadow VA, resulting in a data abort. This patch fixes this by reverting commits: 7559d9f97581654f ("arm64: setup: drop early FDT pointer helpers") bd0c3fa21878b6d0 ("arm64: idreg-override: use early FDT mapping in ID map") ... and using the TTBR1 fixmap mapping of the FDT. Note that due to a later commit: b65e411d6cc2f12a ("arm64: Save state of HCR_EL2.E2H before switch to EL1") ... which altered the prototype of init_feature_override() (and invocation from head.S), commit bd0c3fa21878b6d0 does not revert cleanly, and I've fixed that up manually. Fixes: a004393f45d9 ("arm64: idreg-override: use early FDT mapping in ID map") Cc: Ard Biesheuvel Cc: Catalin Marinas Cc: Marc Zyngier Cc: Will Deacon Acked-by: Catalin Marinas Signed-off-by: Mark Rutland Link: https://lore.kernel.org/r/20220713140949.45440-1-mark.rutland@arm.com Signed-off-by: Will Deacon --- arch/arm64/kernel/head.S | 5 +++-- arch/arm64/kernel/idreg-override.c | 17 +++++++++++------ arch/arm64/kernel/setup.c | 15 +++++++++++++++ 3 files changed, 29 insertions(+), 8 deletions(-) (limited to 'arch/arm64/kernel') diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 29d641290293..cefe6a73ee54 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -456,8 +456,9 @@ SYM_FUNC_START_LOCAL(__primary_switched) #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) bl kasan_early_init #endif - mov x0, x22 // pass FDT address in x0 - mov x1, x20 // pass the full boot status + mov x0, x21 // pass FDT address in x0 + bl early_fdt_map // Try mapping the FDT early + mov x0, x20 // pass the full boot status bl init_feature_override // Parse cpu feature overrides mov x0, x20 bl finalise_el2 // Prefer VHE if possible diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c index aa2a53d0d417..7206fd0ed9eb 100644 --- a/arch/arm64/kernel/idreg-override.c +++ b/arch/arm64/kernel/idreg-override.c @@ -262,11 +262,16 @@ static __init void __parse_cmdline(const char *cmdline, bool parse_aliases) } while (1); } -static __init const u8 *get_bootargs_cmdline(const void *fdt) +static __init const u8 *get_bootargs_cmdline(void) { 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; @@ -278,9 +283,9 @@ static __init const u8 *get_bootargs_cmdline(const void *fdt) return strlen(prop) ? prop : NULL; } -static __init void parse_cmdline(const void *fdt) +static __init void parse_cmdline(void) { - const u8 *prop = get_bootargs_cmdline(fdt); + const u8 *prop = get_bootargs_cmdline(); if (IS_ENABLED(CONFIG_CMDLINE_FORCE) || !prop) __parse_cmdline(CONFIG_CMDLINE, true); @@ -290,9 +295,9 @@ static __init void parse_cmdline(const void *fdt) } /* Keep checkers quiet */ -void init_feature_override(const void *fdt, u64 boot_status); +void init_feature_override(u64 boot_status); -asmlinkage void __init init_feature_override(const void *fdt, u64 boot_status) +asmlinkage void __init init_feature_override(u64 boot_status) { int i; @@ -305,7 +310,7 @@ asmlinkage void __init init_feature_override(const void *fdt, u64 boot_status) __boot_status = boot_status; - parse_cmdline(fdt); + parse_cmdline(); for (i = 0; i < ARRAY_SIZE(regs); i++) { if (regs[i]->override) diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index d0e6c7a291da..fea3223704b6 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -163,6 +163,21 @@ 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