diff options
| author | Will Deacon <will@kernel.org> | 2021-06-24 14:05:25 +0100 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2021-06-24 14:05:25 +0100 |
| commit | fdceddb06a5ff5ad3894cf9e8124d5af38ac5793 (patch) | |
| tree | 1c0e225ad623ec5d6d02c42f400b2202f4567dc0 /arch/arm64/mm | |
| parent | 81ad4bb1fe91d28d793d801e462a284c7f82cc40 (diff) | |
| parent | c275c5c6d50a0518cdb0584e85905d10e7cefc6e (diff) | |
Merge branch 'for-next/mte' into for-next/core
KASAN optimisations for the hardware tagging (MTE) implementation.
* for-next/mte:
kasan: disable freed user page poisoning with HW tags
arm64: mte: handle tags zeroing at page allocation time
kasan: use separate (un)poison implementation for integrated init
mm: arch: remove indirection level in alloc_zeroed_user_highpage_movable()
kasan: speed up mte_set_mem_tag_range
Diffstat (limited to 'arch/arm64/mm')
| -rw-r--r-- | arch/arm64/mm/fault.c | 26 | ||||
| -rw-r--r-- | arch/arm64/mm/proc.S | 10 |
2 files changed, 33 insertions, 3 deletions
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index d0f972a45099..349c488765ca 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -919,3 +919,29 @@ void do_debug_exception(unsigned long addr_if_watchpoint, unsigned int esr, debug_exception_exit(regs); } NOKPROBE_SYMBOL(do_debug_exception); + +/* + * Used during anonymous page fault handling. + */ +struct page *alloc_zeroed_user_highpage_movable(struct vm_area_struct *vma, + unsigned long vaddr) +{ + gfp_t flags = GFP_HIGHUSER_MOVABLE | __GFP_ZERO; + + /* + * If the page is mapped with PROT_MTE, initialise the tags at the + * point of allocation and page zeroing as this is usually faster than + * separate DC ZVA and STGM. + */ + if (vma->vm_flags & VM_MTE) + flags |= __GFP_ZEROTAGS; + + return alloc_page_vma(flags, vma, vaddr); +} + +void tag_clear_highpage(struct page *page) +{ + mte_zero_clear_page_tags(page_address(page)); + page_kasan_tag_reset(page); + set_bit(PG_mte_tagged, &page->flags); +} diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 9b0ad5ba77d2..35936c5ae1ce 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -46,9 +46,13 @@ #endif #ifdef CONFIG_KASAN_HW_TAGS -#define TCR_KASAN_HW_FLAGS SYS_TCR_EL1_TCMA1 | TCR_TBI1 | TCR_TBID1 +#define TCR_MTE_FLAGS SYS_TCR_EL1_TCMA1 | TCR_TBI1 | TCR_TBID1 #else -#define TCR_KASAN_HW_FLAGS 0 +/* + * The mte_zero_clear_page_tags() implementation uses DC GZVA, which relies on + * TBI being enabled at EL1. + */ +#define TCR_MTE_FLAGS TCR_TBI1 | TCR_TBID1 #endif /* @@ -454,7 +458,7 @@ SYM_FUNC_START(__cpu_setup) msr_s SYS_TFSRE0_EL1, xzr /* set the TCR_EL1 bits */ - mov_q x10, TCR_KASAN_HW_FLAGS + mov_q x10, TCR_MTE_FLAGS orr tcr, tcr, x10 1: #endif |