arm64: map FDT as RW for early_init_dt_scan()

Currently in arm64, FDT is mapped to RO before it's passed to
early_init_dt_scan(). However, there might be some codes
(eg. commit "fdt: add support for rng-seed") that need to modify FDT
during init. Map FDT to RO after early fixups are done.

Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Hsin-Yi Wang 2019-08-23 14:24:50 +08:00 committed by Will Deacon
parent e21a712a96
commit e112b032a7
4 changed files with 11 additions and 20 deletions

View File

@ -126,7 +126,7 @@ extern void init_mem_pgprot(void);
extern void create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys,
unsigned long virt, phys_addr_t size,
pgprot_t prot, bool page_mappings_only);
extern void *fixmap_remap_fdt(phys_addr_t dt_phys);
extern void *fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot);
extern void mark_linear_text_alias_ro(void);
#define INIT_MM_CONTEXT(name) \

View File

@ -62,9 +62,6 @@ static __init const u8 *kaslr_get_cmdline(void *fdt)
return default_cmdline;
}
extern void *__init __fixmap_remap_fdt(phys_addr_t dt_phys, int *size,
pgprot_t prot);
/*
* This routine will be executed with the kernel mapped at its default virtual
* address, and if it returns successfully, the kernel will be remapped, and
@ -93,7 +90,7 @@ u64 __init kaslr_early_init(u64 dt_phys)
* attempt at mapping the FDT in setup_machine()
*/
early_fixmap_init();
fdt = __fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL);
fdt = fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL);
if (!fdt)
return 0;

View File

@ -170,9 +170,13 @@ static void __init smp_build_mpidr_hash(void)
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)
memblock_reserve(dt_phys, size);
if (!dt_virt || !early_init_dt_scan(dt_virt)) {
pr_crit("\n"
"Error: invalid device tree blob at physical address %pa (virtual address 0x%p)\n"
@ -184,6 +188,9 @@ 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;

View File

@ -876,7 +876,7 @@ void __set_fixmap(enum fixed_addresses idx,
}
}
void *__init __fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
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;
@ -929,19 +929,6 @@ void *__init __fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
return dt_virt;
}
void *__init fixmap_remap_fdt(phys_addr_t dt_phys)
{
void *dt_virt;
int size;
dt_virt = __fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL_RO);
if (!dt_virt)
return NULL;
memblock_reserve(dt_phys, size);
return dt_virt;
}
int __init arch_ioremap_p4d_supported(void)
{
return 0;