Currently in arm64, FDT is mapped to RO before it's passed to early_init_dt_scan(). However, there might be some code that needs to modify FDT during init. Map FDT to RW until unflatten DT.
Signed-off-by: Hsin-Yi Wang <[email protected]> --- arch/arm64/kernel/setup.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 413d566405d1..08b22c1e72a9 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -179,9 +179,13 @@ static void __init smp_build_mpidr_hash(void) pr_warn("Large number of MPIDR hash buckets detected\n"); } +extern void *__init __fixmap_remap_fdt(phys_addr_t dt_phys, int *size, + pgprot_t prot); + static void __init setup_machine_fdt(phys_addr_t dt_phys) { - void *dt_virt = fixmap_remap_fdt(dt_phys); + int size; + void *dt_virt = __fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL); const char *name; if (!dt_virt || !early_init_dt_scan(dt_virt)) { @@ -320,6 +324,9 @@ void __init setup_arch(char **cmdline_p) /* Parse the ACPI tables for possible boot-time configuration */ acpi_boot_table_init(); + /* remap fdt to RO */ + fixmap_remap_fdt(__fdt_pointer); + if (acpi_disabled) unflatten_device_tree(); -- 2.20.1
