--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KASAN for 64-bit Book3e powerpc
+ *
+ * Copyright 2022, Christophe Leroy, CS GROUP France
+ */
+
+#define DISABLE_BRANCH_PROFILING
+
+#include <linux/kasan.h>
+#include <linux/printk.h>
+#include <linux/memblock.h>
+#include <linux/set_memory.h>
+
+#include <asm/pgalloc.h>
+
+static inline bool kasan_pud_table(p4d_t p4d)
+{
+ return p4d_page(p4d) == virt_to_page(lm_alias(kasan_early_shadow_pud));
+}
+
+static inline bool kasan_pmd_table(pud_t pud)
+{
+ return pud_page(pud) == virt_to_page(lm_alias(kasan_early_shadow_pmd));
+}
+
+static inline bool kasan_pte_table(pmd_t pmd)
+{
+ return pmd_page(pmd) == virt_to_page(lm_alias(kasan_early_shadow_pte));
+}
+
+static int __init kasan_map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot)
+{
+ pgd_t *pgdp;
+ p4d_t *p4dp;
+ pud_t *pudp;
+ pmd_t *pmdp;
+ pte_t *ptep;
+
+ pgdp = pgd_offset_k(ea);
+ p4dp = p4d_offset(pgdp, ea);
+ if (kasan_pud_table(*p4dp)) {
+ pudp = memblock_alloc(PUD_TABLE_SIZE, PUD_TABLE_SIZE);
+ memcpy(pudp, kasan_early_shadow_pud, PUD_TABLE_SIZE);
+ p4d_populate(&init_mm, p4dp, pudp);
+ }
+ pudp = pud_offset(p4dp, ea);
+ if (kasan_pmd_table(*pudp)) {
+ pmdp = memblock_alloc(PMD_TABLE_SIZE, PMD_TABLE_SIZE);
+ memcpy(pmdp, kasan_early_shadow_pmd, PMD_TABLE_SIZE);
+ pud_populate(&init_mm, pudp, pmdp);
+ }
+ pmdp = pmd_offset(pudp, ea);
+ if (kasan_pte_table(*pmdp)) {
+ ptep = memblock_alloc(PTE_TABLE_SIZE, PTE_TABLE_SIZE);
+ memcpy(ptep, kasan_early_shadow_pte, PTE_TABLE_SIZE);
+ pmd_populate_kernel(&init_mm, pmdp, ptep);
+ }
+ ptep = pte_offset_kernel(pmdp, ea);
+
+ __set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, prot), 0);
+
+ return 0;
+}
+
+static void __init kasan_init_phys_region(void *start, void *end)
+{
+ unsigned long k_start, k_end, k_cur;
+ void *va;
+
+ if (start >= end)
+ return;
+
+ k_start = ALIGN_DOWN((unsigned long)kasan_mem_to_shadow(start), PAGE_SIZE);
+ k_end = ALIGN((unsigned long)kasan_mem_to_shadow(end), PAGE_SIZE);
+
+ va = memblock_alloc(k_end - k_start, PAGE_SIZE);
+ for (k_cur = k_start; k_cur < k_end; k_cur += PAGE_SIZE, va += PAGE_SIZE)
+ kasan_map_kernel_page(k_cur, __pa(va), PAGE_KERNEL);
+}
+
+void __init kasan_early_init(void)
+{
+ int i;
+ unsigned long addr;
+ pgd_t *pgd = pgd_offset_k(KASAN_SHADOW_START);
+ pte_t zero_pte = pfn_pte(virt_to_pfn(kasan_early_shadow_page), PAGE_KERNEL);
+
+ BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, PGDIR_SIZE));
+ BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PGDIR_SIZE));
+
+ for (i = 0; i < PTRS_PER_PTE; i++)
+ __set_pte_at(&init_mm, (unsigned long)kasan_early_shadow_page,
+ &kasan_early_shadow_pte[i], zero_pte, 0);
+
+ for (i = 0; i < PTRS_PER_PMD; i++)
+ pmd_populate_kernel(&init_mm, &kasan_early_shadow_pmd[i],
+ kasan_early_shadow_pte);
+
+ for (i = 0; i < PTRS_PER_PUD; i++)
+ pud_populate(&init_mm, &kasan_early_shadow_pud[i],
+ kasan_early_shadow_pmd);
+
+ for (addr = KASAN_SHADOW_START; addr != KASAN_SHADOW_END; addr += PGDIR_SIZE)
+ p4d_populate(&init_mm, p4d_offset(pgd++, addr), kasan_early_shadow_pud);
+}
+
+void __init kasan_init(void)
+{
+ phys_addr_t start, end;
+ u64 i;
+ pte_t zero_pte = pfn_pte(virt_to_pfn(kasan_early_shadow_page), PAGE_KERNEL_RO);
+
+ for_each_mem_range(i, &start, &end)
+ kasan_init_phys_region((void *)start, (void *)end);
+
+ if (IS_ENABLED(CONFIG_KASAN_VMALLOC))
+ kasan_remove_zero_shadow((void *)VMALLOC_START, VMALLOC_SIZE);
+
+ for (i = 0; i < PTRS_PER_PTE; i++)
+ __set_pte_at(&init_mm, (unsigned long)kasan_early_shadow_page,
+ &kasan_early_shadow_pte[i], zero_pte, 0);
+
+ flush_tlb_kernel_range(KASAN_SHADOW_START, KASAN_SHADOW_END);
+
+ memset(kasan_early_shadow_page, 0, PAGE_SIZE);
+
+ /* Enable error messages */
+ init_task.kasan_depth = 0;
+ pr_info("KASAN init done\n");
+}
+
+void __init kasan_late_init(void) { }
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