redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

powerpc/mm: Add a helper to select PAGE_KERNEL_RO or PAGE_READONLY 

In a couple of places there is a need to select whether read-only
protection of shadow pages is performed with PAGE_KERNEL_RO or with
PAGE_READONLY.

Add a helper to avoid duplicating the choice.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/9f33f44b9cd741c4a02b3dce7b8ef9438fe2cd2a.1566382750.git.christophe.leroy@c-s.fr
alistair/sunxi64-5.4-dsi
Christophe Leroy 2019-08-21 10:20:00 +00:00 committed by Michael Ellerman
parent 13c7bb3c57
commit 4c0f5d1eb4
1 changed files with 13 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
arch/powerpc/mm/kasan/kasan_init_32.c
View File

@ -12,6 +12,14 @@
#include <asm/code-patching.h>
#include <mm/mmu_decl.h>
static pgprot_t kasan_prot_ro(void)
{
if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE))
return PAGE_READONLY;
return PAGE_KERNEL_RO;
}
static void kasan_populate_pte(pte_t *ptep, pgprot_t prot)
{
unsigned long va = (unsigned long)kasan_early_shadow_page;
@ -26,6 +34,7 @@ static int __ref kasan_init_shadow_page_tables(unsigned long k_start, unsigned l
{
pmd_t *pmd;
unsigned long k_cur, k_next;
pgprot_t prot = kasan_prot_ro();
pmd = pmd_offset(pud_offset(pgd_offset_k(k_start), k_start), k_start);
@ -43,10 +52,7 @@ static int __ref kasan_init_shadow_page_tables(unsigned long k_start, unsigned l
if (!new)
return -ENOMEM;
if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE))
kasan_populate_pte(new, PAGE_READONLY);
else
kasan_populate_pte(new, PAGE_KERNEL_RO);
kasan_populate_pte(new, prot);
smp_wmb(); /* See comment in __pte_alloc */
@ -103,10 +109,9 @@ static int __ref kasan_init_region(void *start, size_t size)
static void __init kasan_remap_early_shadow_ro(void)
{
if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE))
kasan_populate_pte(kasan_early_shadow_pte, PAGE_READONLY);
else
kasan_populate_pte(kasan_early_shadow_pte, PAGE_KERNEL_RO);
pgprot_t prot = kasan_prot_ro();
kasan_populate_pte(kasan_early_shadow_pte, prot);
flush_tlb_kernel_range(KASAN_SHADOW_START, KASAN_SHADOW_END);
}