diff options
Diffstat (limited to 'arch/powerpc/mm')
| -rw-r--r-- | arch/powerpc/mm/book3s64/radix_pgtable.c | 84 | ||||
| -rw-r--r-- | arch/powerpc/mm/init-common.c | 3 |
2 files changed, 83 insertions, 4 deletions
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c index 15e88f1439ec..b0d927009af8 100644 --- a/arch/powerpc/mm/book3s64/radix_pgtable.c +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c @@ -17,6 +17,7 @@ #include <linux/hugetlb.h> #include <linux/string_helpers.h> #include <linux/memory.h> +#include <linux/kfence.h> #include <asm/pgalloc.h> #include <asm/mmu_context.h> @@ -31,6 +32,7 @@ #include <asm/uaccess.h> #include <asm/ultravisor.h> #include <asm/set_memory.h> +#include <asm/kfence.h> #include <trace/events/thp.h> @@ -293,7 +295,8 @@ static unsigned long next_boundary(unsigned long addr, unsigned long end) static int __meminit create_physical_mapping(unsigned long start, unsigned long end, - int nid, pgprot_t _prot) + int nid, pgprot_t _prot, + unsigned long mapping_sz_limit) { unsigned long vaddr, addr, mapping_size = 0; bool prev_exec, exec = false; @@ -301,7 +304,10 @@ static int __meminit create_physical_mapping(unsigned long start, int psize; unsigned long max_mapping_size = memory_block_size; - if (debug_pagealloc_enabled_or_kfence()) + if (mapping_sz_limit < max_mapping_size) + max_mapping_size = mapping_sz_limit; + + if (debug_pagealloc_enabled()) max_mapping_size = PAGE_SIZE; start = ALIGN(start, PAGE_SIZE); @@ -356,8 +362,74 @@ static int __meminit create_physical_mapping(unsigned long start, return 0; } +#ifdef CONFIG_KFENCE +static bool __ro_after_init kfence_early_init = !!CONFIG_KFENCE_SAMPLE_INTERVAL; + +static int __init parse_kfence_early_init(char *arg) +{ + int val; + + if (get_option(&arg, &val)) + kfence_early_init = !!val; + return 0; +} +early_param("kfence.sample_interval", parse_kfence_early_init); + +static inline phys_addr_t alloc_kfence_pool(void) +{ + phys_addr_t kfence_pool; + + /* + * TODO: Support to enable KFENCE after bootup depends on the ability to + * split page table mappings. As such support is not currently + * implemented for radix pagetables, support enabling KFENCE + * only at system startup for now. + * + * After support for splitting mappings is available on radix, + * alloc_kfence_pool() & map_kfence_pool() can be dropped and + * mapping for __kfence_pool memory can be + * split during arch_kfence_init_pool(). + */ + if (!kfence_early_init) + goto no_kfence; + + kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE); + if (!kfence_pool) + goto no_kfence; + + memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE); + return kfence_pool; + +no_kfence: + disable_kfence(); + return 0; +} + +static inline void map_kfence_pool(phys_addr_t kfence_pool) +{ + if (!kfence_pool) + return; + + if (create_physical_mapping(kfence_pool, kfence_pool + KFENCE_POOL_SIZE, + -1, PAGE_KERNEL, PAGE_SIZE)) + goto err; + + memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE); + __kfence_pool = __va(kfence_pool); + return; + +err: + memblock_phys_free(kfence_pool, KFENCE_POOL_SIZE); + disable_kfence(); +} +#else +static inline phys_addr_t alloc_kfence_pool(void) { return 0; } +static inline void map_kfence_pool(phys_addr_t kfence_pool) { } +#endif + static void __init radix_init_pgtable(void) { + phys_addr_t kfence_pool; unsigned long rts_field; phys_addr_t start, end; u64 i; @@ -365,6 +437,8 @@ static void __init radix_init_pgtable(void) /* We don't support slb for radix */ slb_set_size(0); + kfence_pool = alloc_kfence_pool(); + /* * Create the linear mapping */ @@ -381,9 +455,11 @@ static void __init radix_init_pgtable(void) } WARN_ON(create_physical_mapping(start, end, - -1, PAGE_KERNEL)); + -1, PAGE_KERNEL, ~0UL)); } + map_kfence_pool(kfence_pool); + if (!cpu_has_feature(CPU_FTR_HVMODE) && cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG)) { /* @@ -875,7 +951,7 @@ int __meminit radix__create_section_mapping(unsigned long start, } return create_physical_mapping(__pa(start), __pa(end), - nid, prot); + nid, prot, ~0UL); } int __meminit radix__remove_section_mapping(unsigned long start, unsigned long end) diff --git a/arch/powerpc/mm/init-common.c b/arch/powerpc/mm/init-common.c index d3a7726ecf51..21131b96d209 100644 --- a/arch/powerpc/mm/init-common.c +++ b/arch/powerpc/mm/init-common.c @@ -31,6 +31,9 @@ EXPORT_SYMBOL_GPL(kernstart_virt_addr); bool disable_kuep = !IS_ENABLED(CONFIG_PPC_KUEP); bool disable_kuap = !IS_ENABLED(CONFIG_PPC_KUAP); +#ifdef CONFIG_KFENCE +bool __ro_after_init kfence_disabled; +#endif static int __init parse_nosmep(char *p) { |