diff options
Diffstat (limited to 'arch/arm64/mm')
-rw-r--r-- | arch/arm64/mm/Makefile | 5 | ||||
-rw-r--r-- | arch/arm64/mm/context.c | 4 | ||||
-rw-r--r-- | arch/arm64/mm/contpte.c | 37 | ||||
-rw-r--r-- | arch/arm64/mm/copypage.c | 29 | ||||
-rw-r--r-- | arch/arm64/mm/dma-mapping.c | 13 | ||||
-rw-r--r-- | arch/arm64/mm/extable.c | 40 | ||||
-rw-r--r-- | arch/arm64/mm/fault.c | 143 | ||||
-rw-r--r-- | arch/arm64/mm/fixmap.c | 9 | ||||
-rw-r--r-- | arch/arm64/mm/gcs.c | 254 | ||||
-rw-r--r-- | arch/arm64/mm/hugetlbpage.c | 194 | ||||
-rw-r--r-- | arch/arm64/mm/init.c | 240 | ||||
-rw-r--r-- | arch/arm64/mm/ioremap.c | 24 | ||||
-rw-r--r-- | arch/arm64/mm/kasan_init.c | 6 | ||||
-rw-r--r-- | arch/arm64/mm/mem_encrypt.c | 50 | ||||
-rw-r--r-- | arch/arm64/mm/mmap.c | 20 | ||||
-rw-r--r-- | arch/arm64/mm/mmu.c | 262 | ||||
-rw-r--r-- | arch/arm64/mm/mteswap.c | 45 | ||||
-rw-r--r-- | arch/arm64/mm/pageattr.c | 123 | ||||
-rw-r--r-- | arch/arm64/mm/pgd.c | 4 | ||||
-rw-r--r-- | arch/arm64/mm/physaddr.c | 2 | ||||
-rw-r--r-- | arch/arm64/mm/proc.S | 51 | ||||
-rw-r--r-- | arch/arm64/mm/ptdump.c | 126 | ||||
-rw-r--r-- | arch/arm64/mm/trans_pgd.c | 15 |
23 files changed, 1276 insertions, 420 deletions
diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile index 60454256945b..c26489cf96cd 100644 --- a/arch/arm64/mm/Makefile +++ b/arch/arm64/mm/Makefile @@ -1,16 +1,17 @@ # SPDX-License-Identifier: GPL-2.0 obj-y := dma-mapping.o extable.o fault.o init.o \ cache.o copypage.o flush.o \ - ioremap.o mmap.o pgd.o mmu.o \ + ioremap.o mmap.o pgd.o mem_encrypt.o mmu.o \ context.o proc.o pageattr.o fixmap.o obj-$(CONFIG_ARM64_CONTPTE) += contpte.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o -obj-$(CONFIG_PTDUMP_CORE) += ptdump.o +obj-$(CONFIG_PTDUMP) += ptdump.o obj-$(CONFIG_PTDUMP_DEBUGFS) += ptdump_debugfs.o obj-$(CONFIG_TRANS_TABLE) += trans_pgd.o obj-$(CONFIG_TRANS_TABLE) += trans_pgd-asm.o obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o obj-$(CONFIG_ARM64_MTE) += mteswap.o +obj-$(CONFIG_ARM64_GCS) += gcs.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 188197590fc9..b2ac06246327 100644 --- a/arch/arm64/mm/context.c +++ b/arch/arm64/mm/context.c @@ -32,9 +32,9 @@ 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) +#define ASID_FIRST_VERSION (1UL << 16) -#define NUM_USER_ASIDS ASID_FIRST_VERSION +#define NUM_USER_ASIDS (1UL << asid_bits) #define ctxid2asid(asid) ((asid) & ~ASID_MASK) #define asid2ctxid(asid, genid) ((asid) | (genid)) diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c index 1b64b4c3f8bf..bcac4f55f9c1 100644 --- a/arch/arm64/mm/contpte.c +++ b/arch/arm64/mm/contpte.c @@ -335,7 +335,7 @@ int contpte_ptep_clear_flush_young(struct vm_area_struct *vma, * eliding the trailing DSB applies here. */ addr = ALIGN_DOWN(addr, CONT_PTE_SIZE); - __flush_tlb_range_nosync(vma, addr, addr + CONT_PTE_SIZE, + __flush_tlb_range_nosync(vma->vm_mm, addr, addr + CONT_PTE_SIZE, PAGE_SIZE, true, 3); } @@ -361,6 +361,35 @@ void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr, } EXPORT_SYMBOL_GPL(contpte_wrprotect_ptes); +void contpte_clear_young_dirty_ptes(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep, + unsigned int nr, cydp_t flags) +{ + /* + * We can safely clear access/dirty without needing to unfold from + * the architectures perspective, even when contpte is set. If the + * range starts or ends midway through a contpte block, we can just + * expand to include the full contpte block. While this is not + * exactly what the core-mm asked for, it tracks access/dirty per + * folio, not per page. And since we only create a contpte block + * when it is covered by a single folio, we can get away with + * clearing access/dirty for the whole block. + */ + unsigned long start = addr; + unsigned long end = start + nr * PAGE_SIZE; + + if (pte_cont(__ptep_get(ptep + nr - 1))) + end = ALIGN(end, CONT_PTE_SIZE); + + if (pte_cont(__ptep_get(ptep))) { + start = ALIGN_DOWN(start, CONT_PTE_SIZE); + ptep = contpte_align_down(ptep); + } + + __clear_young_dirty_ptes(vma, start, ptep, (end - start) / PAGE_SIZE, flags); +} +EXPORT_SYMBOL_GPL(contpte_clear_young_dirty_ptes); + int contpte_ptep_set_access_flags(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t entry, int dirty) @@ -392,6 +421,12 @@ int contpte_ptep_set_access_flags(struct vm_area_struct *vma, ptep = contpte_align_down(ptep); start_addr = addr = ALIGN_DOWN(addr, CONT_PTE_SIZE); + /* + * We are not advancing entry because __ptep_set_access_flags() + * only consumes access flags from entry. And since we have checked + * for the whole contpte block and returned early, pte_same() + * within __ptep_set_access_flags() is likely false. + */ for (i = 0; i < CONT_PTES; i++, ptep++, addr += PAGE_SIZE) __ptep_set_access_flags(vma, addr, ptep, entry, 0); diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c index a7bb20055ce0..a86c897017df 100644 --- a/arch/arm64/mm/copypage.c +++ b/arch/arm64/mm/copypage.c @@ -18,15 +18,42 @@ void copy_highpage(struct page *to, struct page *from) { void *kto = page_address(to); void *kfrom = page_address(from); + struct folio *src = page_folio(from); + struct folio *dst = page_folio(to); + unsigned int i, nr_pages; copy_page(kto, kfrom); if (kasan_hw_tags_enabled()) page_kasan_tag_reset(to); - if (system_supports_mte() && page_mte_tagged(from)) { + if (!system_supports_mte()) + return; + + if (folio_test_hugetlb(src)) { + if (!folio_test_hugetlb_mte_tagged(src) || + from != folio_page(src, 0)) + return; + + WARN_ON_ONCE(!folio_try_hugetlb_mte_tagging(dst)); + + /* + * Populate tags for all subpages. + * + * Don't assume the first page is head page since + * huge page copy may start from any subpage. + */ + nr_pages = folio_nr_pages(src); + for (i = 0; i < nr_pages; i++) { + kfrom = page_address(folio_page(src, i)); + kto = page_address(folio_page(dst, i)); + mte_copy_page_tags(kto, kfrom); + } + folio_set_hugetlb_mte_tagged(dst); + } else if (page_mte_tagged(from)) { /* It's a new page, shouldn't have been tagged yet */ WARN_ON_ONCE(!try_page_mte_tagging(to)); + mte_copy_page_tags(kto, kfrom); set_page_mte_tagged(to); } diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c index 61886e43e3a1..b2b5792b2caa 100644 --- a/arch/arm64/mm/dma-mapping.c +++ b/arch/arm64/mm/dma-mapping.c @@ -7,7 +7,6 @@ #include <linux/gfp.h> #include <linux/cache.h> #include <linux/dma-map-ops.h> -#include <linux/iommu.h> #include <xen/xen.h> #include <asm/cacheflush.h> @@ -39,15 +38,7 @@ void arch_dma_prep_coherent(struct page *page, size_t size) dcache_clean_poc(start, start + size); } -#ifdef CONFIG_IOMMU_DMA -void arch_teardown_dma_ops(struct device *dev) -{ - dev->dma_ops = NULL; -} -#endif - -void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, - bool coherent) +void arch_setup_dma_ops(struct device *dev, bool coherent) { int cls = cache_line_size_of_cpu(); @@ -58,8 +49,6 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, ARCH_DMA_MINALIGN, cls); dev->dma_coherent = coherent; - if (device_iommu_mapped(dev)) - iommu_setup_dma_ops(dev, dma_base, dma_base + size - 1); xen_setup_dma_ops(dev); } diff --git a/arch/arm64/mm/extable.c b/arch/arm64/mm/extable.c index 228d681a8715..6e0528831cd3 100644 --- a/arch/arm64/mm/extable.c +++ b/arch/arm64/mm/extable.c @@ -8,8 +8,33 @@ #include <linux/uaccess.h> #include <asm/asm-extable.h> +#include <asm/esr.h> #include <asm/ptrace.h> +static bool cpy_faulted_on_uaccess(const struct exception_table_entry *ex, + unsigned long esr) +{ + bool uaccess_is_write = FIELD_GET(EX_DATA_UACCESS_WRITE, ex->data); + bool fault_on_write = esr & ESR_ELx_WNR; + + return uaccess_is_write == fault_on_write; +} + +bool insn_may_access_user(unsigned long addr, unsigned long esr) +{ + const struct exception_table_entry *ex = search_exception_tables(addr); + + if (!ex) + return false; + + switch (ex->type) { + case EX_TYPE_UACCESS_CPY: + return cpy_faulted_on_uaccess(ex, esr); + default: + return true; + } +} + static inline unsigned long get_ex_fixup(const struct exception_table_entry *ex) { @@ -29,6 +54,17 @@ static bool ex_handler_uaccess_err_zero(const struct exception_table_entry *ex, return true; } +static bool ex_handler_uaccess_cpy(const struct exception_table_entry *ex, + struct pt_regs *regs, unsigned long esr) +{ + /* Do not fix up faults on kernel memory accesses */ + if (!cpy_faulted_on_uaccess(ex, esr)) + return false; + + regs->pc = get_ex_fixup(ex); + return true; +} + static bool ex_handler_load_unaligned_zeropad(const struct exception_table_entry *ex, struct pt_regs *regs) @@ -56,7 +92,7 @@ ex_handler_load_unaligned_zeropad(const struct exception_table_entry *ex, return true; } -bool fixup_exception(struct pt_regs *regs) +bool fixup_exception(struct pt_regs *regs, unsigned long esr) { const struct exception_table_entry *ex; @@ -70,6 +106,8 @@ bool fixup_exception(struct pt_regs *regs) case EX_TYPE_UACCESS_ERR_ZERO: case EX_TYPE_KACCESS_ERR_ZERO: return ex_handler_uaccess_err_zero(ex, regs); + case EX_TYPE_UACCESS_CPY: + return ex_handler_uaccess_cpy(ex, regs, esr); case EX_TYPE_LOAD_UNALIGNED_ZEROPAD: return ex_handler_load_unaligned_zeropad(ex, regs); } diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 8251e2fea9c7..ec0a337891dd 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -23,6 +23,7 @@ #include <linux/sched/debug.h> #include <linux/highmem.h> #include <linux/perf_event.h> +#include <linux/pkeys.h> #include <linux/preempt.h> #include <linux/hugetlb.h> @@ -374,7 +375,7 @@ static void __do_kernel_fault(unsigned long addr, unsigned long esr, * Are we prepared to handle this kernel fault? * We are almost certainly not prepared to handle instruction faults. */ - if (!is_el1_instruction_abort(esr) && fixup_exception(regs)) + if (!is_el1_instruction_abort(esr) && fixup_exception(regs, esr)) return; if (WARN_RATELIMIT(is_spurious_el1_translation_fault(addr, esr, regs), @@ -486,23 +487,29 @@ static void do_bad_area(unsigned long far, unsigned long esr, } } -#define VM_FAULT_BADMAP ((__force vm_fault_t)0x010000) -#define VM_FAULT_BADACCESS ((__force vm_fault_t)0x020000) +static bool fault_from_pkey(unsigned long esr, struct vm_area_struct *vma, + unsigned int mm_flags) +{ + unsigned long iss2 = ESR_ELx_ISS2(esr); + + if (!system_supports_poe()) + return false; + + if (esr_fsc_is_permission_fault(esr) && (iss2 & ESR_ELx_Overlay)) + return true; -static vm_fault_t __do_page_fault(struct mm_struct *mm, - struct vm_area_struct *vma, unsigned long addr, - unsigned int mm_flags, unsigned long vm_flags, - struct pt_regs *regs) + return !arch_vma_access_permitted(vma, + mm_flags & FAULT_FLAG_WRITE, + mm_flags & FAULT_FLAG_INSTRUCTION, + false); +} + +static bool is_gcs_fault(unsigned long esr) { - /* - * Ok, we have a good vm_area for this memory access, so we can handle - * it. - * Check that the permissions on the VMA allow for the fault which - * occurred. - */ - if (!(vma->vm_flags & vm_flags)) - return VM_FAULT_BADACCESS; - return handle_mm_fault(vma, addr, mm_flags, regs); + if (!esr_is_data_abort(esr)) + return false; + + return ESR_ELx_ISS2(esr) & ESR_ELx_GCS; } static bool is_el0_instruction_abort(unsigned long esr) @@ -519,6 +526,23 @@ static bool is_write_abort(unsigned long esr) return (esr & ESR_ELx_WNR) && !(esr & ESR_ELx_CM); } +static bool is_invalid_gcs_access(struct vm_area_struct *vma, u64 esr) +{ + if (!system_supports_gcs()) + return false; + + if (unlikely(is_gcs_fault(esr))) { + /* GCS accesses must be performed on a GCS page */ + if (!(vma->vm_flags & VM_SHADOW_STACK)) + return true; + } else if (unlikely(vma->vm_flags & VM_SHADOW_STACK)) { + /* Only GCS operations can write to a GCS page */ + return esr_is_data_abort(esr) && is_write_abort(esr); + } + + return false; +} + static int __kprobes do_page_fault(unsigned long far, unsigned long esr, struct pt_regs *regs) { @@ -529,6 +553,8 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, unsigned int mm_flags = FAULT_FLAG_DEFAULT; unsigned long addr = untagged_addr(far); struct vm_area_struct *vma; + int si_code; + int pkey = -1; if (kprobe_page_fault(regs, esr)) return 0; @@ -553,6 +579,14 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, /* It was exec fault */ vm_flags = VM_EXEC; mm_flags |= FAULT_FLAG_INSTRUCTION; + } else if (is_gcs_fault(esr)) { + /* + * The GCS permission on a page implies both read and + * write so always handle any GCS fault as a write fault, + * we need to trigger CoW even for GCS reads. + */ + vm_flags = VM_WRITE; + mm_flags |= FAULT_FLAG_WRITE; } else if (is_write_abort(esr)) { /* It was write fault */ vm_flags = VM_WRITE; @@ -572,7 +606,7 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, die_kernel_fault("execution of user memory", addr, esr, regs); - if (!search_exception_tables(regs->pc)) + if (!insn_may_access_user(regs->pc, esr)) die_kernel_fault("access to user memory outside uaccess routines", addr, esr, regs); } @@ -586,10 +620,30 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, if (!vma) goto lock_mmap; + if (is_invalid_gcs_access(vma, esr)) { + vma_end_read(vma); + fault = 0; + si_code = SEGV_ACCERR; + goto bad_area; + } + if (!(vma->vm_flags & vm_flags)) { vma_end_read(vma); - goto lock_mmap; + fault = 0; + si_code = SEGV_ACCERR; + count_vm_vma_lock_event(VMA_LOCK_SUCCESS); + goto bad_area; + } + + if (fault_from_pkey(esr, vma, mm_flags)) { + pkey = vma_pkey(vma); + vma_end_read(vma); + fault = 0; + si_code = SEGV_PKUERR; + count_vm_vma_lock_event(VMA_LOCK_SUCCESS); + goto bad_area; } + fault = handle_mm_fault(vma, addr, mm_flags | FAULT_FLAG_VMA_LOCK, regs); if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED))) vma_end_read(vma); @@ -613,11 +667,27 @@ lock_mmap: retry: vma = lock_mm_and_find_vma(mm, addr, regs); if (unlikely(!vma)) { - fault = VM_FAULT_BADMAP; - goto done; + fault = 0; + si_code = SEGV_MAPERR; + goto bad_area; + } + + if (!(vma->vm_flags & vm_flags)) { + mmap_read_unlock(mm); + fault = 0; + si_code = SEGV_ACCERR; + goto bad_area; } - fault = __do_page_fault(mm, vma, addr, mm_flags, vm_flags, regs); + if (fault_from_pkey(esr, vma, mm_flags)) { + pkey = vma_pkey(vma); + mmap_read_unlock(mm); + fault = 0; + si_code = SEGV_PKUERR; + goto bad_area; + } + + fault = handle_mm_fault(vma, addr, mm_flags, regs); /* Quick path to respond to signals */ if (fault_signal_pending(fault, regs)) { @@ -637,13 +707,12 @@ retry: mmap_read_unlock(mm); done: - /* - * Handle the "normal" (no error) case first. - */ - if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP | - VM_FAULT_BADACCESS)))) + /* Handle the "normal" (no error) case first. */ + if (likely(!(fault & VM_FAULT_ERROR))) return 0; + si_code = SEGV_MAPERR; +bad_area: /* * If we are in kernel mode at this point, we have no context to * handle this fault with. @@ -679,12 +748,22 @@ done: arm64_force_sig_mceerr(BUS_MCEERR_AR, far, lsb, inf->name); } else { /* - * Something tried to access memory that isn't in our memory - * map. + * The pkey value that we return to userspace can be different + * from the pkey that caused the fault. + * + * 1. T1 : mprotect_key(foo, PAGE_SIZE, pkey=4); + * 2. T1 : set POR_EL0 to deny access to pkey=4, touches, page + * 3. T1 : faults... + * 4. T2: mprotect_key(foo, PAGE_SIZE, pkey=5); + * 5. T1 : enters fault handler, takes mmap_lock, etc... + * 6. T1 : reaches here, sees vma_pkey(vma)=5, when we really + * faulted on a pte with its pkey=4. */ - arm64_force_sig_fault(SIGSEGV, - fault == VM_FAULT_BADACCESS ? SEGV_ACCERR : SEGV_MAPERR, - far, inf->name); + /* Something tried to access memory that out of memory map */ + if (si_code == SEGV_PKUERR) + arm64_force_sig_fault_pkey(far, inf->name, pkey); + else + arm64_force_sig_fault(SIGSEGV, si_code, far, inf->name); } return 0; @@ -944,7 +1023,7 @@ struct folio *vma_alloc_zeroed_movable_folio(struct vm_area_struct *vma, if (vma->vm_flags & VM_MTE) flags |= __GFP_ZEROTAGS; - return vma_alloc_folio(flags, 0, vma, vaddr, false); + return vma_alloc_folio(flags, 0, vma, vaddr); } void tag_clear_highpage(struct page *page) diff --git a/arch/arm64/mm/fixmap.c b/arch/arm64/mm/fixmap.c index de1e09d986ad..c5c5425791da 100644 --- a/arch/arm64/mm/fixmap.c +++ b/arch/arm64/mm/fixmap.c @@ -47,7 +47,8 @@ static void __init early_fixmap_init_pte(pmd_t *pmdp, unsigned long addr) if (pmd_none(pmd)) { ptep = bm_pte[BM_PTE_TABLE_IDX(addr)]; - __pmd_populate(pmdp, __pa_symbol(ptep), PMD_TYPE_TABLE); + __pmd_populate(pmdp, __pa_symbol(ptep), + PMD_TYPE_TABLE | PMD_TABLE_AF); } } @@ -59,7 +60,8 @@ static void __init early_fixmap_init_pmd(pud_t *pudp, unsigned long addr, pmd_t *pmdp; if (pud_none(pud)) - __pud_populate(pudp, __pa_symbol(bm_pmd), PUD_TYPE_TABLE); + __pud_populate(pudp, __pa_symbol(bm_pmd), + PUD_TYPE_TABLE | PUD_TABLE_AF); pmdp = pmd_offset_kimg(pudp, addr); do { @@ -86,7 +88,8 @@ static void __init early_fixmap_init_pud(p4d_t *p4dp, unsigned long addr, } if (p4d_none(p4d)) - __p4d_populate(p4dp, __pa_symbol(bm_pud), P4D_TYPE_TABLE); + __p4d_populate(p4dp, __pa_symbol(bm_pud), + P4D_TYPE_TABLE | P4D_TABLE_AF); pudp = pud_offset_kimg(p4dp, addr); early_fixmap_init_pmd(pudp, addr, end); diff --git a/arch/arm64/mm/gcs.c b/arch/arm64/mm/gcs.c new file mode 100644 index 000000000000..5c46ec527b1c --- /dev/null +++ b/arch/arm64/mm/gcs.c @@ -0,0 +1,254 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <linux/mm.h> +#include <linux/mman.h> +#include <linux/syscalls.h> +#include <linux/types.h> + +#include <asm/cmpxchg.h> +#include <asm/cpufeature.h> +#include <asm/gcs.h> +#include <asm/page.h> + +static unsigned long alloc_gcs(unsigned long addr, unsigned long size) +{ + int flags = MAP_ANONYMOUS | MAP_PRIVATE; + struct mm_struct *mm = current->mm; + unsigned long mapped_addr, unused; + + if (addr) + flags |= MAP_FIXED_NOREPLACE; + + mmap_write_lock(mm); + mapped_addr = do_mmap(NULL, addr, size, PROT_READ, flags, + VM_SHADOW_STACK | VM_WRITE, 0, &unused, NULL); + mmap_write_unlock(mm); + + return mapped_addr; +} + +static unsigned long gcs_size(unsigned long size) +{ + if (size) + return PAGE_ALIGN(size); + + /* Allocate RLIMIT_STACK/2 with limits of PAGE_SIZE..2G */ + size = PAGE_ALIGN(min_t(unsigned long long, + rlimit(RLIMIT_STACK) / 2, SZ_2G)); + return max(PAGE_SIZE, size); +} + +unsigned long gcs_alloc_thread_stack(struct task_struct *tsk, + const struct kernel_clone_args *args) +{ + unsigned long addr, size; + + if (!system_supports_gcs()) + return 0; + + if (!task_gcs_el0_enabled(tsk)) + return 0; + + if ((args->flags & (CLONE_VFORK | CLONE_VM)) != CLONE_VM) { + tsk->thread.gcspr_el0 = read_sysreg_s(SYS_GCSPR_EL0); + return 0; + } + + size = args->stack_size / 2; + + size = gcs_size(size); + addr = alloc_gcs(0, size); + if (IS_ERR_VALUE(addr)) + return addr; + + tsk->thread.gcs_base = addr; + tsk->thread.gcs_size = size; + tsk->thread.gcspr_el0 = addr + size - sizeof(u64); + + return addr; +} + +SYSCALL_DEFINE3(map_shadow_stack, unsigned long, addr, unsigned long, size, unsigned int, flags) +{ + unsigned long alloc_size; + unsigned long __user *cap_ptr; + unsigned long cap_val; + int ret = 0; + int cap_offset; + + if (!system_supports_gcs()) + return -EOPNOTSUPP; + + if (flags & ~(SHADOW_STACK_SET_TOKEN | SHADOW_STACK_SET_MARKER)) + return -EINVAL; + + if (!PAGE_ALIGNED(addr)) + return -EINVAL; + + if (size == 8 || !IS_ALIGNED(size, 8)) + return -EINVAL; + + /* + * An overflow would result in attempting to write the restore token + * to the wrong location. Not catastrophic, but just return the right + * error code and block it. + */ + alloc_size = PAGE_ALIGN(size); + if (alloc_size < size) + return -EOVERFLOW; + + addr = alloc_gcs(addr, alloc_size); + if (IS_ERR_VALUE(addr)) + return addr; + + /* + * Put a cap token at the end of the allocated region so it + * can be switched to. + */ + if (flags & SHADOW_STACK_SET_TOKEN) { + /* Leave an extra empty frame as a top of stack marker? */ + if (flags & SHADOW_STACK_SET_MARKER) + cap_offset = 2; + else + cap_offset = 1; + + cap_ptr = (unsigned long __user *)(addr + size - + (cap_offset * sizeof(unsigned long))); + cap_val = GCS_CAP(cap_ptr); + + put_user_gcs(cap_val, cap_ptr, &ret); + if (ret != 0) { + vm_munmap(addr, size); + return -EFAULT; + } + + /* + * Ensure the new cap is ordered before standard + * memory accesses to the same location. + */ + gcsb_dsync(); + } + + return addr; +} + +/* + * Apply the GCS mode configured for the specified task to the + * hardware. + */ +void gcs_set_el0_mode(struct task_struct *task) +{ + u64 gcscre0_el1 = GCSCRE0_EL1_nTR; + + if (task->thread.gcs_el0_mode & PR_SHADOW_STACK_ENABLE) + gcscre0_el1 |= GCSCRE0_EL1_RVCHKEN | GCSCRE0_EL1_PCRSEL; + + if (task->thread.gcs_el0_mode & PR_SHADOW_STACK_WRITE) + gcscre0_el1 |= GCSCRE0_EL1_STREn; + + if (task->thread.gcs_el0_mode & PR_SHADOW_STACK_PUSH) + gcscre0_el1 |= GCSCRE0_EL1_PUSHMEn; + + write_sysreg_s(gcscre0_el1, SYS_GCSCRE0_EL1); +} + +void gcs_free(struct task_struct *task) +{ + if (!system_supports_gcs()) + return; + + /* + * When fork() with CLONE_VM fails, the child (tsk) already + * has a GCS allocated, and exit_thread() calls this function + * to free it. In this case the parent (current) and the + * child share the same mm struct. + */ + if (!task->mm || task->mm != current->mm) + return; + + if (task->thread.gcs_base) + vm_munmap(task->thread.gcs_base, task->thread.gcs_size); + + task->thread.gcspr_el0 = 0; + task->thread.gcs_base = 0; + task->thread.gcs_size = 0; +} + +int arch_set_shadow_stack_status(struct task_struct *task, unsigned long arg) +{ + unsigned long gcs, size; + int ret; + + if (!system_supports_gcs()) + return -EINVAL; + + if (is_compat_thread(task_thread_info(task))) + return -EINVAL; + + /* Reject unknown flags */ + if (arg & ~PR_SHADOW_STACK_SUPPORTED_STATUS_MASK) + return -EINVAL; + + ret = gcs_check_locked(task, arg); + if (ret != 0) + return ret; + + /* If we are enabling GCS then make sure we have a stack */ + if (arg & PR_SHADOW_STACK_ENABLE && + !task_gcs_el0_enabled(task)) { + /* Do not allow GCS to be reenabled */ + if (task->thread.gcs_base || task->thread.gcspr_el0) + return -EINVAL; + + if (task != current) + return -EBUSY; + + size = gcs_size(0); + gcs = alloc_gcs(0, size); + if (!gcs) + return -ENOMEM; + + task->thread.gcspr_el0 = gcs + size - sizeof(u64); + task->thread.gcs_base = gcs; + task->thread.gcs_size = size; + if (task == current) + write_sysreg_s(task->thread.gcspr_el0, + SYS_GCSPR_EL0); + } + + task->thread.gcs_el0_mode = arg; + if (task == current) + gcs_set_el0_mode(task); + + return 0; +} + +int arch_get_shadow_stack_status(struct task_struct *task, + unsigned long __user *arg) +{ + if (!system_supports_gcs()) + return -EINVAL; + + if (is_compat_thread(task_thread_info(task))) + return -EINVAL; + + return put_user(task->thread.gcs_el0_mode, arg); +} + +int arch_lock_shadow_stack_status(struct task_struct *task, + unsigned long arg) +{ + if (!system_supports_gcs()) + return -EINVAL; + + if (is_compat_thread(task_thread_info(task))) + return -EINVAL; + + /* + * We support locking unknown bits so applications can prevent + * any changes in a future proof manner. + */ + task->thread.gcs_el0_locked |= arg; + + return 0; +} diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 0f0e10bb0a95..0c8737f4f2ce 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -79,20 +79,6 @@ bool arch_hugetlb_migration_supported(struct hstate *h) } #endif -int pmd_huge(pmd_t pmd) -{ - return pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT); -} - -int pud_huge(pud_t pud) -{ -#ifndef __PAGETABLE_PMD_FOLDED - return pud_val(pud) && !(pud_val(pud) & PUD_TABLE_BIT); -#else - return 0; -#endif -} - static int find_num_contig(struct mm_struct *mm, unsigned long addr, pte_t *ptep, size_t *pgsize) { @@ -114,20 +100,11 @@ static int find_num_contig(struct mm_struct *mm, unsigned long addr, static inline int num_contig_ptes(unsigned long size, size_t *pgsize) { - int contig_ptes = 0; + int contig_ptes = 1; *pgsize = size; switch (size) { -#ifndef __PAGETABLE_PMD_FOLDED - case PUD_SIZE: - if (pud_sect_supported()) - contig_ptes = 1; - break; -#endif - case PMD_SIZE: - contig_ptes = 1; - break; case CONT_PMD_SIZE: *pgsize = PMD_SIZE; contig_ptes = CONT_PMDS; @@ -136,12 +113,14 @@ static inline int num_contig_ptes(unsigned long size, size_t *pgsize) *pgsize = PAGE_SIZE; contig_ptes = CONT_PTES; break; + default: + WARN_ON(!__hugetlb_valid_size(size)); } return contig_ptes; } -pte_t huge_ptep_get(pte_t *ptep) +pte_t huge_ptep_get(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { int ncontig, i; size_t pgsize; @@ -150,7 +129,7 @@ pte_t huge_ptep_get(pte_t *ptep) if (!pte_present(orig_pte) || !pte_cont(orig_pte)) return orig_pte; - ncontig = num_contig_ptes(page_size(pte_page(orig_pte)), &pgsize); + ncontig = find_num_contig(mm, addr, ptep, &pgsize); for (i = 0; i < ncontig; i++, ptep++) { pte_t pte = __ptep_get(ptep); @@ -177,24 +156,22 @@ static pte_t get_clear_contig(struct mm_struct *mm, unsigned long pgsize, unsigned long ncontig) { - pte_t orig_pte = __ptep_get(ptep); - unsigned long i; - - for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) { - pte_t pte = __ptep_get_and_clear(mm, addr, ptep); - - /* - * If HW_AFDBM is enabled, then the HW could turn on - * the dirty or accessed bit for any page in the set, - * so check them all. - */ - if (pte_dirty(pte)) - orig_pte = pte_mkdirty(orig_pte); - - if (pte_young(pte)) - orig_pte = pte_mkyoung(orig_pte); + pte_t pte, tmp_pte; + bool present; + + pte = __ptep_get_and_clear_anysz(mm, ptep, pgsize); + present = pte_present(pte); + while (--ncontig) { + ptep++; + tmp_pte = __ptep_get_and_clear_anysz(mm, ptep, pgsize); + if (present) { + if (pte_dirty(tmp_pte)) + pte = pte_mkdirty(pte); + if (pte_young(tmp_pte)) + pte = pte_mkyoung(pte); + } } - return orig_pte; + return pte; } static pte_t get_clear_contig_flush(struct mm_struct *mm, @@ -205,8 +182,9 @@ static pte_t get_clear_contig_flush(struct mm_struct *mm, { pte_t orig_pte = get_clear_contig(mm, addr, ptep, pgsize, ncontig); struct vm_area_struct vma = TLB_FLUSH_VMA(mm, 0); + unsigned long end = addr + (pgsize * ncontig); - flush_tlb_range(&vma, addr, addr + (pgsize * ncontig)); + __flush_hugetlb_tlb_range(&vma, addr, end, pgsize, true); return orig_pte; } @@ -229,9 +207,12 @@ static void clear_flush(struct mm_struct *mm, unsigned long i, saddr = addr; for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) - __ptep_get_and_clear(mm, addr, ptep); + __ptep_get_and_clear_anysz(mm, ptep, pgsize); - flush_tlb_range(&vma, saddr, addr); + if (mm == &init_mm) + flush_tlb_kernel_range(saddr, addr); + else + __flush_hugetlb_tlb_range(&vma, saddr, addr, pgsize, true); } void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, @@ -240,30 +221,20 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, size_t pgsize; int i; int ncontig; - unsigned long pfn, dpfn; - pgprot_t hugeprot; ncontig = num_contig_ptes(sz, &pgsize); if (!pte_present(pte)) { for (i = 0; i < ncontig; i++, ptep++, addr += pgsize) - __set_ptes(mm, addr, ptep, pte, 1); + __set_ptes_anysz(mm, ptep, pte, 1, pgsize); return; } - if (!pte_cont(pte)) { - __set_ptes(mm, addr, ptep, pte, 1); - return; - } - - pfn = pte_pfn(pte); - dpfn = pgsize >> PAGE_SHIFT; - hugeprot = pte_pgprot(pte); + /* Only need to "break" if transitioning valid -> valid. */ + if (pte_cont(pte) && pte_valid(__ptep_get(ptep))) + clear_flush(mm, addr, ptep, pgsize, ncontig); - clear_flush(mm, addr, ptep, pgsize, ncontig); - - for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) - __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1); + __set_ptes_anysz(mm, ptep, pte, ncontig, pgsize); } pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, @@ -276,7 +247,10 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, pte_t *ptep = NULL; pgdp = pgd_offset(mm, addr); - p4dp = p4d_offset(pgdp, addr); + p4dp = p4d_alloc(mm, pgdp, addr); + if (!p4dp) + return NULL; + pudp = pud_alloc(mm, p4dp, addr); if (!pudp) return NULL; @@ -325,7 +299,7 @@ pte_t *huge_pte_offset(struct mm_struct *mm, if (sz != PUD_SIZE && pud_none(pud)) return NULL; /* hugepage or swap? */ - if (pud_huge(pud) || !pud_present(pud)) + if (pud_leaf(pud) || !pud_present(pud)) return (pte_t *)pudp; /* table; check the next level */ @@ -337,7 +311,7 @@ pte_t *huge_pte_offset(struct mm_struct *mm, if (!(sz == PMD_SIZE || sz == CONT_PMD_SIZE) && pmd_none(pmd)) return NULL; - if (pmd_huge(pmd) || !pmd_present(pmd)) + if (pmd_leaf(pmd) || !pmd_present(pmd)) return (pte_t *)pmdp; if (sz == CONT_PTE_SIZE) @@ -353,7 +327,9 @@ unsigned long hugetlb_mask_last_page(struct hstate *h) switch (hp_size) { #ifndef __PAGETABLE_PMD_FOLDED case PUD_SIZE: - return PGDIR_SIZE - PUD_SIZE; + if (pud_sect_supported()) + return PGDIR_SIZE - PUD_SIZE; + break; #endif case CONT_PMD_SIZE: return PUD_SIZE - CONT_PMD_SIZE; @@ -372,15 +348,24 @@ pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags) { size_t pagesize = 1UL << shift; - entry = pte_mkhuge(entry); - if (pagesize == CONT_PTE_SIZE) { - entry = pte_mkcont(entry); - } else if (pagesize == CONT_PMD_SIZE) { - entry = pmd_pte(pmd_mkcont(pte_pmd(entry))); - } else if (pagesize != PUD_SIZE && pagesize != PMD_SIZE) { - pr_warn("%s: unrecognized huge page size 0x%lx\n", - __func__, pagesize); + switch (pagesize) { +#ifndef __PAGETABLE_PMD_FOLDED + case PUD_SIZE: + if (pud_sect_supported()) + return pud_pte(pud_mkhuge(pte_pud(entry))); + break; +#endif + case CONT_PMD_SIZE: + return pmd_pte(pmd_mkhuge(pmd_mkcont(pte_pmd(entry)))); + case PMD_SIZE: + return pmd_pte(pmd_mkhuge(pte_pmd(entry))); + case CONT_PTE_SIZE: + return pte_mkcont(entry); + default: + break; } + pr_warn("%s: unrecognized huge page size 0x%lx\n", + __func__, pagesize); return entry; } @@ -396,18 +381,13 @@ void huge_pte_clear(struct mm_struct *mm, unsigned long addr, __pte_clear(mm, addr, ptep); } -pte_t huge_ptep_get_and_clear(struct mm_struct *mm, - unsigned long addr, pte_t *ptep) +pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, unsigned long sz) { int ncontig; size_t pgsize; - pte_t orig_pte = __ptep_get(ptep); - - if (!pte_cont(orig_pte)) - return __ptep_get_and_clear(mm, addr, ptep); - - ncontig = find_num_contig(mm, addr, ptep, &pgsize); + ncontig = num_contig_ptes(sz, &pgsize); return get_clear_contig(mm, addr, ptep, pgsize, ncontig); } @@ -444,23 +424,23 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t pte, int dirty) { - int ncontig, i; + int ncontig; size_t pgsize = 0; - unsigned long pfn = pte_pfn(pte), dpfn; struct mm_struct *mm = vma->vm_mm; - pgprot_t hugeprot; pte_t orig_pte; + VM_WARN_ON(!pte_present(pte)); + if (!pte_cont(pte)) return __ptep_set_access_flags(vma, addr, ptep, pte, dirty); - ncontig = find_num_contig(mm, addr, ptep, &pgsize); - dpfn = pgsize >> PAGE_SHIFT; + ncontig = num_contig_ptes(huge_page_size(hstate_vma(vma)), &pgsize); if (!__cont_access_flags_changed(ptep, pte, ncontig)) return 0; orig_pte = get_clear_contig_flush(mm, addr, ptep, pgsize, ncontig); + VM_WARN_ON(!pte_present(orig_pte)); /* Make sure we don't lose the dirty or young state */ if (pte_dirty(orig_pte)) @@ -469,38 +449,31 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma, if (pte_young(orig_pte)) pte = pte_mkyoung(pte); - hugeprot = pte_pgprot(pte); - for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) - __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1); - + __set_ptes_anysz(mm, ptep, pte, ncontig, pgsize); return 1; } void huge_ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - unsigned long pfn, dpfn; - pgprot_t hugeprot; - int ncontig, i; + int ncontig; size_t pgsize; pte_t pte; - if (!pte_cont(__ptep_get(ptep))) { + pte = __ptep_get(ptep); + VM_WARN_ON(!pte_present(pte)); + + if (!pte_cont(pte)) { __ptep_set_wrprotect(mm, addr, ptep); return; } ncontig = find_num_contig(mm, addr, ptep, &pgsize); - dpfn = pgsize >> PAGE_SHIFT; pte = get_clear_contig_flush(mm, addr, ptep, pgsize, ncontig); pte = pte_wrprotect(pte); - hugeprot = pte_pgprot(pte); - pfn = pte_pfn(pte); - - for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) - __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1); + __set_ptes_anysz(mm, ptep, pte, ncontig, pgsize); } pte_t huge_ptep_clear_flush(struct vm_area_struct *vma, @@ -510,15 +483,24 @@ pte_t huge_ptep_clear_flush(struct vm_area_struct *vma, size_t pgsize; int ncontig; - if (!pte_cont(__ptep_get(ptep))) - return ptep_clear_flush(vma, addr, ptep); - - ncontig = find_num_contig(mm, addr, ptep, &pgsize); + ncontig = num_contig_ptes(huge_page_size(hstate_vma(vma)), &pgsize); return get_clear_contig_flush(mm, addr, ptep, pgsize, ncontig); } static int __init hugetlbpage_init(void) { + /* + * HugeTLB pages are supported on maximum four page table + * levels (PUD, CONT PMD, PMD, CONT PTE) for a given base + * page size, corresponding to hugetlb_add_hstate() calls + * here. + * + * HUGE_MAX_HSTATE should at least match maximum supported + * HugeTLB page sizes on the platform. Any new addition to + * supported HugeTLB page sizes will also require changing + * HUGE_MAX_HSTATE as well. + */ + BUILD_BUG_ON(HUGE_MAX_HSTATE < 4); if (pud_sect_supported()) hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT); @@ -537,6 +519,8 @@ bool __init arch_hugetlb_valid_size(unsigned long size) pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) { + unsigned long psize = huge_page_size(hstate_vma(vma)); + if (alternative_has_cap_unlikely(ARM64_WORKAROUND_2645198)) { /* * Break-before-make (BBM) is required for all user space mappings @@ -546,7 +530,7 @@ pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr if (pte_user_exec(__ptep_get(ptep))) return huge_ptep_clear_flush(vma, addr, ptep); } - return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep); + return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep, psize); } void huge_ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 03efd86dce0a..0c8c35dd645e 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -32,6 +32,7 @@ #include <linux/hugetlb.h> #include <linux/acpi_iort.h> #include <linux/kmemleak.h> +#include <linux/execmem.h> #include <asm/boot.h> #include <asm/fixmap.h> @@ -40,6 +41,7 @@ #include <asm/kvm_host.h> #include <asm/memory.h> #include <asm/numa.h> +#include <asm/rsi.h> #include <asm/sections.h> #include <asm/setup.h> #include <linux/sizes.h> @@ -96,53 +98,47 @@ static void __init arch_reserve_crashkernel(void) { unsigned long long low_size = 0; unsigned long long crash_base, crash_size; - char *cmdline = boot_command_line; bool high = false; int ret; if (!IS_ENABLED(CONFIG_CRASH_RESERVE)) return; - ret = parse_crashkernel(cmdline, memblock_phys_mem_size(), + ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), &crash_size, &crash_base, &low_size, &high); if (ret) return; - reserve_crashkernel_generic(cmdline, crash_size, crash_base, - low_size, high); + reserve_crashkernel_generic(crash_size, crash_base, low_size, high); } -/* - * Return the maximum physical address for a zone accessible by the given bits - * limit. If DRAM starts above 32-bit, expand the zone to the maximum - * available memory, otherwise cap it at 32-bit. - */ -static phys_addr_t __init max_zone_phys(unsigned int zone_bits) +static phys_addr_t __init max_zone_phys(phys_addr_t zone_limit) { - phys_addr_t zone_mask = DMA_BIT_MASK(zone_bits); - phys_addr_t phys_start = memblock_start_of_DRAM(); - - if (phys_start > U32_MAX) - zone_mask = PHYS_ADDR_MAX; - else if (phys_start > zone_mask) - zone_mask = U32_MAX; - - return min(zone_mask, memblock_end_of_DRAM() - 1) + 1; + return min(zone_limit, memblock_end_of_DRAM() - 1) + 1; } static void __init zone_sizes_init(void) { unsigned long max_zone_pfns[MAX_NR_ZONES] = {0}; - unsigned int __maybe_unused acpi_zone_dma_bits; - unsigned int __maybe_unused dt_zone_dma_bits; - phys_addr_t __maybe_unused dma32_phys_limit = max_zone_phys(32); + phys_addr_t __maybe_unused acpi_zone_dma_limit; + phys_addr_t __maybe_unused dt_zone_dma_limit; + phys_addr_t __maybe_unused dma32_phys_limit = + max_zone_phys(DMA_BIT_MASK(32)); #ifdef CONFIG_ZONE_DMA - acpi_zone_dma_bits = fls64(acpi_iort_dma_get_max_cpu_address()); - dt_zone_dma_bits = fls64(of_dma_get_max_cpu_address(NULL)); - zone_dma_bits = min3(32U, dt_zone_dma_bits, acpi_zone_dma_bits); - arm64_dma_phys_limit = max_zone_phys(zone_dma_bits); + acpi_zone_dma_limit = acpi_iort_dma_get_max_cpu_address(); + dt_zone_dma_limit = of_dma_get_max_cpu_address(NULL); + zone_dma_limit = min(dt_zone_dma_limit, acpi_zone_dma_limit); + /* + * Information we get from firmware (e.g. DT dma-ranges) describe DMA + * bus constraints. Devices using DMA might have their own limitations. + * Some of them rely on DMA zone in low 32-bit memory. Keep low RAM + * DMA zone on platforms that have RAM there. + */ + if (memblock_start_of_DRAM() < U32_MAX) + zone_dma_limit = min(zone_dma_limit, U32_MAX); + arm64_dma_phys_limit = max_zone_phys(zone_dma_limit); max_zone_pfns[ZONE_DMA] = PFN_DOWN(arm64_dma_phys_limit); #endif #ifdef CONFIG_ZONE_DMA32 @@ -279,26 +275,6 @@ void __init arm64_memblock_init(void) } } - if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) { - extern u16 memstart_offset_seed; - u64 mmfr0 = read_cpuid(ID_AA64MMFR0_EL1); - int parange = cpuid_feature_extract_unsigned_field( - mmfr0, ID_AA64MMFR0_EL1_PARANGE_SHIFT); - s64 range = linear_region_size - - BIT(id_aa64mmfr0_parange_to_phys_shift(parange)); - - /* - * If the size of the linear region exceeds, by a sufficient - * margin, the size of the region that the physical memory can - * span, randomize the linear region as well. - */ - if (memstart_offset_seed > 0 && range >= (s64)ARM64_MEMSTART_ALIGN) { - range /= ARM64_MEMSTART_ALIGN; - memstart_addr -= ARM64_MEMSTART_ALIGN * - ((range * memstart_offset_seed) >> 16); - } - } - /* * Register the kernel text, kernel data, initrd, and initial * pagetables with memblock. @@ -311,8 +287,6 @@ void __init arm64_memblock_init(void) } early_init_fdt_scan_reserved_mem(); - - high_memory = __va(memblock_end_of_DRAM() - 1) + 1; } void __init bootmem_init(void) @@ -361,15 +335,16 @@ void __init bootmem_init(void) memblock_dump_all(); } -/* - * mem_init() marks the free areas in the mem_map and tells us how much memory - * is free. This is done after various parts of the system have claimed their - * memory after the kernel image. - */ -void __init mem_init(void) +void __init arch_mm_preinit(void) { + unsigned int flags = SWIOTLB_VERBOSE; bool swiotlb = max_pfn > PFN_DOWN(arm64_dma_phys_limit); + if (is_realm_world()) { + swiotlb = true; + flags |= SWIOTLB_FORCE; + } + if (IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC) && !swiotlb) { /* * If no bouncing needed for ZONE_DMA, reduce the swiotlb @@ -381,10 +356,8 @@ void __init mem_init(void) swiotlb = true; } - swiotlb_init(swiotlb, SWIOTLB_VERBOSE); - - /* this will put all unused low memory onto the freelists */ - memblock_free_all(); + swiotlb_init(swiotlb, flags); + swiotlb_update_mem_attributes(); /* * Check boundaries twice: Some fundamental inconsistencies can be @@ -413,8 +386,16 @@ void __init mem_init(void) void free_initmem(void) { - free_reserved_area(lm_alias(__init_begin), - lm_alias(__init_end), + void *lm_init_begin = lm_alias(__init_begin); + void *lm_init_end = lm_alias(__init_end); + + WARN_ON(!IS_ALIGNED((unsigned long)lm_init_begin, PAGE_SIZE)); + WARN_ON(!IS_ALIGNED((unsigned long)lm_init_end, PAGE_SIZE)); + + /* Delete __init region from memblock.reserved. */ + memblock_free(lm_init_begin, lm_init_end - lm_init_begin); + + free_reserved_area(lm_init_begin, lm_init_end, POISON_FREE_INITMEM, "unused kernel"); /* * Unmap the __init region but leave the VM area in place. This @@ -432,3 +413,142 @@ void dump_mem_limit(void) pr_emerg("Memory Limit: none\n"); } } + +#ifdef CONFIG_EXECMEM +static u64 module_direct_base __ro_after_init = 0; +static u64 module_plt_base __ro_after_init = 0; + +/* + * Choose a random page-aligned base address for a window of 'size' bytes which + * entirely contains the interval [start, end - 1]. + */ +static u64 __init random_bounding_box(u64 size, u64 start, u64 end) +{ + u64 max_pgoff, pgoff; + + if ((end - start) >= size) + return 0; + + max_pgoff = (size - (end - start)) / PAGE_SIZE; + pgoff = get_random_u32_inclusive(0, max_pgoff); + + return start - pgoff * PAGE_SIZE; +} + +/* + * Modules may directly reference data and text anywhere within the kernel + * image and other modules. References using PREL32 relocations have a +/-2G + * range, and so we need to ensure that the entire kernel image and all modules + * fall within a 2G window such that these are always within range. + * + * Modules may directly branch to functions and code within the kernel text, + * and to functions and code within other modules. These branches will use + * CALL26/JUMP26 relocations with a +/-128M range. Without PLTs, we must ensure + * that the entire kernel text and all module text falls within a 128M window + * such that these are always within range. With PLTs, we can expand this to a + * 2G window. + * + * We chose the 128M region to surround the entire kernel image (rather than + * just the text) as using the same bounds for the 128M and 2G regions ensures + * by construction that we never select a 128M region that is not a subset of + * the 2G region. For very large and unusual kernel configurations this means + * we may fall back to PLTs where they could have been avoided, but this keeps + * the logic significantly simpler. + */ +static int __init module_init_limits(void) +{ + u64 kernel_end = (u64)_end; + u64 kernel_start = (u64)_text; + u64 kernel_size = kernel_end - kernel_start; + + /* + * The default modules region is placed immediately below the kernel + * image, and is large enough to use the full 2G relocation range. + */ + BUILD_BUG_ON(KIMAGE_VADDR != MODULES_END); + BUILD_BUG_ON(MODULES_VSIZE < SZ_2G); + + if (!kaslr_enabled()) { + if (kernel_size < SZ_128M) + module_direct_base = kernel_end - SZ_128M; + if (kernel_size < SZ_2G) + module_plt_base = kernel_end - SZ_2G; + } else { + u64 min = kernel_start; + u64 max = kernel_end; + + if (IS_ENABLED(CONFIG_RANDOMIZE_MODULE_REGION_FULL)) { + pr_info("2G module region forced by RANDOMIZE_MODULE_REGION_FULL\n"); + } else { + module_direct_base = random_bounding_box(SZ_128M, min, max); + if (module_direct_base) { + min = module_direct_base; + max = module_direct_base + SZ_128M; + } + } + + module_plt_base = random_bounding_box(SZ_2G, min, max); + } + + pr_info("%llu pages in range for non-PLT usage", + module_direct_base ? (SZ_128M - kernel_size) / PAGE_SIZE : 0); + pr_info("%llu pages in range for PLT usage", + module_plt_base ? (SZ_2G - kernel_size) / PAGE_SIZE : 0); + + return 0; +} + +static struct execmem_info execmem_info __ro_after_init; + +struct execmem_info __init *execmem_arch_setup(void) +{ + unsigned long fallback_start = 0, fallback_end = 0; + unsigned long start = 0, end = 0; + + module_init_limits(); + + /* + * Where possible, prefer to allocate within direct branch range of the + * kernel such that no PLTs are necessary. + */ + if (module_direct_base) { + start = module_direct_base; + end = module_direct_base + SZ_128M; + + if (module_plt_base) { + fallback_start = module_plt_base; + fallback_end = module_plt_base + SZ_2G; + } + } else if (module_plt_base) { + start = module_plt_base; + end = module_plt_base + SZ_2G; + } + + execmem_info = (struct execmem_info){ + .ranges = { + [EXECMEM_DEFAULT] = { + .start = start, + .end = end, + .pgprot = PAGE_KERNEL, + .alignment = 1, + .fallback_start = fallback_start, + .fallback_end = fallback_end, + }, + [EXECMEM_KPROBES] = { + .start = VMALLOC_START, + .end = VMALLOC_END, + .pgprot = PAGE_KERNEL_ROX, + .alignment = 1, + }, + [EXECMEM_BPF] = { + .start = VMALLOC_START, + .end = VMALLOC_END, + .pgprot = PAGE_KERNEL, + .alignment = 1, + }, + }, + }; + + return &execmem_info; +} +#endif /* CONFIG_EXECMEM */ diff --git a/arch/arm64/mm/ioremap.c b/arch/arm64/mm/ioremap.c index 269f2f63ab7d..10e246f11271 100644 --- a/arch/arm64/mm/ioremap.c +++ b/arch/arm64/mm/ioremap.c @@ -3,8 +3,19 @@ #include <linux/mm.h> #include <linux/io.h> +static ioremap_prot_hook_t ioremap_prot_hook; + +int arm64_ioremap_prot_hook_register(ioremap_prot_hook_t hook) +{ + if (WARN_ON(ioremap_prot_hook)) + return -EBUSY; + + ioremap_prot_hook = hook; + return 0; +} + void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size, - unsigned long prot) + pgprot_t pgprot) { unsigned long last_addr = phys_addr + size - 1; @@ -16,7 +27,16 @@ void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size, if (WARN_ON(pfn_is_map_memory(__phys_to_pfn(phys_addr)))) return NULL; - return generic_ioremap_prot(phys_addr, size, __pgprot(prot)); + /* + * If a hook is registered (e.g. for confidential computing + * purposes), call that now and barf if it fails. + */ + if (unlikely(ioremap_prot_hook) && + WARN_ON(ioremap_prot_hook(phys_addr, size, &pgprot))) { + return NULL; + } + + return generic_ioremap_prot(phys_addr, size, pgprot); } EXPORT_SYMBOL(ioremap_prot); diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c index b65a29440a0c..d541ce45daeb 100644 --- a/arch/arm64/mm/kasan_init.c +++ b/arch/arm64/mm/kasan_init.c @@ -190,7 +190,7 @@ static void __init kasan_pgd_populate(unsigned long addr, unsigned long end, */ static bool __init root_level_aligned(u64 addr) { - int shift = (ARM64_HW_PGTABLE_LEVELS(vabits_actual) - 1) * (PAGE_SHIFT - 3); + int shift = (ARM64_HW_PGTABLE_LEVELS(vabits_actual) - 1) * PTDESC_TABLE_SHIFT; return (addr % (PAGE_SIZE << shift)) == 0; } @@ -245,7 +245,7 @@ static int __init root_level_idx(u64 addr) */ u64 vabits = IS_ENABLED(CONFIG_ARM64_64K_PAGES) ? VA_BITS : vabits_actual; - int shift = (ARM64_HW_PGTABLE_LEVELS(vabits) - 1) * (PAGE_SHIFT - 3); + int shift = (ARM64_HW_PGTABLE_LEVELS(vabits) - 1) * PTDESC_TABLE_SHIFT; return (addr & ~_PAGE_OFFSET(vabits)) >> (shift + PAGE_SHIFT); } @@ -269,7 +269,7 @@ static void __init clone_next_level(u64 addr, pgd_t *tmp_pg_dir, pud_t *pud) */ static int __init next_level_idx(u64 addr) { - int shift = (ARM64_HW_PGTABLE_LEVELS(vabits_actual) - 2) * (PAGE_SHIFT - 3); + int shift = (ARM64_HW_PGTABLE_LEVELS(vabits_actual) - 2) * PTDESC_TABLE_SHIFT; return (addr >> (shift + PAGE_SHIFT)) % PTRS_PER_PTE; } diff --git a/arch/arm64/mm/mem_encrypt.c b/arch/arm64/mm/mem_encrypt.c new file mode 100644 index 000000000000..ee3c0ab04384 --- /dev/null +++ b/arch/arm64/mm/mem_encrypt.c @@ -0,0 +1,50 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Implementation of the memory encryption/decryption API. + * + * Since the low-level details of the operation depend on the + * Confidential Computing environment (e.g. pKVM, CCA, ...), this just + * acts as a top-level dispatcher to whatever hooks may have been + * registered. + * + * Author: Will Deacon <will@kernel.org> + * Copyright (C) 2024 Google LLC + * + * "Hello, boils and ghouls!" + */ + +#include <linux/bug.h> +#include <linux/compiler.h> +#include <linux/err.h> +#include <linux/mm.h> + +#include <asm/mem_encrypt.h> + +static const struct arm64_mem_crypt_ops *crypt_ops; + +int arm64_mem_crypt_ops_register(const struct arm64_mem_crypt_ops *ops) +{ + if (WARN_ON(crypt_ops)) + return -EBUSY; + + crypt_ops = ops; + return 0; +} + +int set_memory_encrypted(unsigned long addr, int numpages) +{ + if (likely(!crypt_ops) || WARN_ON(!PAGE_ALIGNED(addr))) + return 0; + + return crypt_ops->encrypt(addr, numpages); +} +EXPORT_SYMBOL_GPL(set_memory_encrypted); + +int set_memory_decrypted(unsigned long addr, int numpages) +{ + if (likely(!crypt_ops) || WARN_ON(!PAGE_ALIGNED(addr))) + return 0; + + return crypt_ops->decrypt(addr, numpages); +} +EXPORT_SYMBOL_GPL(set_memory_decrypted); diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c index 642bdf908b22..c86c348857c4 100644 --- a/arch/arm64/mm/mmap.c +++ b/arch/arm64/mm/mmap.c @@ -83,8 +83,15 @@ arch_initcall(adjust_protection_map); pgprot_t vm_get_page_prot(unsigned long vm_flags) { - pteval_t prot = pgprot_val(protection_map[vm_flags & + ptdesc_t prot; + + /* Short circuit GCS to avoid bloating the table. */ + if (system_supports_gcs() && (vm_flags & VM_SHADOW_STACK)) { + prot = _PAGE_GCS_RO; + } else { + prot = pgprot_val(protection_map[vm_flags & (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]); + } if (vm_flags & VM_ARM64_BTI) prot |= PTE_GP; @@ -102,6 +109,17 @@ pgprot_t vm_get_page_prot(unsigned long vm_flags) if (vm_flags & VM_MTE) prot |= PTE_ATTRINDX(MT_NORMAL_TAGGED); +#ifdef CONFIG_ARCH_HAS_PKEYS + if (system_supports_poe()) { + if (vm_flags & VM_PKEY_BIT0) + prot |= PTE_PO_IDX_0; + if (vm_flags & VM_PKEY_BIT1) + prot |= PTE_PO_IDX_1; + if (vm_flags & VM_PKEY_BIT2) + prot |= PTE_PO_IDX_2; + } +#endif + return __pgprot(prot); } EXPORT_SYMBOL(vm_get_page_prot); diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 495b732d5af3..00ab1d648db6 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -25,6 +25,7 @@ #include <linux/vmalloc.h> #include <linux/set_memory.h> #include <linux/kfence.h> +#include <linux/pkeys.h> #include <asm/barrier.h> #include <asm/cputype.h> @@ -45,6 +46,13 @@ #define NO_CONT_MAPPINGS BIT(1) #define NO_EXEC_MAPPINGS BIT(2) /* assumes FEAT_HPDS is not used */ +enum pgtable_type { + TABLE_PTE, + TABLE_PMD, + TABLE_PUD, + TABLE_P4D, +}; + u64 kimage_voffset __ro_after_init; EXPORT_SYMBOL(kimage_voffset); @@ -106,41 +114,26 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, } EXPORT_SYMBOL(phys_mem_access_prot); -static phys_addr_t __init early_pgtable_alloc(int shift) +static phys_addr_t __init early_pgtable_alloc(enum pgtable_type pgtable_type) { phys_addr_t phys; - void *ptr; phys = memblock_phys_alloc_range(PAGE_SIZE, PAGE_SIZE, 0, MEMBLOCK_ALLOC_NOLEAKTRACE); if (!phys) panic("Failed to allocate page table page\n"); - /* - * The FIX_{PGD,PUD,PMD} slots may be in active use, but the FIX_PTE - * slot will be free, so we can (ab)use the FIX_PTE slot to initialise - * any level of table. - */ - ptr = pte_set_fixmap(phys); - - memset(ptr, 0, PAGE_SIZE); - - /* - * Implicit barriers also ensure the zeroed page is visible to the page - * table walker - */ - pte_clear_fixmap(); - return phys; } -bool pgattr_change_is_safe(u64 old, u64 new) +bool pgattr_change_is_safe(pteval_t old, pteval_t new) { /* * The following mapping attributes may be updated in live * kernel mappings without the need for break-before-make. */ - pteval_t mask = PTE_PXN | PTE_RDONLY | PTE_WRITE | PTE_NG; + pteval_t mask = PTE_PXN | PTE_RDONLY | PTE_WRITE | PTE_NG | + PTE_SWBITS_MASK; /* creating or taking down mappings is always safe */ if (!pte_valid(__pte(old)) || !pte_valid(__pte(new))) @@ -172,16 +165,25 @@ bool pgattr_change_is_safe(u64 old, u64 new) return ((old ^ new) & ~mask) == 0; } -static void init_pte(pmd_t *pmdp, unsigned long addr, unsigned long end, - phys_addr_t phys, pgprot_t prot) +static void init_clear_pgtable(void *table) { - pte_t *ptep; + clear_page(table); - ptep = pte_set_fixmap_offset(pmdp, addr); + /* Ensure the zeroing is observed by page table walks. */ + dsb(ishst); +} + +static void init_pte(pte_t *ptep, unsigned long addr, unsigned long end, + phys_addr_t phys, pgprot_t prot) +{ do { pte_t old_pte = __ptep_get(ptep); - __set_pte(ptep, pfn_pte(__phys_to_pfn(phys), prot)); + /* + * Required barriers to make this visible to the table walker + * are deferred to the end of alloc_init_cont_pte(). + */ + __set_pte_nosync(ptep, pfn_pte(__phys_to_pfn(phys), prot)); /* * After the PTE entry has been populated once, we @@ -192,32 +194,35 @@ static void init_pte(pmd_t *pmdp, unsigned long addr, unsigned long end, phys += PAGE_SIZE; } while (ptep++, addr += PAGE_SIZE, addr != end); - - pte_clear_fixmap(); } static void alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { unsigned long next; pmd_t pmd = READ_ONCE(*pmdp); + pte_t *ptep; BUG_ON(pmd_sect(pmd)); if (pmd_none(pmd)) { - pmdval_t pmdval = PMD_TYPE_TABLE | PMD_TABLE_UXN; + pmdval_t pmdval = PMD_TYPE_TABLE | PMD_TABLE_UXN | PMD_TABLE_AF; phys_addr_t pte_phys; if (flags & NO_EXEC_MAPPINGS) pmdval |= PMD_TABLE_PXN; BUG_ON(!pgtable_alloc); - pte_phys = pgtable_alloc(PAGE_SHIFT); + pte_phys = pgtable_alloc(TABLE_PTE); + ptep = pte_set_fixmap(pte_phys); + init_clear_pgtable(ptep); + ptep += pte_index(addr); __pmd_populate(pmdp, pte_phys, pmdval); - pmd = READ_ONCE(*pmdp); + } else { + BUG_ON(pmd_bad(pmd)); + ptep = pte_set_fixmap_offset(pmdp, addr); } - BUG_ON(pmd_bad(pmd)); do { pgprot_t __prot = prot; @@ -229,20 +234,26 @@ static void alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, (flags & NO_CONT_MAPPINGS) == 0) __prot = __pgprot(pgprot_val(prot) | PTE_CONT); - init_pte(pmdp, addr, next, phys, __prot); + init_pte(ptep, addr, next, phys, __prot); + ptep += pte_index(next) - pte_index(addr); phys += next - addr; } while (addr = next, addr != end); + + /* + * Note: barriers and maintenance necessary to clear the fixmap slot + * ensure that all previous pgtable writes are visible to the table + * walker. + */ + pte_clear_fixmap(); } -static void init_pmd(pud_t *pudp, unsigned long addr, unsigned long end, +static void init_pmd(pmd_t *pmdp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), int flags) + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { unsigned long next; - pmd_t *pmdp; - pmdp = pmd_set_fixmap_offset(pudp, addr); do { pmd_t old_pmd = READ_ONCE(*pmdp); @@ -268,34 +279,38 @@ static void init_pmd(pud_t *pudp, unsigned long addr, unsigned long end, } phys += next - addr; } while (pmdp++, addr = next, addr != end); - - pmd_clear_fixmap(); } static void alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), int flags) + phys_addr_t (*pgtable_alloc)(enum pgtable_type), + int flags) { unsigned long next; pud_t pud = READ_ONCE(*pudp); + pmd_t *pmdp; /* * Check for initial section mappings in the pgd/pud. */ BUG_ON(pud_sect(pud)); if (pud_none(pud)) { - pudval_t pudval = PUD_TYPE_TABLE | PUD_TABLE_UXN; + pudval_t pudval = PUD_TYPE_TABLE | PUD_TABLE_UXN | PUD_TABLE_AF; phys_addr_t pmd_phys; if (flags & NO_EXEC_MAPPINGS) pudval |= PUD_TABLE_PXN; BUG_ON(!pgtable_alloc); - pmd_phys = pgtable_alloc(PMD_SHIFT); + pmd_phys = pgtable_alloc(TABLE_PMD); + pmdp = pmd_set_fixmap(pmd_phys); + init_clear_pgtable(pmdp); + pmdp += pmd_index(addr); __pud_populate(pudp, pmd_phys, pudval); - pud = READ_ONCE(*pudp); + } else { + BUG_ON(pud_bad(pud)); + pmdp = pmd_set_fixmap_offset(pudp, addr); } - BUG_ON(pud_bad(pud)); do { pgprot_t __prot = prot; @@ -307,15 +322,18 @@ static void alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, (flags & NO_CONT_MAPPINGS) == 0) __prot = __pgprot(pgprot_val(prot) | PTE_CONT); - init_pmd(pudp, addr, next, phys, __prot, pgtable_alloc, flags); + init_pmd(pmdp, addr, next, phys, __prot, pgtable_alloc, flags); + pmdp += pmd_index(next) - pmd_index(addr); phys += next - addr; } while (addr = next, addr != end); + + pmd_clear_fixmap(); } static void alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { unsigned long next; @@ -323,19 +341,22 @@ static void alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end, pud_t *pudp; if (p4d_none(p4d)) { - p4dval_t p4dval = P4D_TYPE_TABLE | P4D_TABLE_UXN; + p4dval_t p4dval = P4D_TYPE_TABLE | P4D_TABLE_UXN | P4D_TABLE_AF; phys_addr_t pud_phys; if (flags & NO_EXEC_MAPPINGS) p4dval |= P4D_TABLE_PXN; BUG_ON(!pgtable_alloc); - pud_phys = pgtable_alloc(PUD_SHIFT); + pud_phys = pgtable_alloc(TABLE_PUD); + pudp = pud_set_fixmap(pud_phys); + init_clear_pgtable(pudp); + pudp += pud_index(addr); __p4d_populate(p4dp, pud_phys, p4dval); - p4d = READ_ONCE(*p4dp); + } else { + BUG_ON(p4d_bad(p4d)); + pudp = pud_set_fixmap_offset(p4dp, addr); } - BUG_ON(p4d_bad(p4d)); - pudp = pud_set_fixmap_offset(p4dp, addr); do { pud_t old_pud = READ_ONCE(*pudp); @@ -370,7 +391,7 @@ static void alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end, static void alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { unsigned long next; @@ -378,19 +399,22 @@ static void alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end, p4d_t *p4dp; if (pgd_none(pgd)) { - pgdval_t pgdval = PGD_TYPE_TABLE | PGD_TABLE_UXN; + pgdval_t pgdval = PGD_TYPE_TABLE | PGD_TABLE_UXN | PGD_TABLE_AF; phys_addr_t p4d_phys; if (flags & NO_EXEC_MAPPINGS) pgdval |= PGD_TABLE_PXN; BUG_ON(!pgtable_alloc); - p4d_phys = pgtable_alloc(P4D_SHIFT); + p4d_phys = pgtable_alloc(TABLE_P4D); + p4dp = p4d_set_fixmap(p4d_phys); + init_clear_pgtable(p4dp); + p4dp += p4d_index(addr); __pgd_populate(pgdp, p4d_phys, pgdval); - pgd = READ_ONCE(*pgdp); + } else { + BUG_ON(pgd_bad(pgd)); + p4dp = p4d_set_fixmap_offset(pgdp, addr); } - BUG_ON(pgd_bad(pgd)); - p4dp = p4d_set_fixmap_offset(pgdp, addr); do { p4d_t old_p4d = READ_ONCE(*p4dp); @@ -411,7 +435,7 @@ static void alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end, static void __create_pgd_mapping_locked(pgd_t *pgdir, phys_addr_t phys, unsigned long virt, phys_addr_t size, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { unsigned long addr, end, next; @@ -439,7 +463,7 @@ static void __create_pgd_mapping_locked(pgd_t *pgdir, phys_addr_t phys, static void __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, unsigned long virt, phys_addr_t size, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { mutex_lock(&fixmap_lock); @@ -452,38 +476,48 @@ static void __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, extern __alias(__create_pgd_mapping_locked) void create_kpti_ng_temp_pgd(pgd_t *pgdir, phys_addr_t phys, unsigned long virt, phys_addr_t size, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), int flags); + phys_addr_t (*pgtable_alloc)(enum pgtable_type), + int flags); #endif -static phys_addr_t __pgd_pgtable_alloc(int shift) -{ - void *ptr = (void *)__get_free_page(GFP_PGTABLE_KERNEL); - BUG_ON(!ptr); +static phys_addr_t __pgd_pgtable_alloc(struct mm_struct *mm, + enum pgtable_type pgtable_type) +{ + /* Page is zeroed by init_clear_pgtable() so don't duplicate effort. */ + struct ptdesc *ptdesc = pagetable_alloc(GFP_PGTABLE_KERNEL & ~__GFP_ZERO, 0); + phys_addr_t pa; + + BUG_ON(!ptdesc); + pa = page_to_phys(ptdesc_page(ptdesc)); + + switch (pgtable_type) { + case TABLE_PTE: + BUG_ON(!pagetable_pte_ctor(mm, ptdesc)); + break; + case TABLE_PMD: + BUG_ON(!pagetable_pmd_ctor(mm, ptdesc)); + break; + case TABLE_PUD: + pagetable_pud_ctor(ptdesc); + break; + case TABLE_P4D: + pagetable_p4d_ctor(ptdesc); + break; + } - /* Ensure the zeroed page is visible to the page table walker */ - dsb(ishst); - return __pa(ptr); + return pa; } -static phys_addr_t pgd_pgtable_alloc(int shift) +static phys_addr_t __maybe_unused +pgd_pgtable_alloc_init_mm(enum pgtable_type pgtable_type) { - phys_addr_t pa = __pgd_pgtable_alloc(shift); - struct ptdesc *ptdesc = page_ptdesc(phys_to_page(pa)); - - /* - * Call proper page table ctor in case later we need to - * call core mm functions like apply_to_page_range() on - * this pre-allocated page table. - * - * We don't select ARCH_ENABLE_SPLIT_PMD_PTLOCK if pmd is - * folded, and if so pagetable_pte_ctor() becomes nop. - */ - if (shift == PAGE_SHIFT) - BUG_ON(!pagetable_pte_ctor(ptdesc)); - else if (shift == PMD_SHIFT) - BUG_ON(!pagetable_pmd_ctor(ptdesc)); + return __pgd_pgtable_alloc(&init_mm, pgtable_type); +} - return pa; +static phys_addr_t +pgd_pgtable_alloc_special_mm(enum pgtable_type pgtable_type) +{ + return __pgd_pgtable_alloc(NULL, pgtable_type); } /* @@ -515,7 +549,7 @@ void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys, flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; __create_pgd_mapping(mm->pgd, phys, virt, size, prot, - pgd_pgtable_alloc, flags); + pgd_pgtable_alloc_special_mm, flags); } static void update_mapping_prot(phys_addr_t phys, unsigned long virt, @@ -729,7 +763,7 @@ static int __init map_entry_trampoline(void) memset(tramp_pg_dir, 0, PGD_SIZE); __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, entry_tramp_text_size(), prot, - __pgd_pgtable_alloc, NO_BLOCK_MAPPINGS); + pgd_pgtable_alloc_init_mm, NO_BLOCK_MAPPINGS); /* Map both the text and data into the kernel page table */ for (i = 0; i < DIV_ROUND_UP(entry_tramp_text_size(), PAGE_SIZE); i++) @@ -1154,15 +1188,19 @@ int __meminit vmemmap_check_pmd(pmd_t *pmdp, int node, unsigned long addr, unsigned long next) { vmemmap_verify((pte_t *)pmdp, node, addr, next); - return 1; + + return pmd_sect(READ_ONCE(*pmdp)); } int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, struct vmem_altmap *altmap) { WARN_ON((start < VMEMMAP_START) || (end > VMEMMAP_END)); + /* [start, end] should be within one section */ + WARN_ON_ONCE(end - start > PAGES_PER_SECTION * sizeof(struct page)); - if (!IS_ENABLED(CONFIG_ARM64_4K_PAGES)) + if (!IS_ENABLED(CONFIG_ARM64_4K_PAGES) || + (end - start < PAGES_PER_SECTION * sizeof(struct page))) return vmemmap_populate_basepages(start, end, node, altmap); else return vmemmap_populate_hugepages(start, end, node, altmap); @@ -1267,7 +1305,8 @@ int pud_free_pmd_page(pud_t *pudp, unsigned long addr) next = addr; end = addr + PUD_SIZE; do { - pmd_free_pte_page(pmdp, next); + if (pmd_present(pmdp_get(pmdp))) + pmd_free_pte_page(pmdp, next); } while (pmdp++, next += PMD_SIZE, next != end); pud_clear(pudp); @@ -1331,7 +1370,7 @@ int arch_add_memory(int nid, u64 start, u64 size, flags |= NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; __create_pgd_mapping(swapper_pg_dir, start, __phys_to_virt(start), - size, params->pgprot, __pgd_pgtable_alloc, + size, params->pgprot, pgd_pgtable_alloc_init_mm, flags); memblock_clear_nomap(start, size); @@ -1342,7 +1381,8 @@ int arch_add_memory(int nid, u64 start, u64 size, __remove_pgd_mapping(swapper_pg_dir, __phys_to_virt(start), size); else { - max_pfn = PFN_UP(start + size); + /* Address of hotplugged memory can be smaller */ + max_pfn = max(max_pfn, PFN_UP(start + size)); max_low_pfn = max_pfn; } @@ -1535,3 +1575,45 @@ void __cpu_replace_ttbr1(pgd_t *pgdp, bool cnp) cpu_uninstall_idmap(); } + +#ifdef CONFIG_ARCH_HAS_PKEYS +int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, unsigned long init_val) +{ + u64 new_por; + u64 old_por; + + if (!system_supports_poe()) + return -ENOSPC; + + /* + * This code should only be called with valid 'pkey' + * values originating from in-kernel users. Complain + * if a bad value is observed. + */ + if (WARN_ON_ONCE(pkey >= arch_max_pkey())) + return -EINVAL; + + /* Set the bits we need in POR: */ + new_por = POE_RWX; + if (init_val & PKEY_DISABLE_WRITE) + new_por &= ~POE_W; + if (init_val & PKEY_DISABLE_ACCESS) + new_por &= ~POE_RW; + if (init_val & PKEY_DISABLE_READ) + new_por &= ~POE_R; + if (init_val & PKEY_DISABLE_EXECUTE) + new_por &= ~POE_X; + + /* Shift the bits in to the correct place in POR for pkey: */ + new_por = POR_ELx_PERM_PREP(pkey, new_por); + + /* Get old POR and mask off any old bits in place: */ + old_por = read_sysreg_s(SYS_POR_EL0); + old_por &= ~(POE_MASK << POR_ELx_PERM_SHIFT(pkey)); + + /* Write old part along with new part: */ + write_sysreg_s(old_por | new_por, SYS_POR_EL0); + + return 0; +} +#endif diff --git a/arch/arm64/mm/mteswap.c b/arch/arm64/mm/mteswap.c index a31833e3ddc5..63e8d72f202a 100644 --- a/arch/arm64/mm/mteswap.c +++ b/arch/arm64/mm/mteswap.c @@ -68,6 +68,13 @@ void mte_invalidate_tags(int type, pgoff_t offset) mte_free_tag_storage(tags); } +static inline void __mte_invalidate_tags(struct page *page) +{ + swp_entry_t entry = page_swap_entry(page); + + mte_invalidate_tags(swp_type(entry), swp_offset(entry)); +} + void mte_invalidate_tags_area(int type) { swp_entry_t entry = swp_entry(type, 0); @@ -83,3 +90,41 @@ void mte_invalidate_tags_area(int type) } xa_unlock(&mte_pages); } + +int arch_prepare_to_swap(struct folio *folio) +{ + long i, nr; + int err; + + if (!system_supports_mte()) + return 0; + + nr = folio_nr_pages(folio); + + for (i = 0; i < nr; i++) { + err = mte_save_tags(folio_page(folio, i)); + if (err) + goto out; + } + return 0; + +out: + while (i--) + __mte_invalidate_tags(folio_page(folio, i)); + return err; +} + +void arch_swap_restore(swp_entry_t entry, struct folio *folio) +{ + long i, nr; + + if (!system_supports_mte()) + return; + + nr = folio_nr_pages(folio); + + for (i = 0; i < nr; i++) { + mte_restore_tags(entry, folio_page(folio, i)); + entry.val++; + } +} diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 0c4e3ecf989d..04d4a8f676db 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -5,10 +5,12 @@ #include <linux/kernel.h> #include <linux/mm.h> #include <linux/module.h> +#include <linux/mem_encrypt.h> #include <linux/sched.h> #include <linux/vmalloc.h> #include <asm/cacheflush.h> +#include <asm/pgtable-prot.h> #include <asm/set_memory.h> #include <asm/tlbflush.h> #include <asm/kfence.h> @@ -23,14 +25,16 @@ bool rodata_full __ro_after_init = IS_ENABLED(CONFIG_RODATA_FULL_DEFAULT_ENABLED bool can_set_direct_map(void) { /* - * rodata_full and DEBUG_PAGEALLOC require linear map to be - * mapped at page granularity, so that it is possible to + * rodata_full, DEBUG_PAGEALLOC and a Realm guest all require linear + * map to be mapped at page granularity, so that it is possible to * protect/unprotect single pages. * * KFENCE pool requires page-granular mapping if initialized late. + * + * Realms need to make pages shared/protected at page granularity. */ return rodata_full || debug_pagealloc_enabled() || - arm64_kfence_can_set_direct_map(); + arm64_kfence_can_set_direct_map() || is_realm_world(); } static int change_page_range(pte_t *ptep, unsigned long addr, void *data) @@ -60,7 +64,13 @@ static int __change_memory_common(unsigned long start, unsigned long size, ret = apply_to_page_range(&init_mm, start, size, change_page_range, &data); - flush_tlb_kernel_range(start, start + size); + /* + * If the memory is being made valid without changing any other bits + * then a TLBI isn't required as a non-valid entry cannot be cached in + * the TLB. + */ + if (pgprot_val(set_mask) != PTE_VALID || pgprot_val(clear_mask)) + flush_tlb_kernel_range(start, start + size); return ret; } @@ -86,8 +96,8 @@ static int change_memory_common(unsigned long addr, int numpages, * we are operating on does not result in such splitting. * * Let's restrict ourselves to mappings created by vmalloc (or vmap). - * Those are guaranteed to consist entirely of page mappings, and - * splitting is never needed. + * Disallow VM_ALLOW_HUGE_VMAP mappings to guarantee that only page + * mappings are updated and splitting is never needed. * * So check whether the [addr, addr + size) interval is entirely * covered by precisely one VM area that has the VM_ALLOC flag set. @@ -95,7 +105,7 @@ static int change_memory_common(unsigned long addr, int numpages, area = find_vm_area((void *)addr); if (!area || end > (unsigned long)kasan_reset_tag(area->addr) + area->size || - !(area->flags & VM_ALLOC)) + ((area->flags & (VM_ALLOC | VM_ALLOW_HUGE_VMAP)) != VM_ALLOC)) return -EINVAL; if (!numpages) @@ -192,7 +202,103 @@ int set_direct_map_default_noflush(struct page *page) PAGE_SIZE, change_page_range, &data); } +static int __set_memory_enc_dec(unsigned long addr, + int numpages, + bool encrypt) +{ + unsigned long set_prot = 0, clear_prot = 0; + phys_addr_t start, end; + int ret; + + if (!is_realm_world()) + return 0; + + if (!__is_lm_address(addr)) + return -EINVAL; + + start = __virt_to_phys(addr); + end = start + numpages * PAGE_SIZE; + + if (encrypt) + clear_prot = PROT_NS_SHARED; + else + set_prot = PROT_NS_SHARED; + + /* + * Break the mapping before we make any changes to avoid stale TLB + * entries or Synchronous External Aborts caused by RIPAS_EMPTY + */ + ret = __change_memory_common(addr, PAGE_SIZE * numpages, + __pgprot(set_prot), + __pgprot(clear_prot | PTE_VALID)); + + if (ret) + return ret; + + if (encrypt) + ret = rsi_set_memory_range_protected(start, end); + else + ret = rsi_set_memory_range_shared(start, end); + + if (ret) + return ret; + + return __change_memory_common(addr, PAGE_SIZE * numpages, + __pgprot(PTE_VALID), + __pgprot(0)); +} + +static int realm_set_memory_encrypted(unsigned long addr, int numpages) +{ + int ret = __set_memory_enc_dec(addr, numpages, true); + + /* + * If the request to change state fails, then the only sensible cause + * of action for the caller is to leak the memory + */ + WARN(ret, "Failed to encrypt memory, %d pages will be leaked", + numpages); + + return ret; +} + +static int realm_set_memory_decrypted(unsigned long addr, int numpages) +{ + int ret = __set_memory_enc_dec(addr, numpages, false); + + WARN(ret, "Failed to decrypt memory, %d pages will be leaked", + numpages); + + return ret; +} + +static const struct arm64_mem_crypt_ops realm_crypt_ops = { + .encrypt = realm_set_memory_encrypted, + .decrypt = realm_set_memory_decrypted, +}; + +int realm_register_memory_enc_ops(void) +{ + return arm64_mem_crypt_ops_register(&realm_crypt_ops); +} + +int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid) +{ + unsigned long addr = (unsigned long)page_address(page); + + if (!can_set_direct_map()) + return 0; + + return set_memory_valid(addr, nr, valid); +} + #ifdef CONFIG_DEBUG_PAGEALLOC +/* + * This is - apart from the return value - doing the same + * thing as the new set_direct_map_valid_noflush() function. + * + * Unify? Explain the conceptual differences? + */ void __kernel_map_pages(struct page *page, int numpages, int enable) { if (!can_set_direct_map()) @@ -219,9 +325,6 @@ bool kernel_page_present(struct page *page) pte_t *ptep; unsigned long addr = (unsigned long)page_address(page); - if (!can_set_direct_map()) - return true; - pgdp = pgd_offset_k(addr); if (pgd_none(READ_ONCE(*pgdp))) return false; diff --git a/arch/arm64/mm/pgd.c b/arch/arm64/mm/pgd.c index 0c501cabc238..8160cff35089 100644 --- a/arch/arm64/mm/pgd.c +++ b/arch/arm64/mm/pgd.c @@ -33,7 +33,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm) gfp_t gfp = GFP_PGTABLE_USER; if (pgdir_is_page_size()) - return (pgd_t *)__get_free_page(gfp); + return __pgd_alloc(mm, 0); else return kmem_cache_alloc(pgd_cache, gfp); } @@ -41,7 +41,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm) void pgd_free(struct mm_struct *mm, pgd_t *pgd) { if (pgdir_is_page_size()) - free_page((unsigned long)pgd); + __pgd_free(mm, pgd); else kmem_cache_free(pgd_cache, pgd); } diff --git a/arch/arm64/mm/physaddr.c b/arch/arm64/mm/physaddr.c index cde44c13dda1..7d94e09b01b3 100644 --- a/arch/arm64/mm/physaddr.c +++ b/arch/arm64/mm/physaddr.c @@ -10,7 +10,7 @@ phys_addr_t __virt_to_phys(unsigned long x) { WARN(!__is_lm_address(__tag_reset(x)), - "virt_to_phys used for non-linear address: %pK (%pS)\n", + "virt_to_phys used for non-linear address: %p (%pS)\n", (void *)x, (void *)x); diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 9d40f3ffd8d2..80d470aa469d 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -36,8 +36,6 @@ #define TCR_KASLR_FLAGS 0 #endif -#define TCR_SMP_FLAGS TCR_SHARED - /* PTWs cacheable, inner/outer WBWA */ #define TCR_CACHE_FLAGS TCR_IRGN_WBWA | TCR_ORGN_WBWA @@ -135,14 +133,6 @@ SYM_FUNC_START(cpu_do_resume) msr tcr_el1, x8 msr vbar_el1, x9 - - /* - * __cpu_setup() cleared MDSCR_EL1.MDE and friends, before unmasking - * debug exceptions. By restoring MDSCR_EL1 here, we may take a debug - * exception. Mask them until local_daif_restore() in cpu_suspend() - * resets them. - */ - disable_daif msr mdscr_el1, x10 msr sctlr_el1, x12 @@ -466,8 +456,6 @@ SYM_FUNC_START(__cpu_setup) msr cpacr_el1, xzr // Reset cpacr_el1 mov x1, #1 << 12 // Reset mdscr_el1 and disable msr mdscr_el1, x1 // access to the DCC from EL0 - isb // Unmask debug exceptions now, - enable_dbg // since this is per-cpu reset_pmuserenr_el0 x1 // Disable PMU access from EL0 reset_amuserenr_el0 x1 // Disable AMU access from EL0 @@ -477,10 +465,12 @@ SYM_FUNC_START(__cpu_setup) */ mair .req x17 tcr .req x16 + tcr2 .req x15 mov_q mair, MAIR_EL1_SET mov_q tcr, TCR_T0SZ(IDMAP_VA_BITS) | TCR_T1SZ(VA_BITS_MIN) | TCR_CACHE_FLAGS | \ - TCR_SMP_FLAGS | TCR_TG_FLAGS | TCR_KASLR_FLAGS | TCR_ASID16 | \ + TCR_SHARED | TCR_TG_FLAGS | TCR_KASLR_FLAGS | TCR_ASID16 | \ TCR_TBI0 | TCR_A1 | TCR_KASAN_SW_FLAGS | TCR_MTE_FLAGS + mov tcr2, xzr tcr_clear_errata_bits tcr, x9, x5 @@ -505,9 +495,14 @@ alternative_else_nop_endif * via capabilities. */ mrs x9, ID_AA64MMFR1_EL1 - and x9, x9, ID_AA64MMFR1_EL1_HAFDBS_MASK + ubfx x9, x9, ID_AA64MMFR1_EL1_HAFDBS_SHIFT, #4 cbz x9, 1f orr tcr, tcr, #TCR_HA // hardware Access flag update +#ifdef CONFIG_ARM64_HAFT + cmp x9, ID_AA64MMFR1_EL1_HAFDBS_HAFT + b.lt 1f + orr tcr2, tcr2, TCR2_EL1_HAFT +#endif /* CONFIG_ARM64_HAFT */ 1: #endif /* CONFIG_ARM64_HW_AFDBM */ msr mair_el1, mair @@ -517,31 +512,22 @@ alternative_else_nop_endif ubfx x1, x1, #ID_AA64MMFR3_EL1_S1PIE_SHIFT, #4 cbz x1, .Lskip_indirection - /* - * The PROT_* macros describing the various memory types may resolve to - * C expressions if they include the PTE_MAYBE_* macros, and so they - * can only be used from C code. The PIE_E* constants below are also - * defined in terms of those macros, but will mask out those - * PTE_MAYBE_* constants, whether they are set or not. So #define them - * as 0x0 here so we can evaluate the PIE_E* constants in asm context. - */ - -#define PTE_MAYBE_NG 0 -#define PTE_MAYBE_SHARED 0 - - mov_q x0, PIE_E0 + mov_q x0, PIE_E0_ASM msr REG_PIRE0_EL1, x0 - mov_q x0, PIE_E1 + mov_q x0, PIE_E1_ASM msr REG_PIR_EL1, x0 -#undef PTE_MAYBE_NG -#undef PTE_MAYBE_SHARED - - mov x0, TCR2_EL1x_PIE + orr tcr2, tcr2, TCR2_EL1_PIE msr REG_TCR2_EL1, x0 .Lskip_indirection: + mrs_s x1, SYS_ID_AA64MMFR3_EL1 + ubfx x1, x1, #ID_AA64MMFR3_EL1_TCRX_SHIFT, #4 + cbz x1, 1f + msr REG_TCR2_EL1, tcr2 +1: + /* * Prepare SCTLR */ @@ -550,4 +536,5 @@ alternative_else_nop_endif .unreq mair .unreq tcr + .unreq tcr2 SYM_FUNC_END(__cpu_setup) diff --git a/arch/arm64/mm/ptdump.c b/arch/arm64/mm/ptdump.c index 6986827e0d64..421a5de806c6 100644 --- a/arch/arm64/mm/ptdump.c +++ b/arch/arm64/mm/ptdump.c @@ -38,33 +38,7 @@ seq_printf(m, fmt); \ }) -/* - * The page dumper groups page table entries of the same type into a single - * description. It uses pg_state to track the range information while - * iterating over the pte entries. When the continuity is broken it then - * dumps out a description of the range. - */ -struct pg_state { - struct ptdump_state ptdump; - struct seq_file *seq; - const struct addr_marker *marker; - const struct mm_struct *mm; - unsigned long start_address; - int level; - u64 current_prot; - bool check_wx; - unsigned long wx_pages; - unsigned long uxn_pages; -}; - -struct prot_bits { - u64 mask; - u64 val; - const char *set; - const char *clear; -}; - -static const struct prot_bits pte_bits[] = { +static const struct ptdump_prot_bits pte_bits[] = { { .mask = PTE_VALID, .val = PTE_VALID, @@ -106,10 +80,10 @@ static const struct prot_bits pte_bits[] = { .set = "CON", .clear = " ", }, { - .mask = PTE_TABLE_BIT, - .val = PTE_TABLE_BIT, - .set = " ", - .clear = "BLK", + .mask = PMD_TYPE_MASK, + .val = PMD_TYPE_SECT, + .set = "BLK", + .clear = " ", }, { .mask = PTE_UXN, .val = PTE_UXN, @@ -143,14 +117,7 @@ static const struct prot_bits pte_bits[] = { } }; -struct pg_level { - const struct prot_bits *bits; - char name[4]; - int num; - u64 mask; -}; - -static struct pg_level pg_level[] __ro_after_init = { +static struct ptdump_pg_level kernel_pg_levels[] __ro_after_init = { { /* pgd */ .name = "PGD", .bits = pte_bits, @@ -174,7 +141,7 @@ static struct pg_level pg_level[] __ro_after_init = { }, }; -static void dump_prot(struct pg_state *st, const struct prot_bits *bits, +static void dump_prot(struct ptdump_pg_state *st, const struct ptdump_prot_bits *bits, size_t num) { unsigned i; @@ -192,7 +159,7 @@ static void dump_prot(struct pg_state *st, const struct prot_bits *bits, } } -static void note_prot_uxn(struct pg_state *st, unsigned long addr) +static void note_prot_uxn(struct ptdump_pg_state *st, unsigned long addr) { if (!st->check_wx) return; @@ -206,7 +173,7 @@ static void note_prot_uxn(struct pg_state *st, unsigned long addr) st->uxn_pages += (addr - st->start_address) / PAGE_SIZE; } -static void note_prot_wx(struct pg_state *st, unsigned long addr) +static void note_prot_wx(struct ptdump_pg_state *st, unsigned long addr) { if (!st->check_wx) return; @@ -221,16 +188,17 @@ static void note_prot_wx(struct pg_state *st, unsigned long addr) st->wx_pages += (addr - st->start_address) / PAGE_SIZE; } -static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level, - u64 val) +void note_page(struct ptdump_state *pt_st, unsigned long addr, int level, + pteval_t val) { - struct pg_state *st = container_of(pt_st, struct pg_state, ptdump); + struct ptdump_pg_state *st = container_of(pt_st, struct ptdump_pg_state, ptdump); + struct ptdump_pg_level *pg_level = st->pg_level; static const char units[] = "KMGTPE"; - u64 prot = 0; + ptdesc_t prot = 0; /* check if the current level has been folded dynamically */ - if ((level == 1 && mm_p4d_folded(st->mm)) || - (level == 2 && mm_pud_folded(st->mm))) + if (st->mm && ((level == 1 && mm_p4d_folded(st->mm)) || + (level == 2 && mm_pud_folded(st->mm)))) level = 0; if (level >= 0) @@ -283,21 +251,59 @@ static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level, } +void note_page_pte(struct ptdump_state *pt_st, unsigned long addr, pte_t pte) +{ + note_page(pt_st, addr, 4, pte_val(pte)); +} + +void note_page_pmd(struct ptdump_state *pt_st, unsigned long addr, pmd_t pmd) +{ + note_page(pt_st, addr, 3, pmd_val(pmd)); +} + +void note_page_pud(struct ptdump_state *pt_st, unsigned long addr, pud_t pud) +{ + note_page(pt_st, addr, 2, pud_val(pud)); +} + +void note_page_p4d(struct ptdump_state *pt_st, unsigned long addr, p4d_t p4d) +{ + note_page(pt_st, addr, 1, p4d_val(p4d)); +} + +void note_page_pgd(struct ptdump_state *pt_st, unsigned long addr, pgd_t pgd) +{ + note_page(pt_st, addr, 0, pgd_val(pgd)); +} + +void note_page_flush(struct ptdump_state *pt_st) +{ + pte_t pte_zero = {0}; + + note_page(pt_st, 0, -1, pte_val(pte_zero)); +} + void ptdump_walk(struct seq_file *s, struct ptdump_info *info) { unsigned long end = ~0UL; - struct pg_state st; + struct ptdump_pg_state st; if (info->base_addr < TASK_SIZE_64) end = TASK_SIZE_64; - st = (struct pg_state){ + st = (struct ptdump_pg_state){ .seq = s, .marker = info->markers, .mm = info->mm, + .pg_level = &kernel_pg_levels[0], .level = -1, .ptdump = { - .note_page = note_page, + .note_page_pte = note_page_pte, + .note_page_pmd = note_page_pmd, + .note_page_pud = note_page_pud, + .note_page_p4d = note_page_p4d, + .note_page_pgd = note_page_pgd, + .note_page_flush = note_page_flush, .range = (struct ptdump_range[]){ {info->base_addr, end}, {0, 0} @@ -312,10 +318,10 @@ static void __init ptdump_initialize(void) { unsigned i, j; - for (i = 0; i < ARRAY_SIZE(pg_level); i++) - if (pg_level[i].bits) - for (j = 0; j < pg_level[i].num; j++) - pg_level[i].mask |= pg_level[i].bits[j].mask; + for (i = 0; i < ARRAY_SIZE(kernel_pg_levels); i++) + if (kernel_pg_levels[i].bits) + for (j = 0; j < kernel_pg_levels[i].num; j++) + kernel_pg_levels[i].mask |= kernel_pg_levels[i].bits[j].mask; } static struct ptdump_info kernel_ptdump_info __ro_after_init = { @@ -324,16 +330,22 @@ static struct ptdump_info kernel_ptdump_info __ro_after_init = { bool ptdump_check_wx(void) { - struct pg_state st = { + struct ptdump_pg_state st = { .seq = NULL, .marker = (struct addr_marker[]) { { 0, NULL}, { -1, NULL}, }, + .pg_level = &kernel_pg_levels[0], .level = -1, .check_wx = true, .ptdump = { - .note_page = note_page, + .note_page_pte = note_page_pte, + .note_page_pmd = note_page_pmd, + .note_page_pud = note_page_pud, + .note_page_p4d = note_page_p4d, + .note_page_pgd = note_page_pgd, + .note_page_flush = note_page_flush, .range = (struct ptdump_range[]) { {_PAGE_OFFSET(vabits_actual), ~0UL}, {0, 0} diff --git a/arch/arm64/mm/trans_pgd.c b/arch/arm64/mm/trans_pgd.c index 5139a28130c0..18543b603c77 100644 --- a/arch/arm64/mm/trans_pgd.c +++ b/arch/arm64/mm/trans_pgd.c @@ -42,20 +42,22 @@ static void _copy_pte(pte_t *dst_ptep, pte_t *src_ptep, unsigned long addr) * the temporary mappings we use during restore. */ __set_pte(dst_ptep, pte_mkwrite_novma(pte)); - } else if ((debug_pagealloc_enabled() || - is_kfence_address((void *)addr)) && !pte_none(pte)) { + } else if (!pte_none(pte)) { /* * debug_pagealloc will removed the PTE_VALID bit if * the page isn't in use by the resume kernel. It may have * been in use by the original kernel, in which case we need * to put it back in our copy to do the restore. * + * Other cases include kfence / vmalloc / memfd_secret which + * may call `set_direct_map_invalid_noflush()`. + * * Before marking this entry valid, check the pfn should * be mapped. */ BUG_ON(!pfn_valid(pte_pfn(pte))); - __set_pte(dst_ptep, pte_mkpresent(pte_mkwrite_novma(pte))); + __set_pte(dst_ptep, pte_mkvalid(pte_mkwrite_novma(pte))); } } @@ -160,6 +162,13 @@ static int copy_p4d(struct trans_pgd_info *info, pgd_t *dst_pgdp, unsigned long next; unsigned long addr = start; + if (pgd_none(READ_ONCE(*dst_pgdp))) { + dst_p4dp = trans_alloc(info); + if (!dst_p4dp) + return -ENOMEM; + pgd_populate(NULL, dst_pgdp, dst_p4dp); + } + dst_p4dp = p4d_offset(dst_pgdp, start); src_p4dp = p4d_offset(src_pgdp, start); do { |