From a2feeb2c2ecbd9c9206d66f238ca710b760c9ef5 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 19 May 2020 05:49:27 +0000 Subject: [PATCH] powerpc/8xx: Implement dedicated kasan_init_region() Implement a kasan_init_region() dedicated to 8xx that allocates KASAN regions using huge pages. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/d2d60202a8821dc81cffe6ff59cc13c15b7e4bb6.1589866984.git.christophe.leroy@csgroup.eu --- arch/powerpc/mm/kasan/8xx.c | 74 ++++++++++++++++++++++++++++++++++++++++++ arch/powerpc/mm/kasan/Makefile | 1 + 2 files changed, 75 insertions(+) create mode 100644 arch/powerpc/mm/kasan/8xx.c diff --git a/arch/powerpc/mm/kasan/8xx.c b/arch/powerpc/mm/kasan/8xx.c new file mode 100644 index 000000000000..db4ef44af22f --- /dev/null +++ b/arch/powerpc/mm/kasan/8xx.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define DISABLE_BRANCH_PROFILING + +#include +#include +#include +#include + +static int __init +kasan_init_shadow_8M(unsigned long k_start, unsigned long k_end, void *block) +{ + pmd_t *pmd = pmd_ptr_k(k_start); + unsigned long k_cur, k_next; + + for (k_cur = k_start; k_cur != k_end; k_cur = k_next, pmd += 2, block += SZ_8M) { + pte_basic_t *new; + + k_next = pgd_addr_end(k_cur, k_end); + k_next = pgd_addr_end(k_next, k_end); + if ((void *)pmd_page_vaddr(*pmd) != kasan_early_shadow_pte) + continue; + + new = memblock_alloc(sizeof(pte_basic_t), SZ_4K); + if (!new) + return -ENOMEM; + + *new = pte_val(pte_mkhuge(pfn_pte(PHYS_PFN(__pa(block)), PAGE_KERNEL))); + + hugepd_populate_kernel((hugepd_t *)pmd, (pte_t *)new, PAGE_SHIFT_8M); + hugepd_populate_kernel((hugepd_t *)pmd + 1, (pte_t *)new, PAGE_SHIFT_8M); + } + return 0; +} + +int __init kasan_init_region(void *start, size_t size) +{ + unsigned long k_start = (unsigned long)kasan_mem_to_shadow(start); + unsigned long k_end = (unsigned long)kasan_mem_to_shadow(start + size); + unsigned long k_cur; + int ret; + void *block; + + block = memblock_alloc(k_end - k_start, SZ_8M); + if (!block) + return -ENOMEM; + + if (IS_ALIGNED(k_start, SZ_8M)) { + kasan_init_shadow_8M(k_start, ALIGN_DOWN(k_end, SZ_8M), block); + k_cur = ALIGN_DOWN(k_end, SZ_8M); + if (k_cur == k_end) + goto finish; + } else { + k_cur = k_start; + } + + ret = kasan_init_shadow_page_tables(k_start, k_end); + if (ret) + return ret; + + for (; k_cur < k_end; k_cur += PAGE_SIZE) { + pmd_t *pmd = pmd_ptr_k(k_cur); + void *va = block + k_cur - k_start; + pte_t pte = pfn_pte(PHYS_PFN(__pa(va)), PAGE_KERNEL); + + if (k_cur < ALIGN_DOWN(k_end, SZ_512K)) + pte = pte_mkhuge(pte); + + __set_pte_at(&init_mm, k_cur, pte_offset_kernel(pmd, k_cur), pte, 0); + } +finish: + flush_tlb_kernel_range(k_start, k_end); + return 0; +} diff --git a/arch/powerpc/mm/kasan/Makefile b/arch/powerpc/mm/kasan/Makefile index 6577897673dd..440038ea79f1 100644 --- a/arch/powerpc/mm/kasan/Makefile +++ b/arch/powerpc/mm/kasan/Makefile @@ -3,3 +3,4 @@ KASAN_SANITIZE := n obj-$(CONFIG_PPC32) += kasan_init_32.o +obj-$(CONFIG_PPC_8xx) += 8xx.o -- 2.11.0