We will be moving the call to kaslr_init() into setup_arch() in an
upcoming patch, and this needs the FDT to be writable so the KASLR seed
can be wiped from it.
So break out the R/O remapping of the FDT from setup_machine_fdt() and
call it explicitly from setup_arch().
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
arch/arm64/kernel/setup.c | 6 +++---
arch/arm64/mm/mmu.c | 12 +++++++-----
2 files changed, 10 insertions(+), 8 deletions(-)
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 3505789cf4bd..ebf69312eabf 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -203,9 +203,6 @@ static void __init setup_machine_fdt(phys_addr_t dt_phys)
cpu_relax();
}
- /* Early fixups are done, map the FDT as read-only now */
- fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL_RO);
-
name = of_flat_dt_get_machine_name();
if (!name)
return;
@@ -316,6 +313,9 @@ void __init __no_sanitize_address setup_arch(char **cmdline_p)
setup_machine_fdt(__fdt_pointer);
+ /* Early fixups are done, map the FDT as read-only now */
+ fixmap_remap_fdt(__fdt_pointer, NULL, PAGE_KERNEL_RO);
+
/*
* Initialise the static keys early as they may be enabled by the
* cpufeature code and early parameters.
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index e74a6453cb14..20dd95a750bc 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1324,7 +1324,7 @@ void __set_fixmap(enum fixed_addresses idx,
void *__init fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
{
const u64 dt_virt_base = __fix_to_virt(FIX_FDT);
- int offset;
+ int offset, dt_size;
void *dt_virt;
/*
@@ -1363,13 +1363,15 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
if (fdt_magic(dt_virt) != FDT_MAGIC)
return NULL;
- *size = fdt_totalsize(dt_virt);
- if (*size > MAX_FDT_SIZE)
+ dt_size = fdt_totalsize(dt_virt);
+ if (size)
+ *size = dt_size;
+ if (dt_size > MAX_FDT_SIZE)
return NULL;
- if (offset + *size > SWAPPER_BLOCK_SIZE)
+ if (offset + dt_size > SWAPPER_BLOCK_SIZE)
create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE), dt_virt_base,
- round_up(offset + *size, SWAPPER_BLOCK_SIZE), prot);
+ round_up(offset + dt_size, SWAPPER_BLOCK_SIZE), prot);
return dt_virt;
}
--
2.30.2
