diff options
Diffstat (limited to 'arch/s390/mm/kasan_init.c')
| -rw-r--r-- | arch/s390/mm/kasan_init.c | 157 |
1 files changed, 67 insertions, 90 deletions
diff --git a/arch/s390/mm/kasan_init.c b/arch/s390/mm/kasan_init.c index 06345616a646..9f988d4582ed 100644 --- a/arch/s390/mm/kasan_init.c +++ b/arch/s390/mm/kasan_init.c @@ -2,8 +2,8 @@ #include <linux/kasan.h> #include <linux/sched/task.h> #include <linux/memblock.h> +#include <linux/pgtable.h> #include <asm/pgalloc.h> -#include <asm/pgtable.h> #include <asm/kasan.h> #include <asm/mem_detect.h> #include <asm/processor.h> @@ -11,6 +11,7 @@ #include <asm/facility.h> #include <asm/sections.h> #include <asm/setup.h> +#include <asm/uv.h> static unsigned long segment_pos __initdata; static unsigned long segment_low __initdata; @@ -85,7 +86,7 @@ enum populate_mode { POPULATE_ZERO_SHADOW, POPULATE_SHALLOW }; -static void __init kasan_early_vmemmap_populate(unsigned long address, +static void __init kasan_early_pgtable_populate(unsigned long address, unsigned long end, enum populate_mode mode) { @@ -99,9 +100,16 @@ static void __init kasan_early_vmemmap_populate(unsigned long address, pgt_prot_zero = pgprot_val(PAGE_KERNEL_RO); if (!has_nx) pgt_prot_zero &= ~_PAGE_NOEXEC; - pgt_prot = pgprot_val(PAGE_KERNEL_EXEC); - sgt_prot = pgprot_val(SEGMENT_KERNEL_EXEC); + pgt_prot = pgprot_val(PAGE_KERNEL); + sgt_prot = pgprot_val(SEGMENT_KERNEL); + if (!has_nx || mode == POPULATE_ONE2ONE) { + pgt_prot &= ~_PAGE_NOEXEC; + sgt_prot &= ~_SEGMENT_ENTRY_NOEXEC; + } + /* + * The first 1MB of 1:1 mapping is mapped with 4KB pages + */ while (address < end) { pg_dir = pgd_offset_k(address); if (pgd_none(*pg_dir)) { @@ -117,8 +125,7 @@ static void __init kasan_early_vmemmap_populate(unsigned long address, pgd_populate(&init_mm, pg_dir, p4_dir); } - if (IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING) && - mode == POPULATE_SHALLOW) { + if (mode == POPULATE_SHALLOW) { address = (address + P4D_SIZE) & P4D_MASK; continue; } @@ -137,12 +144,6 @@ static void __init kasan_early_vmemmap_populate(unsigned long address, p4d_populate(&init_mm, p4_dir, pu_dir); } - if (!IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING) && - mode == POPULATE_SHALLOW) { - address = (address + PUD_SIZE) & PUD_MASK; - continue; - } - pu_dir = pud_offset(p4_dir, address); if (pud_none(*pu_dir)) { if (mode == POPULATE_ZERO_SHADOW && @@ -159,30 +160,26 @@ static void __init kasan_early_vmemmap_populate(unsigned long address, pm_dir = pmd_offset(pu_dir, address); if (pmd_none(*pm_dir)) { - if (mode == POPULATE_ZERO_SHADOW && - IS_ALIGNED(address, PMD_SIZE) && + if (IS_ALIGNED(address, PMD_SIZE) && end - address >= PMD_SIZE) { - pmd_populate(&init_mm, pm_dir, - kasan_early_shadow_pte); - address = (address + PMD_SIZE) & PMD_MASK; - continue; - } - /* the first megabyte of 1:1 is mapped with 4k pages */ - if (has_edat && address && end - address >= PMD_SIZE && - mode != POPULATE_ZERO_SHADOW) { - void *page; - - if (mode == POPULATE_ONE2ONE) { - page = (void *)address; - } else { - page = kasan_early_alloc_segment(); - memset(page, 0, _SEGMENT_SIZE); + if (mode == POPULATE_ZERO_SHADOW) { + pmd_populate(&init_mm, pm_dir, kasan_early_shadow_pte); + address = (address + PMD_SIZE) & PMD_MASK; + continue; + } else if (has_edat && address) { + void *page; + + if (mode == POPULATE_ONE2ONE) { + page = (void *)address; + } else { + page = kasan_early_alloc_segment(); + memset(page, 0, _SEGMENT_SIZE); + } + set_pmd(pm_dir, __pmd(__pa(page) | sgt_prot)); + address = (address + PMD_SIZE) & PMD_MASK; + continue; } - pmd_val(*pm_dir) = __pa(page) | sgt_prot; - address = (address + PMD_SIZE) & PMD_MASK; - continue; } - pt_dir = kasan_early_pte_alloc(); pmd_populate(&init_mm, pm_dir, pt_dir); } else if (pmd_large(*pm_dir)) { @@ -197,16 +194,16 @@ static void __init kasan_early_vmemmap_populate(unsigned long address, switch (mode) { case POPULATE_ONE2ONE: page = (void *)address; - pte_val(*pt_dir) = __pa(page) | pgt_prot; + set_pte(pt_dir, __pte(__pa(page) | pgt_prot)); break; case POPULATE_MAP: page = kasan_early_alloc_pages(0); memset(page, 0, PAGE_SIZE); - pte_val(*pt_dir) = __pa(page) | pgt_prot; + set_pte(pt_dir, __pte(__pa(page) | pgt_prot)); break; case POPULATE_ZERO_SHADOW: page = kasan_early_shadow_page; - pte_val(*pt_dir) = __pa(page) | pgt_prot_zero; + set_pte(pt_dir, __pte(__pa(page) | pgt_prot_zero)); break; case POPULATE_SHALLOW: /* should never happen */ @@ -254,12 +251,9 @@ static void __init kasan_early_detect_facilities(void) void __init kasan_early_init(void) { - unsigned long untracked_mem_end; unsigned long shadow_alloc_size; unsigned long initrd_end; - unsigned long asce_type; unsigned long memsize; - unsigned long vmax; unsigned long pgt_prot = pgprot_val(PAGE_KERNEL_RO); pte_t pte_z; pmd_t pmd_z = __pmd(__pa(kasan_early_shadow_pte) | _SEGMENT_ENTRY); @@ -274,30 +268,23 @@ void __init kasan_early_init(void) memsize = get_mem_detect_end(); if (!memsize) kasan_early_panic("cannot detect physical memory size\n"); - /* respect mem= cmdline parameter */ - if (memory_end_set && memsize > memory_end) - memsize = memory_end; - if (IS_ENABLED(CONFIG_CRASH_DUMP) && OLDMEM_BASE) - memsize = min(memsize, OLDMEM_SIZE); - memsize = min(memsize, KASAN_SHADOW_START); - - if (IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING)) { - /* 4 level paging */ - BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, P4D_SIZE)); - BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, P4D_SIZE)); - crst_table_init((unsigned long *)early_pg_dir, - _REGION2_ENTRY_EMPTY); - untracked_mem_end = vmax = _REGION1_SIZE; - asce_type = _ASCE_TYPE_REGION2; - } else { - /* 3 level paging */ - BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, PUD_SIZE)); - BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PUD_SIZE)); - crst_table_init((unsigned long *)early_pg_dir, - _REGION3_ENTRY_EMPTY); - untracked_mem_end = vmax = _REGION2_SIZE; - asce_type = _ASCE_TYPE_REGION3; - } + /* + * Kasan currently supports standby memory but only if it follows + * online memory (default allocation), i.e. no memory holes. + * - memsize represents end of online memory + * - ident_map_size represents online + standby and memory limits + * accounted. + * Kasan maps "memsize" right away. + * [0, memsize] - as identity mapping + * [__sha(0), __sha(memsize)] - shadow memory for identity mapping + * The rest [memsize, ident_map_size] if memsize < ident_map_size + * could be mapped/unmapped dynamically later during memory hotplug. + */ + memsize = min(memsize, ident_map_size); + + BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, P4D_SIZE)); + BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, P4D_SIZE)); + crst_table_init((unsigned long *)early_pg_dir, _REGION2_ENTRY_EMPTY); /* init kasan zero shadow */ crst_table_init((unsigned long *)kasan_early_shadow_p4d, @@ -312,7 +299,7 @@ void __init kasan_early_init(void) pgalloc_low = round_up((unsigned long)_end, _SEGMENT_SIZE); if (IS_ENABLED(CONFIG_BLK_DEV_INITRD)) { initrd_end = - round_up(INITRD_START + INITRD_SIZE, _SEGMENT_SIZE); + round_up(initrd_data.start + initrd_data.size, _SEGMENT_SIZE); pgalloc_low = max(pgalloc_low, initrd_end); } @@ -363,24 +350,25 @@ void __init kasan_early_init(void) * +-----------------+ +- shadow end ---+ */ /* populate kasan shadow (for identity mapping and zero page mapping) */ - kasan_early_vmemmap_populate(__sha(0), __sha(memsize), POPULATE_MAP); - if (IS_ENABLED(CONFIG_MODULES)) - untracked_mem_end = vmax - MODULES_LEN; + kasan_early_pgtable_populate(__sha(0), __sha(memsize), POPULATE_MAP); if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) { - untracked_mem_end = vmax - vmalloc_size - MODULES_LEN; /* shallowly populate kasan shadow for vmalloc and modules */ - kasan_early_vmemmap_populate(__sha(untracked_mem_end), - __sha(vmax), POPULATE_SHALLOW); + kasan_early_pgtable_populate(__sha(VMALLOC_START), __sha(MODULES_END), + POPULATE_SHALLOW); } /* populate kasan shadow for untracked memory */ - kasan_early_vmemmap_populate(__sha(max_physmem_end), - __sha(untracked_mem_end), + kasan_early_pgtable_populate(__sha(ident_map_size), + IS_ENABLED(CONFIG_KASAN_VMALLOC) ? + __sha(VMALLOC_START) : + __sha(MODULES_VADDR), + POPULATE_ZERO_SHADOW); + kasan_early_pgtable_populate(__sha(MODULES_END), __sha(_REGION1_SIZE), POPULATE_ZERO_SHADOW); /* memory allocated for identity mapping structs will be freed later */ pgalloc_freeable = pgalloc_pos; /* populate identity mapping */ - kasan_early_vmemmap_populate(0, memsize, POPULATE_ONE2ONE); - kasan_set_pgd(early_pg_dir, asce_type); + kasan_early_pgtable_populate(0, memsize, POPULATE_ONE2ONE); + kasan_set_pgd(early_pg_dir, _ASCE_TYPE_REGION2); kasan_enable_dat(); /* enable kasan */ init_task.kasan_depth = 0; @@ -388,7 +376,7 @@ void __init kasan_early_init(void) sclp_early_printk("KernelAddressSanitizer initialized\n"); } -void __init kasan_copy_shadow(pgd_t *pg_dir) +void __init kasan_copy_shadow_mapping(void) { /* * At this point we are still running on early pages setup early_pg_dir, @@ -400,27 +388,16 @@ void __init kasan_copy_shadow(pgd_t *pg_dir) pgd_t *pg_dir_dst; p4d_t *p4_dir_src; p4d_t *p4_dir_dst; - pud_t *pu_dir_src; - pud_t *pu_dir_dst; pg_dir_src = pgd_offset_raw(early_pg_dir, KASAN_SHADOW_START); - pg_dir_dst = pgd_offset_raw(pg_dir, KASAN_SHADOW_START); + pg_dir_dst = pgd_offset_raw(init_mm.pgd, KASAN_SHADOW_START); p4_dir_src = p4d_offset(pg_dir_src, KASAN_SHADOW_START); p4_dir_dst = p4d_offset(pg_dir_dst, KASAN_SHADOW_START); - if (!p4d_folded(*p4_dir_src)) { - /* 4 level paging */ - memcpy(p4_dir_dst, p4_dir_src, - (KASAN_SHADOW_SIZE >> P4D_SHIFT) * sizeof(p4d_t)); - return; - } - /* 3 level paging */ - pu_dir_src = pud_offset(p4_dir_src, KASAN_SHADOW_START); - pu_dir_dst = pud_offset(p4_dir_dst, KASAN_SHADOW_START); - memcpy(pu_dir_dst, pu_dir_src, - (KASAN_SHADOW_SIZE >> PUD_SHIFT) * sizeof(pud_t)); + memcpy(p4_dir_dst, p4_dir_src, + (KASAN_SHADOW_SIZE >> P4D_SHIFT) * sizeof(p4d_t)); } void __init kasan_free_early_identity(void) { - memblock_free(pgalloc_pos, pgalloc_freeable - pgalloc_pos); + memblock_phys_free(pgalloc_pos, pgalloc_freeable - pgalloc_pos); } |