diff options
| author | Nicholas Miehlbradt <nicholas@linux.ibm.com> | 2022-09-26 07:57:26 +0000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2022-09-28 19:22:10 +1000 |
| commit | a5edf9815dd739fce660b4c8658f61b7d2517042 (patch) | |
| tree | ee622d9e25b2b4a10d9447c726e7c678ba7871bc /arch/powerpc/include/asm | |
| parent | d7902d31cbc3bf72722768831a684b0286ccd523 (diff) | |
powerpc/64s: Enable KFENCE on book3s64
KFENCE support was added for ppc32 in commit 90cbac0e995d
("powerpc: Enable KFENCE for PPC32").
Enable KFENCE on ppc64 architecture with hash and radix MMUs.
It uses the same mechanism as debug pagealloc to
protect/unprotect pages. All KFENCE kunit tests pass on both
MMUs.
KFENCE memory is initially allocated using memblock but is
later marked as SLAB allocated. This necessitates the change
to __pud_free to ensure that the KFENCE pages are freed
appropriately.
Based on previous work by Christophe Leroy and Jordan Niethe.
Signed-off-by: Nicholas Miehlbradt <nicholas@linux.ibm.com>
Reviewed-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220926075726.2846-4-nicholas@linux.ibm.com
Diffstat (limited to 'arch/powerpc/include/asm')
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/pgalloc.h | 6 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/pgtable.h | 2 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/kfence.h | 15 |
3 files changed, 20 insertions, 3 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/pgalloc.h b/arch/powerpc/include/asm/book3s/64/pgalloc.h index e1af0b394ceb..dd2cff53a111 100644 --- a/arch/powerpc/include/asm/book3s/64/pgalloc.h +++ b/arch/powerpc/include/asm/book3s/64/pgalloc.h @@ -113,9 +113,11 @@ static inline void __pud_free(pud_t *pud) /* * Early pud pages allocated via memblock allocator - * can't be directly freed to slab + * can't be directly freed to slab. KFENCE pages have + * both reserved and slab flags set so need to be freed + * kmem_cache_free. */ - if (PageReserved(page)) + if (PageReserved(page) && !PageSlab(page)) free_reserved_page(page); else kmem_cache_free(PGT_CACHE(PUD_CACHE_INDEX), pud); diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index b5f8264cc980..c436d8422654 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -1106,7 +1106,7 @@ static inline void vmemmap_remove_mapping(unsigned long start, } #endif -#ifdef CONFIG_DEBUG_PAGEALLOC +#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KFENCE) static inline void __kernel_map_pages(struct page *page, int numpages, int enable) { if (radix_enabled()) diff --git a/arch/powerpc/include/asm/kfence.h b/arch/powerpc/include/asm/kfence.h index a9846b68c6b9..6fd2b4d486c5 100644 --- a/arch/powerpc/include/asm/kfence.h +++ b/arch/powerpc/include/asm/kfence.h @@ -11,11 +11,25 @@ #include <linux/mm.h> #include <asm/pgtable.h> +#ifdef CONFIG_PPC64_ELF_ABI_V1 +#define ARCH_FUNC_PREFIX "." +#endif + static inline bool arch_kfence_init_pool(void) { return true; } +#ifdef CONFIG_PPC64 +static inline bool kfence_protect_page(unsigned long addr, bool protect) +{ + struct page *page = virt_to_page(addr); + + __kernel_map_pages(page, 1, !protect); + + return true; +} +#else static inline bool kfence_protect_page(unsigned long addr, bool protect) { pte_t *kpte = virt_to_kpte(addr); @@ -29,5 +43,6 @@ static inline bool kfence_protect_page(unsigned long addr, bool protect) return true; } +#endif #endif /* __ASM_POWERPC_KFENCE_H */ |