diff options
Diffstat (limited to 'arch/arm64/mm')
| -rw-r--r-- | arch/arm64/mm/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm64/mm/context.c | 105 | ||||
| -rw-r--r-- | arch/arm64/mm/extable.c | 4 | ||||
| -rw-r--r-- | arch/arm64/mm/fault.c | 4 | ||||
| -rw-r--r-- | arch/arm64/mm/numa.c | 2 | ||||
| -rw-r--r-- | arch/arm64/mm/ptdump.c (renamed from arch/arm64/mm/dump.c) | 2 |
6 files changed, 107 insertions, 12 deletions
diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile index d91030f0ffee..2a1d275cd4d7 100644 --- a/arch/arm64/mm/Makefile +++ b/arch/arm64/mm/Makefile @@ -4,7 +4,7 @@ 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 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/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..a696a7921da4 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; } diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c index 88e51aade0da..676deb220b99 100644 --- a/arch/arm64/mm/numa.c +++ b/arch/arm64/mm/numa.c @@ -452,7 +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/dump.c b/arch/arm64/mm/ptdump.c index 0b8da1cc1c07..265284dc942d 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" }, |