diff options
Diffstat (limited to 'arch/arm64/mm')
-rw-r--r-- | arch/arm64/mm/Makefile | 3 | ||||
-rw-r--r-- | arch/arm64/mm/context.c | 105 | ||||
-rw-r--r-- | arch/arm64/mm/copypage.c | 25 | ||||
-rw-r--r-- | arch/arm64/mm/extable.c | 4 | ||||
-rw-r--r-- | arch/arm64/mm/fault.c | 13 | ||||
-rw-r--r-- | arch/arm64/mm/mmu.c | 20 | ||||
-rw-r--r-- | arch/arm64/mm/mteswap.c | 83 | ||||
-rw-r--r-- | arch/arm64/mm/numa.c | 8 | ||||
-rw-r--r-- | arch/arm64/mm/pageattr.c | 1 | ||||
-rw-r--r-- | arch/arm64/mm/proc.S | 32 | ||||
-rw-r--r-- | arch/arm64/mm/ptdump.c (renamed from arch/arm64/mm/dump.c) | 6 |
11 files changed, 275 insertions, 25 deletions
diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile index d91030f0ffee..5ead3c3de3b6 100644 --- a/arch/arm64/mm/Makefile +++ b/arch/arm64/mm/Makefile @@ -4,10 +4,11 @@ obj-y := dma-mapping.o extable.o fault.o init.o \ ioremap.o mmap.o pgd.o mmu.o \ context.o proc.o pageattr.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o -obj-$(CONFIG_PTDUMP_CORE) += dump.o +obj-$(CONFIG_PTDUMP_CORE) += ptdump.o obj-$(CONFIG_PTDUMP_DEBUGFS) += ptdump_debugfs.o obj-$(CONFIG_NUMA) += numa.o obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o +obj-$(CONFIG_ARM64_MTE) += mteswap.o KASAN_SANITIZE_physaddr.o += n obj-$(CONFIG_KASAN) += kasan_init.o diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c index 9b11c096a042..001737a8f309 100644 --- a/arch/arm64/mm/context.c +++ b/arch/arm64/mm/context.c @@ -27,6 +27,10 @@ static DEFINE_PER_CPU(atomic64_t, active_asids); static DEFINE_PER_CPU(u64, reserved_asids); static cpumask_t tlb_flush_pending; +static unsigned long max_pinned_asids; +static unsigned long nr_pinned_asids; +static unsigned long *pinned_asid_map; + #define ASID_MASK (~GENMASK(asid_bits - 1, 0)) #define ASID_FIRST_VERSION (1UL << asid_bits) @@ -72,7 +76,7 @@ void verify_cpu_asid_bits(void) } } -static void set_kpti_asid_bits(void) +static void set_kpti_asid_bits(unsigned long *map) { unsigned int len = BITS_TO_LONGS(NUM_USER_ASIDS) * sizeof(unsigned long); /* @@ -81,13 +85,15 @@ static void set_kpti_asid_bits(void) * is set, then the ASID will map only userspace. Thus * mark even as reserved for kernel. */ - memset(asid_map, 0xaa, len); + memset(map, 0xaa, len); } static void set_reserved_asid_bits(void) { - if (arm64_kernel_unmapped_at_el0()) - set_kpti_asid_bits(); + if (pinned_asid_map) + bitmap_copy(asid_map, pinned_asid_map, NUM_USER_ASIDS); + else if (arm64_kernel_unmapped_at_el0()) + set_kpti_asid_bits(asid_map); else bitmap_clear(asid_map, 0, NUM_USER_ASIDS); } @@ -166,6 +172,14 @@ static u64 new_context(struct mm_struct *mm) return newasid; /* + * If it is pinned, we can keep using it. Note that reserved + * takes priority, because even if it is also pinned, we need to + * update the generation into the reserved_asids. + */ + if (refcount_read(&mm->context.pinned)) + return newasid; + + /* * We had a valid ASID in a previous life, so try to re-use * it if possible. */ @@ -256,6 +270,71 @@ switch_mm_fastpath: cpu_switch_mm(mm->pgd, mm); } +unsigned long arm64_mm_context_get(struct mm_struct *mm) +{ + unsigned long flags; + u64 asid; + + if (!pinned_asid_map) + return 0; + + raw_spin_lock_irqsave(&cpu_asid_lock, flags); + + asid = atomic64_read(&mm->context.id); + + if (refcount_inc_not_zero(&mm->context.pinned)) + goto out_unlock; + + if (nr_pinned_asids >= max_pinned_asids) { + asid = 0; + goto out_unlock; + } + + if (!asid_gen_match(asid)) { + /* + * We went through one or more rollover since that ASID was + * used. Ensure that it is still valid, or generate a new one. + */ + asid = new_context(mm); + atomic64_set(&mm->context.id, asid); + } + + nr_pinned_asids++; + __set_bit(asid2idx(asid), pinned_asid_map); + refcount_set(&mm->context.pinned, 1); + +out_unlock: + raw_spin_unlock_irqrestore(&cpu_asid_lock, flags); + + asid &= ~ASID_MASK; + + /* Set the equivalent of USER_ASID_BIT */ + if (asid && arm64_kernel_unmapped_at_el0()) + asid |= 1; + + return asid; +} +EXPORT_SYMBOL_GPL(arm64_mm_context_get); + +void arm64_mm_context_put(struct mm_struct *mm) +{ + unsigned long flags; + u64 asid = atomic64_read(&mm->context.id); + + if (!pinned_asid_map) + return; + + raw_spin_lock_irqsave(&cpu_asid_lock, flags); + + if (refcount_dec_and_test(&mm->context.pinned)) { + __clear_bit(asid2idx(asid), pinned_asid_map); + nr_pinned_asids--; + } + + raw_spin_unlock_irqrestore(&cpu_asid_lock, flags); +} +EXPORT_SYMBOL_GPL(arm64_mm_context_put); + /* Errata workaround post TTBRx_EL1 update. */ asmlinkage void post_ttbr_update_workaround(void) { @@ -296,8 +375,11 @@ static int asids_update_limit(void) { unsigned long num_available_asids = NUM_USER_ASIDS; - if (arm64_kernel_unmapped_at_el0()) + if (arm64_kernel_unmapped_at_el0()) { num_available_asids /= 2; + if (pinned_asid_map) + set_kpti_asid_bits(pinned_asid_map); + } /* * Expect allocation after rollover to fail if we don't have at least * one more ASID than CPUs. ASID #0 is reserved for init_mm. @@ -305,6 +387,13 @@ static int asids_update_limit(void) WARN_ON(num_available_asids - 1 <= num_possible_cpus()); pr_info("ASID allocator initialised with %lu entries\n", num_available_asids); + + /* + * There must always be an ASID available after rollover. Ensure that, + * even if all CPUs have a reserved ASID and the maximum number of ASIDs + * are pinned, there still is at least one empty slot in the ASID map. + */ + max_pinned_asids = num_available_asids - num_possible_cpus() - 2; return 0; } arch_initcall(asids_update_limit); @@ -319,13 +408,17 @@ static int asids_init(void) panic("Failed to allocate bitmap for %lu ASIDs\n", NUM_USER_ASIDS); + pinned_asid_map = kcalloc(BITS_TO_LONGS(NUM_USER_ASIDS), + sizeof(*pinned_asid_map), GFP_KERNEL); + nr_pinned_asids = 0; + /* * We cannot call set_reserved_asid_bits() here because CPU * caps are not finalized yet, so it is safer to assume KPTI * and reserve kernel ASID's from beginning. */ if (IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) - set_kpti_asid_bits(); + set_kpti_asid_bits(asid_map); return 0; } early_initcall(asids_init); diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c index 2ee7b73433a5..70a71f38b6a9 100644 --- a/arch/arm64/mm/copypage.c +++ b/arch/arm64/mm/copypage.c @@ -6,21 +6,32 @@ * Copyright (C) 2012 ARM Ltd. */ +#include <linux/bitops.h> #include <linux/mm.h> #include <asm/page.h> #include <asm/cacheflush.h> +#include <asm/cpufeature.h> +#include <asm/mte.h> -void __cpu_copy_user_page(void *kto, const void *kfrom, unsigned long vaddr) +void copy_highpage(struct page *to, struct page *from) { - struct page *page = virt_to_page(kto); + struct page *kto = page_address(to); + struct page *kfrom = page_address(from); + copy_page(kto, kfrom); - flush_dcache_page(page); + + if (system_supports_mte() && test_bit(PG_mte_tagged, &from->flags)) { + set_bit(PG_mte_tagged, &to->flags); + mte_copy_page_tags(kto, kfrom); + } } -EXPORT_SYMBOL_GPL(__cpu_copy_user_page); +EXPORT_SYMBOL(copy_highpage); -void __cpu_clear_user_page(void *kaddr, unsigned long vaddr) +void copy_user_highpage(struct page *to, struct page *from, + unsigned long vaddr, struct vm_area_struct *vma) { - clear_page(kaddr); + copy_highpage(to, from); + flush_dcache_page(to); } -EXPORT_SYMBOL_GPL(__cpu_clear_user_page); +EXPORT_SYMBOL_GPL(copy_user_highpage); diff --git a/arch/arm64/mm/extable.c b/arch/arm64/mm/extable.c index eee1732ab6cd..aa0060178343 100644 --- a/arch/arm64/mm/extable.c +++ b/arch/arm64/mm/extable.c @@ -14,9 +14,7 @@ int fixup_exception(struct pt_regs *regs) if (!fixup) return 0; - if (IS_ENABLED(CONFIG_BPF_JIT) && - regs->pc >= BPF_JIT_REGION_START && - regs->pc < BPF_JIT_REGION_END) + if (in_bpf_jit(regs)) return arm64_bpf_fixup_exception(fixup, regs); regs->pc = (unsigned long)&fixup->fixup + fixup->fixup; diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index f07333e86c2f..94c99c1c19e3 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -218,7 +218,9 @@ int ptep_set_access_flags(struct vm_area_struct *vma, pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval); } while (pteval != old_pteval); - flush_tlb_fix_spurious_fault(vma, address); + /* Invalidate a stale read-only entry */ + if (dirty) + flush_tlb_page(vma, address); return 1; } @@ -641,6 +643,13 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs) return 0; } +static int do_tag_check_fault(unsigned long addr, unsigned int esr, + struct pt_regs *regs) +{ + do_bad_area(addr, esr, regs); + return 0; +} + static const struct fault_info fault_info[] = { { do_bad, SIGKILL, SI_KERNEL, "ttbr address size fault" }, { do_bad, SIGKILL, SI_KERNEL, "level 1 address size fault" }, @@ -659,7 +668,7 @@ static const struct fault_info fault_info[] = { { do_page_fault, SIGSEGV, SEGV_ACCERR, "level 2 permission fault" }, { do_page_fault, SIGSEGV, SEGV_ACCERR, "level 3 permission fault" }, { do_sea, SIGBUS, BUS_OBJERR, "synchronous external abort" }, - { do_bad, SIGKILL, SI_KERNEL, "unknown 17" }, + { do_tag_check_fault, SIGSEGV, SEGV_MTESERR, "synchronous tag check fault" }, { do_bad, SIGKILL, SI_KERNEL, "unknown 18" }, { do_bad, SIGKILL, SI_KERNEL, "unknown 19" }, { do_sea, SIGKILL, SI_KERNEL, "level 0 (translation table walk)" }, diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 75df62fea1b6..936c4762dadf 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -122,7 +122,7 @@ static bool pgattr_change_is_safe(u64 old, u64 new) * The following mapping attributes may be updated in live * kernel mappings without the need for break-before-make. */ - static const pteval_t mask = PTE_PXN | PTE_RDONLY | PTE_WRITE | PTE_NG; + pteval_t mask = PTE_PXN | PTE_RDONLY | PTE_WRITE | PTE_NG; /* creating or taking down mappings is always safe */ if (old == 0 || new == 0) @@ -136,6 +136,17 @@ static bool pgattr_change_is_safe(u64 old, u64 new) if (old & ~new & PTE_NG) return false; + /* + * Changing the memory type between Normal and Normal-Tagged is safe + * since Tagged is considered a permission attribute from the + * mismatched attribute aliases perspective. + */ + if (((old & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL) || + (old & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL_TAGGED)) && + ((new & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL) || + (new & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL_TAGGED))) + mask |= PTE_ATTRINDX_MASK; + return ((old ^ new) & ~mask) == 0; } @@ -491,7 +502,12 @@ static void __init map_mem(pgd_t *pgdp) if (memblock_is_nomap(reg)) continue; - __map_memblock(pgdp, start, end, PAGE_KERNEL, flags); + /* + * The linear map must allow allocation tags reading/writing + * if MTE is present. Otherwise, it has the same attributes as + * PAGE_KERNEL. + */ + __map_memblock(pgdp, start, end, PAGE_KERNEL_TAGGED, flags); } /* diff --git a/arch/arm64/mm/mteswap.c b/arch/arm64/mm/mteswap.c new file mode 100644 index 000000000000..c52c1847079c --- /dev/null +++ b/arch/arm64/mm/mteswap.c @@ -0,0 +1,83 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <linux/pagemap.h> +#include <linux/xarray.h> +#include <linux/slab.h> +#include <linux/swap.h> +#include <linux/swapops.h> +#include <asm/mte.h> + +static DEFINE_XARRAY(mte_pages); + +void *mte_allocate_tag_storage(void) +{ + /* tags granule is 16 bytes, 2 tags stored per byte */ + return kmalloc(PAGE_SIZE / 16 / 2, GFP_KERNEL); +} + +void mte_free_tag_storage(char *storage) +{ + kfree(storage); +} + +int mte_save_tags(struct page *page) +{ + void *tag_storage, *ret; + + if (!test_bit(PG_mte_tagged, &page->flags)) + return 0; + + tag_storage = mte_allocate_tag_storage(); + if (!tag_storage) + return -ENOMEM; + + mte_save_page_tags(page_address(page), tag_storage); + + /* page_private contains the swap entry.val set in do_swap_page */ + ret = xa_store(&mte_pages, page_private(page), tag_storage, GFP_KERNEL); + if (WARN(xa_is_err(ret), "Failed to store MTE tags")) { + mte_free_tag_storage(tag_storage); + return xa_err(ret); + } else if (ret) { + /* Entry is being replaced, free the old entry */ + mte_free_tag_storage(ret); + } + + return 0; +} + +bool mte_restore_tags(swp_entry_t entry, struct page *page) +{ + void *tags = xa_load(&mte_pages, entry.val); + + if (!tags) + return false; + + mte_restore_page_tags(page_address(page), tags); + + return true; +} + +void mte_invalidate_tags(int type, pgoff_t offset) +{ + swp_entry_t entry = swp_entry(type, offset); + void *tags = xa_erase(&mte_pages, entry.val); + + mte_free_tag_storage(tags); +} + +void mte_invalidate_tags_area(int type) +{ + swp_entry_t entry = swp_entry(type, 0); + swp_entry_t last_entry = swp_entry(type + 1, 0); + void *tags; + + XA_STATE(xa_state, &mte_pages, entry.val); + + xa_lock(&mte_pages); + xas_for_each(&xa_state, tags, last_entry.val - 1) { + __xa_erase(&mte_pages, xa_state.xa_index); + mte_free_tag_storage(tags); + } + xa_unlock(&mte_pages); +} diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c index 73f8b49d485c..676deb220b99 100644 --- a/arch/arm64/mm/numa.c +++ b/arch/arm64/mm/numa.c @@ -46,7 +46,11 @@ EXPORT_SYMBOL(node_to_cpumask_map); */ const struct cpumask *cpumask_of_node(int node) { - if (WARN_ON(node >= nr_node_ids)) + + if (node == NUMA_NO_NODE) + return cpu_all_mask; + + if (WARN_ON(node < 0 || node >= nr_node_ids)) return cpu_none_mask; if (WARN_ON(node_to_cpumask_map[node] == NULL)) @@ -448,7 +452,7 @@ static int __init dummy_numa_init(void) * arm64_numa_init() - Initialize NUMA * * Try each configured NUMA initialization method until one succeeds. The - * last fallback is dummy single node config encomapssing whole memory. + * last fallback is dummy single node config encompassing whole memory. */ void __init arm64_numa_init(void) { diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 23f648c2a199..1b94f5b82654 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -8,6 +8,7 @@ #include <linux/sched.h> #include <linux/vmalloc.h> +#include <asm/cacheflush.h> #include <asm/set_memory.h> #include <asm/tlbflush.h> diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 796e47a571e6..23c326a06b2d 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -18,6 +18,7 @@ #include <asm/cpufeature.h> #include <asm/alternative.h> #include <asm/smp.h> +#include <asm/sysreg.h> #ifdef CONFIG_ARM64_64K_PAGES #define TCR_TG_FLAGS TCR_TG0_64K | TCR_TG1_64K @@ -44,14 +45,18 @@ #define TCR_KASAN_FLAGS 0 #endif -/* Default MAIR_EL1 */ +/* + * Default MAIR_EL1. MT_NORMAL_TAGGED is initially mapped as Normal memory and + * changed during __cpu_setup to Normal Tagged if the system supports MTE. + */ #define MAIR_EL1_SET \ (MAIR_ATTRIDX(MAIR_ATTR_DEVICE_nGnRnE, MT_DEVICE_nGnRnE) | \ MAIR_ATTRIDX(MAIR_ATTR_DEVICE_nGnRE, MT_DEVICE_nGnRE) | \ MAIR_ATTRIDX(MAIR_ATTR_DEVICE_GRE, MT_DEVICE_GRE) | \ MAIR_ATTRIDX(MAIR_ATTR_NORMAL_NC, MT_NORMAL_NC) | \ MAIR_ATTRIDX(MAIR_ATTR_NORMAL, MT_NORMAL) | \ - MAIR_ATTRIDX(MAIR_ATTR_NORMAL_WT, MT_NORMAL_WT)) + MAIR_ATTRIDX(MAIR_ATTR_NORMAL_WT, MT_NORMAL_WT) | \ + MAIR_ATTRIDX(MAIR_ATTR_NORMAL, MT_NORMAL_TAGGED)) #ifdef CONFIG_CPU_PM /** @@ -421,6 +426,29 @@ SYM_FUNC_START(__cpu_setup) * Memory region attributes */ mov_q x5, MAIR_EL1_SET +#ifdef CONFIG_ARM64_MTE + /* + * Update MAIR_EL1, GCR_EL1 and TFSR*_EL1 if MTE is supported + * (ID_AA64PFR1_EL1[11:8] > 1). + */ + mrs x10, ID_AA64PFR1_EL1 + ubfx x10, x10, #ID_AA64PFR1_MTE_SHIFT, #4 + cmp x10, #ID_AA64PFR1_MTE + b.lt 1f + + /* Normal Tagged memory type at the corresponding MAIR index */ + mov x10, #MAIR_ATTR_NORMAL_TAGGED + bfi x5, x10, #(8 * MT_NORMAL_TAGGED), #8 + + /* initialize GCR_EL1: all non-zero tags excluded by default */ + mov x10, #(SYS_GCR_EL1_RRND | SYS_GCR_EL1_EXCL_MASK) + msr_s SYS_GCR_EL1, x10 + + /* clear any pending tag check faults in TFSR*_EL1 */ + msr_s SYS_TFSR_EL1, xzr + msr_s SYS_TFSRE0_EL1, xzr +1: +#endif msr mair_el1, x5 /* * Set/prepare TCR and TTBR. We use 512GB (39-bit) address range for diff --git a/arch/arm64/mm/dump.c b/arch/arm64/mm/ptdump.c index 0b8da1cc1c07..807dc634bbd2 100644 --- a/arch/arm64/mm/dump.c +++ b/arch/arm64/mm/ptdump.c @@ -41,6 +41,8 @@ static struct addr_marker address_markers[] = { { 0 /* KASAN_SHADOW_START */, "Kasan shadow start" }, { KASAN_SHADOW_END, "Kasan shadow end" }, #endif + { BPF_JIT_REGION_START, "BPF start" }, + { BPF_JIT_REGION_END, "BPF end" }, { MODULES_VADDR, "Modules start" }, { MODULES_END, "Modules end" }, { VMALLOC_START, "vmalloc() area" }, @@ -169,6 +171,10 @@ static const struct prot_bits pte_bits[] = { .mask = PTE_ATTRINDX_MASK, .val = PTE_ATTRINDX(MT_NORMAL), .set = "MEM/NORMAL", + }, { + .mask = PTE_ATTRINDX_MASK, + .val = PTE_ATTRINDX(MT_NORMAL_TAGGED), + .set = "MEM/NORMAL-TAGGED", } }; |