[PATCH v3 6/7] arm64: map linear region as non-executable
Ard Biesheuvel
ard.biesheuvel at linaro.org
Mon Nov 16 03:23:17 PST 2015
Now that we moved the kernel text out of the linear region, there
is no longer a reason to map the linear region as executable. This
also allows us to completely get rid of the __map_mem() variant that
only maps some of it executable if CONFIG_DEBUG_RODATA is selected.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
---
arch/arm64/mm/mmu.c | 41 +-------------------
1 file changed, 2 insertions(+), 39 deletions(-)
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index c7ba171951c8..526eeb7e1e97 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -357,47 +357,10 @@ static void create_mapping_late(phys_addr_t phys, unsigned long virt,
phys, virt, size, prot, late_alloc);
}
-#ifdef CONFIG_DEBUG_RODATA
static void __init __map_memblock(phys_addr_t start, phys_addr_t end)
{
- /*
- * Set up the executable regions using the existing section mappings
- * for now. This will get more fine grained later once all memory
- * is mapped
- */
- unsigned long kernel_x_start = round_down(__pa(_stext), SWAPPER_BLOCK_SIZE);
- unsigned long kernel_x_end = round_up(__pa(__init_end), SWAPPER_BLOCK_SIZE);
-
- if (end < kernel_x_start) {
- create_mapping(start, __phys_to_virt(start),
- end - start, PAGE_KERNEL);
- } else if (start >= kernel_x_end) {
- create_mapping(start, __phys_to_virt(start),
- end - start, PAGE_KERNEL);
- } else {
- if (start < kernel_x_start)
- create_mapping(start, __phys_to_virt(start),
- kernel_x_start - start,
- PAGE_KERNEL);
- create_mapping(kernel_x_start,
- __phys_to_virt(kernel_x_start),
- kernel_x_end - kernel_x_start,
- PAGE_KERNEL_EXEC);
- if (kernel_x_end < end)
- create_mapping(kernel_x_end,
- __phys_to_virt(kernel_x_end),
- end - kernel_x_end,
- PAGE_KERNEL);
- }
-
-}
-#else
-static void __init __map_memblock(phys_addr_t start, phys_addr_t end)
-{
- create_mapping(start, __phys_to_virt(start), end - start,
- PAGE_KERNEL_EXEC);
+ create_mapping(start, __phys_to_virt(start), end - start, PAGE_KERNEL);
}
-#endif
struct bootstrap_pgtables {
pte_t pte[PTRS_PER_PTE];
@@ -471,7 +434,7 @@ static unsigned long __init bootstrap_region(struct bootstrap_pgtables *reg,
SWAPPER_BLOCK_SIZE));
create_mapping(__pa(vstart - va_offset), vstart, vend - vstart,
- PAGE_KERNEL_EXEC);
+ PAGE_KERNEL);
return vend;
}
--
1.9.1
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