Include as much of the read-only data in the replication as we can
without needing to move away from the generic RO_DATA() macro in
the linker script.
Unfortunately, the read-only data section is immedaitely followed
by the read-only after init data with no page alignment, which
means we can't have separate mappings for the read-only data
section and everything else. Changing that would mean replacing
the generic RO_DATA() macro which increases the maintenance burden.
however, this is likely not worth the effort as the majority of
read-only data will be covered.
Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
---
arch/arm64/mm/ktext.c | 2 +-
arch/arm64/mm/mmu.c | 21 ++++++++++++++++++---
2 files changed, 19 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/mm/ktext.c b/arch/arm64/mm/ktext.c
index 6692759e78a8..6265a2db449b 100644
--- a/arch/arm64/mm/ktext.c
+++ b/arch/arm64/mm/ktext.c
@@ -101,7 +101,7 @@ void ktext_replication_patch_alternative(__le32 *src, int nr_inst)
/* Allocate page tables and memory for the replicated kernel texts. */
void __init ktext_replication_init(void)
{
- size_t size = _etext - _stext;
+ size_t size = __end_rodata - _stext;
int kidx = pgd_index((phys_addr_t)KERNEL_START);
int nid;
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index fb9c476605d1..bf674bdaf336 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -752,11 +752,26 @@ static pgprot_t __init kernel_text_pgprot(void)
#ifdef CONFIG_REPLICATE_KTEXT
void __init create_kernel_nid_map(pgd_t *pgdp, void *ktext)
{
+ phys_addr_t pa_ktext;
+ size_t ro_offset;
+ void *ro_end;
pgprot_t text_prot = kernel_text_pgprot();
- create_kernel_mapping(pgdp, __pa(ktext), _stext, _etext, text_prot, 0);
- create_kernel_mapping(pgdp, __pa_symbol(__start_rodata),
- __start_rodata, __inittext_begin,
+ pa_ktext = __pa(ktext);
+ ro_offset = __pa_symbol(__start_rodata) - __pa_symbol(_stext);
+ /*
+ * We must not cover the read-only data after init, since this
+ * is written to during boot, and thus must be shared between
+ * the NUMA nodes.
+ */
+ ro_end = PTR_ALIGN_DOWN((void *)__start_ro_after_init, PAGE_SIZE);
+
+ create_kernel_mapping(pgdp, pa_ktext, _stext, _etext, text_prot, 0);
+ create_kernel_mapping(pgdp, pa_ktext + ro_offset,
+ __start_rodata, ro_end,
+ PAGE_KERNEL, NO_CONT_MAPPINGS);
+ create_kernel_mapping(pgdp, __pa_symbol(ro_end),
+ ro_end, __inittext_begin,
PAGE_KERNEL, NO_CONT_MAPPINGS);
create_kernel_mapping(pgdp, __pa_symbol(__inittext_begin),
__inittext_begin, __inittext_end,
--
2.30.2
