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-rw-r--r--arch/arm64/mm/context.c54
-rw-r--r--arch/arm64/mm/dump.c21
-rw-r--r--arch/arm64/mm/extable.c2
-rw-r--r--arch/arm64/mm/fault.c86
-rw-r--r--arch/arm64/mm/flush.c4
-rw-r--r--arch/arm64/mm/hugetlbpage.c2
-rw-r--r--arch/arm64/mm/init.c162
-rw-r--r--arch/arm64/mm/kasan_init.c70
-rw-r--r--arch/arm64/mm/mmu.c532
-rw-r--r--arch/arm64/mm/pageattr.c46
-rw-r--r--arch/arm64/mm/proc.S40
11 files changed, 723 insertions, 296 deletions
diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c
index e87f53ff5..c90c3c5f4 100644
--- a/arch/arm64/mm/context.c
+++ b/arch/arm64/mm/context.c
@@ -24,6 +24,7 @@
#include <asm/cpufeature.h>
#include <asm/mmu_context.h>
+#include <asm/smp.h>
#include <asm/tlbflush.h>
static u32 asid_bits;
@@ -40,6 +41,45 @@ static cpumask_t tlb_flush_pending;
#define ASID_FIRST_VERSION (1UL << asid_bits)
#define NUM_USER_ASIDS ASID_FIRST_VERSION
+/* Get the ASIDBits supported by the current CPU */
+static u32 get_cpu_asid_bits(void)
+{
+ u32 asid;
+ int fld = cpuid_feature_extract_unsigned_field(read_cpuid(ID_AA64MMFR0_EL1),
+ ID_AA64MMFR0_ASID_SHIFT);
+
+ switch (fld) {
+ default:
+ pr_warn("CPU%d: Unknown ASID size (%d); assuming 8-bit\n",
+ smp_processor_id(), fld);
+ /* Fallthrough */
+ case 0:
+ asid = 8;
+ break;
+ case 2:
+ asid = 16;
+ }
+
+ return asid;
+}
+
+/* Check if the current cpu's ASIDBits is compatible with asid_bits */
+void verify_cpu_asid_bits(void)
+{
+ u32 asid = get_cpu_asid_bits();
+
+ if (asid < asid_bits) {
+ /*
+ * We cannot decrease the ASID size at runtime, so panic if we support
+ * fewer ASID bits than the boot CPU.
+ */
+ pr_crit("CPU%d: smaller ASID size(%u) than boot CPU (%u)\n",
+ smp_processor_id(), asid, asid_bits);
+ update_cpu_boot_status(CPU_PANIC_KERNEL);
+ cpu_park_loop();
+ }
+}
+
static void flush_context(unsigned int cpu)
{
int i;
@@ -187,19 +227,7 @@ switch_mm_fastpath:
static int asids_init(void)
{
- int fld = cpuid_feature_extract_field(read_cpuid(ID_AA64MMFR0_EL1), 4);
-
- switch (fld) {
- default:
- pr_warn("Unknown ASID size (%d); assuming 8-bit\n", fld);
- /* Fallthrough */
- case 0:
- asid_bits = 8;
- break;
- case 2:
- asid_bits = 16;
- }
-
+ asid_bits = get_cpu_asid_bits();
/* If we end up with more CPUs than ASIDs, expect things to crash */
WARN_ON(NUM_USER_ASIDS < num_possible_cpus());
atomic64_set(&asid_generation, ASID_FIRST_VERSION);
diff --git a/arch/arm64/mm/dump.c b/arch/arm64/mm/dump.c
index 0adbebbc2..f9271cb2f 100644
--- a/arch/arm64/mm/dump.c
+++ b/arch/arm64/mm/dump.c
@@ -27,15 +27,15 @@
#include <asm/pgtable.h>
#include <asm/pgtable-hwdef.h>
-#define LOWEST_ADDR (UL(0xffffffffffffffff) << VA_BITS)
-
struct addr_marker {
unsigned long start_address;
const char *name;
};
enum address_markers_idx {
- VMALLOC_START_NR = 0,
+ MODULES_START_NR = 0,
+ MODULES_END_NR,
+ VMALLOC_START_NR,
VMALLOC_END_NR,
#ifdef CONFIG_SPARSEMEM_VMEMMAP
VMEMMAP_START_NR,
@@ -45,12 +45,12 @@ enum address_markers_idx {
FIXADDR_END_NR,
PCI_START_NR,
PCI_END_NR,
- MODULES_START_NR,
- MODULES_END_NR,
KERNEL_SPACE_NR,
};
static struct addr_marker address_markers[] = {
+ { MODULES_VADDR, "Modules start" },
+ { MODULES_END, "Modules end" },
{ VMALLOC_START, "vmalloc() Area" },
{ VMALLOC_END, "vmalloc() End" },
#ifdef CONFIG_SPARSEMEM_VMEMMAP
@@ -61,9 +61,7 @@ static struct addr_marker address_markers[] = {
{ FIXADDR_TOP, "Fixmap end" },
{ PCI_IO_START, "PCI I/O start" },
{ PCI_IO_END, "PCI I/O end" },
- { MODULES_VADDR, "Modules start" },
- { MODULES_END, "Modules end" },
- { PAGE_OFFSET, "Kernel Mapping" },
+ { PAGE_OFFSET, "Linear Mapping" },
{ -1, NULL },
};
@@ -90,6 +88,11 @@ struct prot_bits {
static const struct prot_bits pte_bits[] = {
{
+ .mask = PTE_VALID,
+ .val = PTE_VALID,
+ .set = " ",
+ .clear = "F",
+ }, {
.mask = PTE_USER,
.val = PTE_USER,
.set = "USR",
@@ -316,7 +319,7 @@ static int ptdump_show(struct seq_file *m, void *v)
.marker = address_markers,
};
- walk_pgd(&st, &init_mm, LOWEST_ADDR);
+ walk_pgd(&st, &init_mm, VA_START);
note_page(&st, 0, 0, 0);
return 0;
diff --git a/arch/arm64/mm/extable.c b/arch/arm64/mm/extable.c
index 79444279b..81acd4706 100644
--- a/arch/arm64/mm/extable.c
+++ b/arch/arm64/mm/extable.c
@@ -11,7 +11,7 @@ int fixup_exception(struct pt_regs *regs)
fixup = search_exception_tables(instruction_pointer(regs));
if (fixup)
- regs->pc = fixup->fixup;
+ regs->pc = (unsigned long)&fixup->fixup + fixup->fixup;
return fixup != NULL;
}
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index abe2a9542..3ae4a28c4 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -81,6 +81,56 @@ void show_pte(struct mm_struct *mm, unsigned long addr)
printk("\n");
}
+#ifdef CONFIG_ARM64_HW_AFDBM
+/*
+ * This function sets the access flags (dirty, accessed), as well as write
+ * permission, and only to a more permissive setting.
+ *
+ * It needs to cope with hardware update of the accessed/dirty state by other
+ * agents in the system and can safely skip the __sync_icache_dcache() call as,
+ * like set_pte_at(), the PTE is never changed from no-exec to exec here.
+ *
+ * Returns whether or not the PTE actually changed.
+ */
+int ptep_set_access_flags(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep,
+ pte_t entry, int dirty)
+{
+ pteval_t old_pteval;
+ unsigned int tmp;
+
+ if (pte_same(*ptep, entry))
+ return 0;
+
+ /* only preserve the access flags and write permission */
+ pte_val(entry) &= PTE_AF | PTE_WRITE | PTE_DIRTY;
+
+ /*
+ * PTE_RDONLY is cleared by default in the asm below, so set it in
+ * back if necessary (read-only or clean PTE).
+ */
+ if (!pte_write(entry) || !dirty)
+ pte_val(entry) |= PTE_RDONLY;
+
+ /*
+ * Setting the flags must be done atomically to avoid racing with the
+ * hardware update of the access/dirty state.
+ */
+ asm volatile("// ptep_set_access_flags\n"
+ " prfm pstl1strm, %2\n"
+ "1: ldxr %0, %2\n"
+ " and %0, %0, %3 // clear PTE_RDONLY\n"
+ " orr %0, %0, %4 // set flags\n"
+ " stxr %w1, %0, %2\n"
+ " cbnz %w1, 1b\n"
+ : "=&r" (old_pteval), "=&r" (tmp), "+Q" (pte_val(*ptep))
+ : "L" (~PTE_RDONLY), "r" (pte_val(entry)));
+
+ flush_tlb_fix_spurious_fault(vma, address);
+ return 1;
+}
+#endif
+
/*
* The kernel tried to access some page that wasn't present.
*/
@@ -192,6 +242,14 @@ out:
return fault;
}
+static inline int permission_fault(unsigned int esr)
+{
+ unsigned int ec = (esr & ESR_ELx_EC_MASK) >> ESR_ELx_EC_SHIFT;
+ unsigned int fsc_type = esr & ESR_ELx_FSC_TYPE;
+
+ return (ec == ESR_ELx_EC_DABT_CUR && fsc_type == ESR_ELx_FSC_PERM);
+}
+
static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
struct pt_regs *regs)
{
@@ -225,12 +283,13 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
mm_flags |= FAULT_FLAG_WRITE;
}
- /*
- * PAN bit set implies the fault happened in kernel space, but not
- * in the arch's user access functions.
- */
- if (IS_ENABLED(CONFIG_ARM64_PAN) && (regs->pstate & PSR_PAN_BIT))
- goto no_context;
+ if (permission_fault(esr) && (addr < USER_DS)) {
+ if (get_fs() == KERNEL_DS)
+ die("Accessing user space memory with fs=KERNEL_DS", regs, esr);
+
+ if (!search_exception_tables(regs->pc))
+ die("Accessing user space memory outside uaccess.h routines", regs, esr);
+ }
/*
* As per x86, we may deadlock here. However, since the kernel only
@@ -295,7 +354,7 @@ retry:
up_read(&mm->mmap_sem);
/*
- * Handle the "normal" case first - VM_FAULT_MAJOR / VM_FAULT_MINOR
+ * Handle the "normal" case first - VM_FAULT_MAJOR
*/
if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP |
VM_FAULT_BADACCESS))))
@@ -568,3 +627,16 @@ void cpu_enable_pan(void *__unused)
config_sctlr_el1(SCTLR_EL1_SPAN, 0);
}
#endif /* CONFIG_ARM64_PAN */
+
+#ifdef CONFIG_ARM64_UAO
+/*
+ * Kernel threads have fs=KERNEL_DS by default, and don't need to call
+ * set_fs(), devtmpfs in particular relies on this behaviour.
+ * We need to enable the feature at runtime (instead of adding it to
+ * PSR_MODE_EL1h) as the feature may not be implemented by the cpu.
+ */
+void cpu_enable_uao(void *__unused)
+{
+ asm(SET_PSTATE_UAO(1));
+}
+#endif /* CONFIG_ARM64_UAO */
diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
index 60585bde1..dbd12ea8c 100644
--- a/arch/arm64/mm/flush.c
+++ b/arch/arm64/mm/flush.c
@@ -58,17 +58,13 @@ static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
* Copy user data from/to a page which is mapped into a different processes
* address space. Really, we want to allow our "user space" model to handle
* this.
- *
- * Note that this code needs to run on the current CPU.
*/
void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
unsigned long uaddr, void *dst, const void *src,
unsigned long len)
{
- preempt_disable();
memcpy(dst, src, len);
flush_ptrace_access(vma, page, uaddr, dst, len);
- preempt_enable();
}
void __sync_icache_dcache(pte_t pte, unsigned long addr)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index da30529bb..589fd28e1 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -124,7 +124,7 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
* will be no pte_unmap() to correspond with this
* pte_alloc_map().
*/
- pte = pte_alloc_map(mm, NULL, pmd, addr);
+ pte = pte_alloc_map(mm, pmd, addr);
} else if (sz == PMD_SIZE) {
if (IS_ENABLED(CONFIG_ARCH_WANT_HUGE_PMD_SHARE) &&
pud_none(*pud))
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 7802f216a..ea989d83e 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -35,7 +35,10 @@
#include <linux/efi.h>
#include <linux/swiotlb.h>
+#include <asm/boot.h>
#include <asm/fixmap.h>
+#include <asm/kasan.h>
+#include <asm/kernel-pgtable.h>
#include <asm/memory.h>
#include <asm/sections.h>
#include <asm/setup.h>
@@ -45,7 +48,13 @@
#include "mm.h"
-phys_addr_t memstart_addr __read_mostly = 0;
+/*
+ * We need to be able to catch inadvertent references to memstart_addr
+ * that occur (potentially in generic code) before arm64_memblock_init()
+ * executes, which assigns it its actual value. So use a default value
+ * that cannot be mistaken for a real physical address.
+ */
+s64 memstart_addr __read_mostly = -1;
phys_addr_t arm64_dma_phys_limit __read_mostly;
#ifdef CONFIG_BLK_DEV_INITRD
@@ -58,8 +67,8 @@ static int __init early_initrd(char *p)
if (*endp == ',') {
size = memparse(endp + 1, NULL);
- initrd_start = (unsigned long)__va(start);
- initrd_end = (unsigned long)__va(start + size);
+ initrd_start = start;
+ initrd_end = start + size;
}
return 0;
}
@@ -159,7 +168,57 @@ early_param("mem", early_mem);
void __init arm64_memblock_init(void)
{
- memblock_enforce_memory_limit(memory_limit);
+ const s64 linear_region_size = -(s64)PAGE_OFFSET;
+
+ /*
+ * Ensure that the linear region takes up exactly half of the kernel
+ * virtual address space. This way, we can distinguish a linear address
+ * from a kernel/module/vmalloc address by testing a single bit.
+ */
+ BUILD_BUG_ON(linear_region_size != BIT(VA_BITS - 1));
+
+ /*
+ * Select a suitable value for the base of physical memory.
+ */
+ memstart_addr = round_down(memblock_start_of_DRAM(),
+ ARM64_MEMSTART_ALIGN);
+
+ /*
+ * Remove the memory that we will not be able to cover with the
+ * linear mapping. Take care not to clip the kernel which may be
+ * high in memory.
+ */
+ memblock_remove(max_t(u64, memstart_addr + linear_region_size, __pa(_end)),
+ ULLONG_MAX);
+ if (memblock_end_of_DRAM() > linear_region_size)
+ memblock_remove(0, memblock_end_of_DRAM() - linear_region_size);
+
+ /*
+ * Apply the memory limit if it was set. Since the kernel may be loaded
+ * high up in memory, add back the kernel region that must be accessible
+ * via the linear mapping.
+ */
+ if (memory_limit != (phys_addr_t)ULLONG_MAX) {
+ memblock_enforce_memory_limit(memory_limit);
+ memblock_add(__pa(_text), (u64)(_end - _text));
+ }
+
+ if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
+ extern u16 memstart_offset_seed;
+ u64 range = linear_region_size -
+ (memblock_end_of_DRAM() - memblock_start_of_DRAM());
+
+ /*
+ * If the size of the linear region exceeds, by a sufficient
+ * margin, the size of the region that the available physical
+ * memory spans, randomize the linear region as well.
+ */
+ if (memstart_offset_seed > 0 && range >= ARM64_MEMSTART_ALIGN) {
+ range = range / ARM64_MEMSTART_ALIGN + 1;
+ memstart_addr -= ARM64_MEMSTART_ALIGN *
+ ((range * memstart_offset_seed) >> 16);
+ }
+ }
/*
* Register the kernel text, kernel data, initrd, and initial
@@ -167,8 +226,13 @@ void __init arm64_memblock_init(void)
*/
memblock_reserve(__pa(_text), _end - _text);
#ifdef CONFIG_BLK_DEV_INITRD
- if (initrd_start)
- memblock_reserve(__virt_to_phys(initrd_start), initrd_end - initrd_start);
+ if (initrd_start) {
+ memblock_reserve(initrd_start, initrd_end - initrd_start);
+
+ /* the generic initrd code expects virtual addresses */
+ initrd_start = __phys_to_virt(initrd_start);
+ initrd_end = __phys_to_virt(initrd_end);
+ }
#endif
early_init_fdt_scan_reserved_mem();
@@ -298,39 +362,38 @@ void __init mem_init(void)
#define MLG(b, t) b, t, ((t) - (b)) >> 30
#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
- pr_notice("Virtual kernel memory layout:\n"
-#ifdef CONFIG_KASAN
- " kasan : 0x%16lx - 0x%16lx (%6ld GB)\n"
-#endif
- " vmalloc : 0x%16lx - 0x%16lx (%6ld GB)\n"
-#ifdef CONFIG_SPARSEMEM_VMEMMAP
- " vmemmap : 0x%16lx - 0x%16lx (%6ld GB maximum)\n"
- " 0x%16lx - 0x%16lx (%6ld MB actual)\n"
-#endif
- " fixed : 0x%16lx - 0x%16lx (%6ld KB)\n"
- " PCI I/O : 0x%16lx - 0x%16lx (%6ld MB)\n"
- " modules : 0x%16lx - 0x%16lx (%6ld MB)\n"
- " memory : 0x%16lx - 0x%16lx (%6ld MB)\n"
- " .init : 0x%p" " - 0x%p" " (%6ld KB)\n"
- " .text : 0x%p" " - 0x%p" " (%6ld KB)\n"
- " .data : 0x%p" " - 0x%p" " (%6ld KB)\n",
+ pr_notice("Virtual kernel memory layout:\n");
#ifdef CONFIG_KASAN
- MLG(KASAN_SHADOW_START, KASAN_SHADOW_END),
+ pr_cont(" kasan : 0x%16lx - 0x%16lx (%6ld GB)\n",
+ MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
#endif
- MLG(VMALLOC_START, VMALLOC_END),
+ pr_cont(" modules : 0x%16lx - 0x%16lx (%6ld MB)\n",
+ MLM(MODULES_VADDR, MODULES_END));
+ pr_cont(" vmalloc : 0x%16lx - 0x%16lx (%6ld GB)\n",
+ MLG(VMALLOC_START, VMALLOC_END));
+ pr_cont(" .text : 0x%p" " - 0x%p" " (%6ld KB)\n"
+ " .rodata : 0x%p" " - 0x%p" " (%6ld KB)\n"
+ " .init : 0x%p" " - 0x%p" " (%6ld KB)\n"
+ " .data : 0x%p" " - 0x%p" " (%6ld KB)\n",
+ MLK_ROUNDUP(_text, __start_rodata),
+ MLK_ROUNDUP(__start_rodata, _etext),
+ MLK_ROUNDUP(__init_begin, __init_end),
+ MLK_ROUNDUP(_sdata, _edata));
#ifdef CONFIG_SPARSEMEM_VMEMMAP
- MLG(VMEMMAP_START,
- VMEMMAP_START + VMEMMAP_SIZE),
- MLM((unsigned long)virt_to_page(PAGE_OFFSET),
- (unsigned long)virt_to_page(high_memory)),
+ pr_cont(" vmemmap : 0x%16lx - 0x%16lx (%6ld GB maximum)\n"
+ " 0x%16lx - 0x%16lx (%6ld MB actual)\n",
+ MLG(VMEMMAP_START,
+ VMEMMAP_START + VMEMMAP_SIZE),
+ MLM((unsigned long)phys_to_page(memblock_start_of_DRAM()),
+ (unsigned long)virt_to_page(high_memory)));
#endif
- MLK(FIXADDR_START, FIXADDR_TOP),
- MLM(PCI_IO_START, PCI_IO_END),
- MLM(MODULES_VADDR, MODULES_END),
- MLM(PAGE_OFFSET, (unsigned long)high_memory),
- MLK_ROUNDUP(__init_begin, __init_end),
- MLK_ROUNDUP(_text, _etext),
- MLK_ROUNDUP(_sdata, _edata));
+ pr_cont(" fixed : 0x%16lx - 0x%16lx (%6ld KB)\n",
+ MLK(FIXADDR_START, FIXADDR_TOP));
+ pr_cont(" PCI I/O : 0x%16lx - 0x%16lx (%6ld MB)\n",
+ MLM(PCI_IO_START, PCI_IO_END));
+ pr_cont(" memory : 0x%16lx - 0x%16lx (%6ld MB)\n",
+ MLM(__phys_to_virt(memblock_start_of_DRAM()),
+ (unsigned long)high_memory));
#undef MLK
#undef MLM
@@ -343,8 +406,6 @@ void __init mem_init(void)
#ifdef CONFIG_COMPAT
BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64);
#endif
- BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
- BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
extern int sysctl_overcommit_memory;
@@ -358,8 +419,8 @@ void __init mem_init(void)
void free_initmem(void)
{
- fixup_init();
free_initmem_default(0);
+ fixup_init();
}
#ifdef CONFIG_BLK_DEV_INITRD
@@ -380,3 +441,28 @@ static int __init keepinitrd_setup(char *__unused)
__setup("keepinitrd", keepinitrd_setup);
#endif
+
+/*
+ * Dump out memory limit information on panic.
+ */
+static int dump_mem_limit(struct notifier_block *self, unsigned long v, void *p)
+{
+ if (memory_limit != (phys_addr_t)ULLONG_MAX) {
+ pr_emerg("Memory Limit: %llu MB\n", memory_limit >> 20);
+ } else {
+ pr_emerg("Memory Limit: none\n");
+ }
+ return 0;
+}
+
+static struct notifier_block mem_limit_notifier = {
+ .notifier_call = dump_mem_limit,
+};
+
+static int __init register_mem_limit_dumper(void)
+{
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &mem_limit_notifier);
+ return 0;
+}
+__initcall(register_mem_limit_dumper);
diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
index cab7a5be4..757009daa 100644
--- a/arch/arm64/mm/kasan_init.c
+++ b/arch/arm64/mm/kasan_init.c
@@ -16,9 +16,12 @@
#include <linux/memblock.h>
#include <linux/start_kernel.h>
+#include <asm/mmu_context.h>
+#include <asm/kernel-pgtable.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
+#include <asm/sections.h>
#include <asm/tlbflush.h>
static pgd_t tmp_pg_dir[PTRS_PER_PGD] __initdata __aligned(PGD_SIZE);
@@ -32,7 +35,7 @@ static void __init kasan_early_pte_populate(pmd_t *pmd, unsigned long addr,
if (pmd_none(*pmd))
pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte);
- pte = pte_offset_kernel(pmd, addr);
+ pte = pte_offset_kimg(pmd, addr);
do {
next = addr + PAGE_SIZE;
set_pte(pte, pfn_pte(virt_to_pfn(kasan_zero_page),
@@ -50,7 +53,7 @@ static void __init kasan_early_pmd_populate(pud_t *pud,
if (pud_none(*pud))
pud_populate(&init_mm, pud, kasan_zero_pmd);
- pmd = pmd_offset(pud, addr);
+ pmd = pmd_offset_kimg(pud, addr);
do {
next = pmd_addr_end(addr, end);
kasan_early_pte_populate(pmd, addr, next);
@@ -67,7 +70,7 @@ static void __init kasan_early_pud_populate(pgd_t *pgd,
if (pgd_none(*pgd))
pgd_populate(&init_mm, pgd, kasan_zero_pud);
- pud = pud_offset(pgd, addr);
+ pud = pud_offset_kimg(pgd, addr);
do {
next = pud_addr_end(addr, end);
kasan_early_pmd_populate(pud, addr, next);
@@ -96,6 +99,21 @@ asmlinkage void __init kasan_early_init(void)
kasan_map_early_shadow();
}
+/*
+ * Copy the current shadow region into a new pgdir.
+ */
+void __init kasan_copy_shadow(pgd_t *pgdir)
+{
+ pgd_t *pgd, *pgd_new, *pgd_end;
+
+ pgd = pgd_offset_k(KASAN_SHADOW_START);
+ pgd_end = pgd_offset_k(KASAN_SHADOW_END);
+ pgd_new = pgd_offset_raw(pgdir, KASAN_SHADOW_START);
+ do {
+ set_pgd(pgd_new, *pgd);
+ } while (pgd++, pgd_new++, pgd != pgd_end);
+}
+
static void __init clear_pgds(unsigned long start,
unsigned long end)
{
@@ -108,20 +126,19 @@ static void __init clear_pgds(unsigned long start,
set_pgd(pgd_offset_k(start), __pgd(0));
}
-static void __init cpu_set_ttbr1(unsigned long ttbr1)
-{
- asm(
- " msr ttbr1_el1, %0\n"
- " isb"
- :
- : "r" (ttbr1));
-}
-
void __init kasan_init(void)
{
+ u64 kimg_shadow_start, kimg_shadow_end;
+ u64 mod_shadow_start, mod_shadow_end;
struct memblock_region *reg;
int i;
+ kimg_shadow_start = (u64)kasan_mem_to_shadow(_text);
+ kimg_shadow_end = (u64)kasan_mem_to_shadow(_end);
+
+ mod_shadow_start = (u64)kasan_mem_to_shadow((void *)MODULES_VADDR);
+ mod_shadow_end = (u64)kasan_mem_to_shadow((void *)MODULES_END);
+
/*
* We are going to perform proper setup of shadow memory.
* At first we should unmap early shadow (clear_pgds() call bellow).
@@ -130,13 +147,33 @@ void __init kasan_init(void)
* setup will be finished.
*/
memcpy(tmp_pg_dir, swapper_pg_dir, sizeof(tmp_pg_dir));
- cpu_set_ttbr1(__pa(tmp_pg_dir));
- flush_tlb_all();
+ dsb(ishst);
+ cpu_replace_ttbr1(tmp_pg_dir);
clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END);
+ vmemmap_populate(kimg_shadow_start, kimg_shadow_end,
+ pfn_to_nid(virt_to_pfn(_text)));
+
+ /*
+ * vmemmap_populate() has populated the shadow region that covers the
+ * kernel image with SWAPPER_BLOCK_SIZE mappings, so we have to round
+ * the start and end addresses to SWAPPER_BLOCK_SIZE as well, to prevent
+ * kasan_populate_zero_shadow() from replacing the page table entries
+ * (PMD or PTE) at the edges of the shadow region for the kernel
+ * image.
+ */
+ kimg_shadow_start = round_down(kimg_shadow_start, SWAPPER_BLOCK_SIZE);
+ kimg_shadow_end = round_up(kimg_shadow_end, SWAPPER_BLOCK_SIZE);
+
kasan_populate_zero_shadow((void *)KASAN_SHADOW_START,
- kasan_mem_to_shadow((void *)MODULES_VADDR));
+ (void *)mod_shadow_start);
+ kasan_populate_zero_shadow((void *)kimg_shadow_end,
+ kasan_mem_to_shadow((void *)PAGE_OFFSET));
+
+ if (kimg_shadow_start > mod_shadow_end)
+ kasan_populate_zero_shadow((void *)mod_shadow_end,
+ (void *)kimg_shadow_start);
for_each_memblock(memory, reg) {
void *start = (void *)__phys_to_virt(reg->base);
@@ -165,8 +202,7 @@ void __init kasan_init(void)
pfn_pte(virt_to_pfn(kasan_zero_page), PAGE_KERNEL_RO));
memset(kasan_zero_page, 0, PAGE_SIZE);
- cpu_set_ttbr1(__pa(swapper_pg_dir));
- flush_tlb_all();
+ cpu_replace_ttbr1(swapper_pg_dir);
/* At this point kasan is fully initialized. Enable error messages */
init_task.kasan_depth = 0;
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 58faeaa7f..f3e5c7423 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -30,8 +30,10 @@
#include <linux/slab.h>
#include <linux/stop_machine.h>
+#include <asm/barrier.h>
#include <asm/cputype.h>
#include <asm/fixmap.h>
+#include <asm/kasan.h>
#include <asm/kernel-pgtable.h>
#include <asm/sections.h>
#include <asm/setup.h>
@@ -44,13 +46,20 @@
u64 idmap_t0sz = TCR_T0SZ(VA_BITS);
+u64 kimage_voffset __read_mostly;
+EXPORT_SYMBOL(kimage_voffset);
+
/*
* Empty_zero_page is a special page that is used for zero-initialized data
* and COW.
*/
-struct page *empty_zero_page;
+unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
EXPORT_SYMBOL(empty_zero_page);
+static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss;
+static pmd_t bm_pmd[PTRS_PER_PMD] __page_aligned_bss __maybe_unused;
+static pud_t bm_pud[PTRS_PER_PUD] __page_aligned_bss __maybe_unused;
+
pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot)
{
@@ -62,16 +71,30 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
}
EXPORT_SYMBOL(phys_mem_access_prot);
-static void __init *early_alloc(unsigned long sz)
+static phys_addr_t __init early_pgtable_alloc(void)
{
phys_addr_t phys;
void *ptr;
- phys = memblock_alloc(sz, sz);
+ phys = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
BUG_ON(!phys);
- ptr = __va(phys);
- memset(ptr, 0, sz);
- return ptr;
+
+ /*
+ * 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;
}
/*
@@ -95,24 +118,30 @@ static void split_pmd(pmd_t *pmd, pte_t *pte)
static void alloc_init_pte(pmd_t *pmd, unsigned long addr,
unsigned long end, unsigned long pfn,
pgprot_t prot,
- void *(*alloc)(unsigned long size))
+ phys_addr_t (*pgtable_alloc)(void))
{
pte_t *pte;
if (pmd_none(*pmd) || pmd_sect(*pmd)) {
- pte = alloc(PTRS_PER_PTE * sizeof(pte_t));
+ phys_addr_t pte_phys;
+ BUG_ON(!pgtable_alloc);
+ pte_phys = pgtable_alloc();
+ pte = pte_set_fixmap(pte_phys);
if (pmd_sect(*pmd))
split_pmd(pmd, pte);
- __pmd_populate(pmd, __pa(pte), PMD_TYPE_TABLE);
+ __pmd_populate(pmd, pte_phys, PMD_TYPE_TABLE);
flush_tlb_all();
+ pte_clear_fixmap();
}
BUG_ON(pmd_bad(*pmd));
- pte = pte_offset_kernel(pmd, addr);
+ pte = pte_set_fixmap_offset(pmd, addr);
do {
set_pte(pte, pfn_pte(pfn, prot));
pfn++;
} while (pte++, addr += PAGE_SIZE, addr != end);
+
+ pte_clear_fixmap();
}
static void split_pud(pud_t *old_pud, pmd_t *pmd)
@@ -127,10 +156,29 @@ static void split_pud(pud_t *old_pud, pmd_t *pmd)
} while (pmd++, i++, i < PTRS_PER_PMD);
}
-static void alloc_init_pmd(struct mm_struct *mm, pud_t *pud,
- unsigned long addr, unsigned long end,
+#ifdef CONFIG_DEBUG_PAGEALLOC
+static bool block_mappings_allowed(phys_addr_t (*pgtable_alloc)(void))
+{
+
+ /*
+ * If debug_page_alloc is enabled we must map the linear map
+ * using pages. However, other mappings created by
+ * create_mapping_noalloc must use sections in some cases. Allow
+ * sections to be used in those cases, where no pgtable_alloc
+ * function is provided.
+ */
+ return !pgtable_alloc || !debug_pagealloc_enabled();
+}
+#else
+static bool block_mappings_allowed(phys_addr_t (*pgtable_alloc)(void))
+{
+ return true;
+}
+#endif
+
+static void alloc_init_pmd(pud_t *pud, unsigned long addr, unsigned long end,
phys_addr_t phys, pgprot_t prot,
- void *(*alloc)(unsigned long size))
+ phys_addr_t (*pgtable_alloc)(void))
{
pmd_t *pmd;
unsigned long next;
@@ -139,7 +187,10 @@ static void alloc_init_pmd(struct mm_struct *mm, pud_t *pud,
* Check for initial section mappings in the pgd/pud and remove them.
*/
if (pud_none(*pud) || pud_sect(*pud)) {
- pmd = alloc(PTRS_PER_PMD * sizeof(pmd_t));
+ phys_addr_t pmd_phys;
+ BUG_ON(!pgtable_alloc);
+ pmd_phys = pgtable_alloc();
+ pmd = pmd_set_fixmap(pmd_phys);
if (pud_sect(*pud)) {
/*
* need to have the 1G of mappings continue to be
@@ -147,19 +198,20 @@ static void alloc_init_pmd(struct mm_struct *mm, pud_t *pud,
*/
split_pud(pud, pmd);
}
- pud_populate(mm, pud, pmd);
+ __pud_populate(pud, pmd_phys, PUD_TYPE_TABLE);
flush_tlb_all();
+ pmd_clear_fixmap();
}
BUG_ON(pud_bad(*pud));
- pmd = pmd_offset(pud, addr);
+ pmd = pmd_set_fixmap_offset(pud, addr);
do {
next = pmd_addr_end(addr, end);
/* try section mapping first */
- if (((addr | next | phys) & ~SECTION_MASK) == 0) {
+ if (((addr | next | phys) & ~SECTION_MASK) == 0 &&
+ block_mappings_allowed(pgtable_alloc)) {
pmd_t old_pmd =*pmd;
- set_pmd(pmd, __pmd(phys |
- pgprot_val(mk_sect_prot(prot))));
+ pmd_set_huge(pmd, phys, prot);
/*
* Check for previous table entries created during
* boot (__create_page_tables) and flush them.
@@ -167,17 +219,19 @@ static void alloc_init_pmd(struct mm_struct *mm, pud_t *pud,
if (!pmd_none(old_pmd)) {
flush_tlb_all();
if (pmd_table(old_pmd)) {
- phys_addr_t table = __pa(pte_offset_map(&old_pmd, 0));
+ phys_addr_t table = pmd_page_paddr(old_pmd);
if (!WARN_ON_ONCE(slab_is_available()))
memblock_free(table, PAGE_SIZE);
}
}
} else {
alloc_init_pte(pmd, addr, next, __phys_to_pfn(phys),
- prot, alloc);
+ prot, pgtable_alloc);
}
phys += next - addr;
} while (pmd++, addr = next, addr != end);
+
+ pmd_clear_fixmap();
}
static inline bool use_1G_block(unsigned long addr, unsigned long next,
@@ -192,31 +246,32 @@ static inline bool use_1G_block(unsigned long addr, unsigned long next,
return true;
}
-static void alloc_init_pud(struct mm_struct *mm, pgd_t *pgd,
- unsigned long addr, unsigned long end,
+static void alloc_init_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
phys_addr_t phys, pgprot_t prot,
- void *(*alloc)(unsigned long size))
+ phys_addr_t (*pgtable_alloc)(void))
{
pud_t *pud;
unsigned long next;
if (pgd_none(*pgd)) {
- pud = alloc(PTRS_PER_PUD * sizeof(pud_t));
- pgd_populate(mm, pgd, pud);
+ phys_addr_t pud_phys;
+ BUG_ON(!pgtable_alloc);
+ pud_phys = pgtable_alloc();
+ __pgd_populate(pgd, pud_phys, PUD_TYPE_TABLE);
}
BUG_ON(pgd_bad(*pgd));
- pud = pud_offset(pgd, addr);
+ pud = pud_set_fixmap_offset(pgd, addr);
do {
next = pud_addr_end(addr, end);
/*
* For 4K granule only, attempt to put down a 1GB block
*/
- if (use_1G_block(addr, next, phys)) {
+ if (use_1G_block(addr, next, phys) &&
+ block_mappings_allowed(pgtable_alloc)) {
pud_t old_pud = *pud;
- set_pud(pud, __pud(phys |
- pgprot_val(mk_sect_prot(prot))));
+ pud_set_huge(pud, phys, prot);
/*
* If we have an old value for a pud, it will
@@ -228,26 +283,28 @@ static void alloc_init_pud(struct mm_struct *mm, pgd_t *pgd,
if (!pud_none(old_pud)) {
flush_tlb_all();
if (pud_table(old_pud)) {
- phys_addr_t table = __pa(pmd_offset(&old_pud, 0));
+ phys_addr_t table = pud_page_paddr(old_pud);
if (!WARN_ON_ONCE(slab_is_available()))
memblock_free(table, PAGE_SIZE);
}
}
} else {
- alloc_init_pmd(mm, pud, addr, next, phys, prot, alloc);
+ alloc_init_pmd(pud, addr, next, phys, prot,
+ pgtable_alloc);
}
phys += next - addr;
} while (pud++, addr = next, addr != end);
+
+ pud_clear_fixmap();
}
/*
* Create the page directory entries and any necessary page tables for the
* mapping specified by 'md'.
*/
-static void __create_mapping(struct mm_struct *mm, pgd_t *pgd,
- phys_addr_t phys, unsigned long virt,
+static void init_pgd(pgd_t *pgd, phys_addr_t phys, unsigned long virt,
phys_addr_t size, pgprot_t prot,
- void *(*alloc)(unsigned long size))
+ phys_addr_t (*pgtable_alloc)(void))
{
unsigned long addr, length, end, next;
@@ -265,22 +322,35 @@ static void __create_mapping(struct mm_struct *mm, pgd_t *pgd,
end = addr + length;
do {
next = pgd_addr_end(addr, end);
- alloc_init_pud(mm, pgd, addr, next, phys, prot, alloc);
+ alloc_init_pud(pgd, addr, next, phys, prot, pgtable_alloc);
phys += next - addr;
} while (pgd++, addr = next, addr != end);
}
-static void *late_alloc(unsigned long size)
+static phys_addr_t late_pgtable_alloc(void)
{
- void *ptr;
-
- BUG_ON(size > PAGE_SIZE);
- ptr = (void *)__get_free_page(PGALLOC_GFP);
+ void *ptr = (void *)__get_free_page(PGALLOC_GFP);
BUG_ON(!ptr);
- return ptr;
+
+ /* Ensure the zeroed page is visible to the page table walker */
+ dsb(ishst);
+ return __pa(ptr);
}
-static void __init create_mapping(phys_addr_t phys, unsigned long virt,
+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 (*alloc)(void))
+{
+ init_pgd(pgd_offset_raw(pgdir, virt), phys, virt, size, prot, alloc);
+}
+
+/*
+ * This function can only be used to modify existing table entries,
+ * without allocating new levels of table. Note that this permits the
+ * creation of new section or page entries.
+ */
+static void __init create_mapping_noalloc(phys_addr_t phys, unsigned long virt,
phys_addr_t size, pgprot_t prot)
{
if (virt < VMALLOC_START) {
@@ -288,16 +358,16 @@ static void __init create_mapping(phys_addr_t phys, unsigned long virt,
&phys, virt);
return;
}
- __create_mapping(&init_mm, pgd_offset_k(virt), phys, virt,
- size, prot, early_alloc);
+ __create_pgd_mapping(init_mm.pgd, phys, virt, size, prot,
+ NULL);
}
void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys,
unsigned long virt, phys_addr_t size,
pgprot_t prot)
{
- __create_mapping(mm, pgd_offset(mm, virt), phys, virt, size, prot,
- late_alloc);
+ __create_pgd_mapping(mm->pgd, phys, virt, size, prot,
+ late_pgtable_alloc);
}
static void create_mapping_late(phys_addr_t phys, unsigned long virt,
@@ -309,69 +379,57 @@ static void create_mapping_late(phys_addr_t phys, unsigned long virt,
return;
}
- return __create_mapping(&init_mm, pgd_offset_k(virt),
- phys, virt, size, prot, late_alloc);
+ __create_pgd_mapping(init_mm.pgd, phys, virt, size, prot,
+ late_pgtable_alloc);
}
-#ifdef CONFIG_DEBUG_RODATA
-static void __init __map_memblock(phys_addr_t start, phys_addr_t end)
+static void __init __map_memblock(pgd_t *pgd, phys_addr_t start, phys_addr_t end)
{
+ unsigned long kernel_start = __pa(_stext);
+ unsigned long kernel_end = __pa(_etext);
+
/*
- * Set up the executable regions using the existing section mappings
- * for now. This will get more fine grained later once all memory
- * is mapped
+ * Take care not to create a writable alias for the
+ * read-only text and rodata sections of the kernel image.
*/
- unsigned long kernel_x_start = round_down(__pa(_stext), SWAPPER_BLOCK_SIZE);
- unsigned long kernel_x_end = round_up(__pa(__init_end), SWAPPER_BLOCK_SIZE);
-
- if (end < kernel_x_start) {
- create_mapping(start, __phys_to_virt(start),
- end - start, PAGE_KERNEL);
- } else if (start >= kernel_x_end) {
- create_mapping(start, __phys_to_virt(start),
- end - start, PAGE_KERNEL);
- } else {
- if (start < kernel_x_start)
- create_mapping(start, __phys_to_virt(start),
- kernel_x_start - start,
- PAGE_KERNEL);
- create_mapping(kernel_x_start,
- __phys_to_virt(kernel_x_start),
- kernel_x_end - kernel_x_start,
- PAGE_KERNEL_EXEC);
- if (kernel_x_end < end)
- create_mapping(kernel_x_end,
- __phys_to_virt(kernel_x_end),
- end - kernel_x_end,
- PAGE_KERNEL);
+
+ /* No overlap with the kernel text */
+ if (end < kernel_start || start >= kernel_end) {
+ __create_pgd_mapping(pgd, start, __phys_to_virt(start),
+ end - start, PAGE_KERNEL,
+ early_pgtable_alloc);
+ return;
}
+ /*
+ * This block overlaps the kernel text mapping.
+ * Map the portion(s) which don't overlap.
+ */
+ if (start < kernel_start)
+ __create_pgd_mapping(pgd, start,
+ __phys_to_virt(start),
+ kernel_start - start, PAGE_KERNEL,
+ early_pgtable_alloc);
+ if (kernel_end < end)
+ __create_pgd_mapping(pgd, kernel_end,
+ __phys_to_virt(kernel_end),
+ end - kernel_end, PAGE_KERNEL,
+ early_pgtable_alloc);
+
+ /*
+ * Map the linear alias of the [_stext, _etext) interval as
+ * read-only/non-executable. This makes the contents of the
+ * region accessible to subsystems such as hibernate, but
+ * protects it from inadvertent modification or execution.
+ */
+ __create_pgd_mapping(pgd, kernel_start, __phys_to_virt(kernel_start),
+ kernel_end - kernel_start, PAGE_KERNEL_RO,
+ early_pgtable_alloc);
}
-#else
-static void __init __map_memblock(phys_addr_t start, phys_addr_t end)
-{
- create_mapping(start, __phys_to_virt(start), end - start,
- PAGE_KERNEL_EXEC);
-}
-#endif
-static void __init map_mem(void)
+static void __init map_mem(pgd_t *pgd)
{
struct memblock_region *reg;
- phys_addr_t limit;
-
- /*
- * Temporarily limit the memblock range. We need to do this as
- * create_mapping requires puds, pmds and ptes to be allocated from
- * memory addressable from the initial direct kernel mapping.
- *
- * The initial direct kernel mapping, located at swapper_pg_dir, gives
- * us PUD_SIZE (with SECTION maps) or PMD_SIZE (without SECTION maps,
- * memory starting from PHYS_OFFSET (which must be aligned to 2MB as
- * per Documentation/arm64/booting.txt).
- */
- limit = PHYS_OFFSET + SWAPPER_INIT_MAP_SIZE;
- memblock_set_current_limit(limit);
/* map all the memory banks */
for_each_memblock(memory, reg) {
@@ -383,69 +441,94 @@ static void __init map_mem(void)
if (memblock_is_nomap(reg))
continue;
- if (ARM64_SWAPPER_USES_SECTION_MAPS) {
- /*
- * For the first memory bank align the start address and
- * current memblock limit to prevent create_mapping() from
- * allocating pte page tables from unmapped memory. With
- * the section maps, if the first block doesn't end on section
- * size boundary, create_mapping() will try to allocate a pte
- * page, which may be returned from an unmapped area.
- * When section maps are not used, the pte page table for the
- * current limit is already present in swapper_pg_dir.
- */
- if (start < limit)
- start = ALIGN(start, SECTION_SIZE);
- if (end < limit) {
- limit = end & SECTION_MASK;
- memblock_set_current_limit(limit);
- }
- }
- __map_memblock(start, end);
+ __map_memblock(pgd, start, end);
}
-
- /* Limit no longer required. */
- memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE);
}
-static void __init fixup_executable(void)
+void mark_rodata_ro(void)
{
-#ifdef CONFIG_DEBUG_RODATA
- /* now that we are actually fully mapped, make the start/end more fine grained */
- if (!IS_ALIGNED((unsigned long)_stext, SWAPPER_BLOCK_SIZE)) {
- unsigned long aligned_start = round_down(__pa(_stext),
- SWAPPER_BLOCK_SIZE);
+ unsigned long section_size;
- create_mapping(aligned_start, __phys_to_virt(aligned_start),
- __pa(_stext) - aligned_start,
- PAGE_KERNEL);
- }
+ section_size = (unsigned long)__start_rodata - (unsigned long)_stext;
+ create_mapping_late(__pa(_stext), (unsigned long)_stext,
+ section_size, PAGE_KERNEL_ROX);
+ /*
+ * mark .rodata as read only. Use _etext rather than __end_rodata to
+ * cover NOTES and EXCEPTION_TABLE.
+ */
+ section_size = (unsigned long)_etext - (unsigned long)__start_rodata;
+ create_mapping_late(__pa(__start_rodata), (unsigned long)__start_rodata,
+ section_size, PAGE_KERNEL_RO);
+}
- if (!IS_ALIGNED((unsigned long)__init_end, SWAPPER_BLOCK_SIZE)) {
- unsigned long aligned_end = round_up(__pa(__init_end),
- SWAPPER_BLOCK_SIZE);
- create_mapping(__pa(__init_end), (unsigned long)__init_end,
- aligned_end - __pa(__init_end),
- PAGE_KERNEL);
- }
-#endif
+void fixup_init(void)
+{
+ /*
+ * Unmap the __init region but leave the VM area in place. This
+ * prevents the region from being reused for kernel modules, which
+ * is not supported by kallsyms.
+ */
+ unmap_kernel_range((u64)__init_begin, (u64)(__init_end - __init_begin));
}
-#ifdef CONFIG_DEBUG_RODATA
-void mark_rodata_ro(void)
+static void __init map_kernel_chunk(pgd_t *pgd, void *va_start, void *va_end,
+ pgprot_t prot, struct vm_struct *vma)
{
- create_mapping_late(__pa(_stext), (unsigned long)_stext,
- (unsigned long)_etext - (unsigned long)_stext,
- PAGE_KERNEL_ROX);
+ phys_addr_t pa_start = __pa(va_start);
+ unsigned long size = va_end - va_start;
+
+ BUG_ON(!PAGE_ALIGNED(pa_start));
+ BUG_ON(!PAGE_ALIGNED(size));
+
+ __create_pgd_mapping(pgd, pa_start, (unsigned long)va_start, size, prot,
+ early_pgtable_alloc);
+
+ vma->addr = va_start;
+ vma->phys_addr = pa_start;
+ vma->size = size;
+ vma->flags = VM_MAP;
+ vma->caller = __builtin_return_address(0);
+ vm_area_add_early(vma);
}
-#endif
-void fixup_init(void)
+/*
+ * Create fine-grained mappings for the kernel.
+ */
+static void __init map_kernel(pgd_t *pgd)
{
- create_mapping_late(__pa(__init_begin), (unsigned long)__init_begin,
- (unsigned long)__init_end - (unsigned long)__init_begin,
- PAGE_KERNEL);
+ static struct vm_struct vmlinux_text, vmlinux_rodata, vmlinux_init, vmlinux_data;
+
+ map_kernel_chunk(pgd, _stext, __start_rodata, PAGE_KERNEL_EXEC, &vmlinux_text);
+ map_kernel_chunk(pgd, __start_rodata, _etext, PAGE_KERNEL, &vmlinux_rodata);
+ map_kernel_chunk(pgd, __init_begin, __init_end, PAGE_KERNEL_EXEC,
+ &vmlinux_init);
+ map_kernel_chunk(pgd, _data, _end, PAGE_KERNEL, &vmlinux_data);
+
+ if (!pgd_val(*pgd_offset_raw(pgd, FIXADDR_START))) {
+ /*
+ * The fixmap falls in a separate pgd to the kernel, and doesn't
+ * live in the carveout for the swapper_pg_dir. We can simply
+ * re-use the existing dir for the fixmap.
+ */
+ set_pgd(pgd_offset_raw(pgd, FIXADDR_START),
+ *pgd_offset_k(FIXADDR_START));
+ } else if (CONFIG_PGTABLE_LEVELS > 3) {
+ /*
+ * The fixmap shares its top level pgd entry with the kernel
+ * mapping. This can really only occur when we are running
+ * with 16k/4 levels, so we can simply reuse the pud level
+ * entry instead.
+ */
+ BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
+ set_pud(pud_set_fixmap_offset(pgd, FIXADDR_START),
+ __pud(__pa(bm_pmd) | PUD_TYPE_TABLE));
+ pud_clear_fixmap();
+ } else {
+ BUG();
+ }
+
+ kasan_copy_shadow(pgd);
}
/*
@@ -454,28 +537,35 @@ void fixup_init(void)
*/
void __init paging_init(void)
{
- void *zero_page;
+ phys_addr_t pgd_phys = early_pgtable_alloc();
+ pgd_t *pgd = pgd_set_fixmap(pgd_phys);
- map_mem();
- fixup_executable();
+ map_kernel(pgd);
+ map_mem(pgd);
- /* allocate the zero page. */
- zero_page = early_alloc(PAGE_SIZE);
-
- bootmem_init();
-
- empty_zero_page = virt_to_page(zero_page);
+ /*
+ * We want to reuse the original swapper_pg_dir so we don't have to
+ * communicate the new address to non-coherent secondaries in
+ * secondary_entry, and so cpu_switch_mm can generate the address with
+ * adrp+add rather than a load from some global variable.
+ *
+ * To do this we need to go via a temporary pgd.
+ */
+ cpu_replace_ttbr1(__va(pgd_phys));
+ memcpy(swapper_pg_dir, pgd, PAGE_SIZE);
+ cpu_replace_ttbr1(swapper_pg_dir);
- /* Ensure the zero page is visible to the page table walker */
- dsb(ishst);
+ pgd_clear_fixmap();
+ memblock_free(pgd_phys, PAGE_SIZE);
/*
- * TTBR0 is only used for the identity mapping at this stage. Make it
- * point to zero page to avoid speculatively fetching new entries.
+ * We only reuse the PGD from the swapper_pg_dir, not the pud + pmd
+ * allocated with it.
*/
- cpu_set_reserved_ttbr0();
- local_flush_tlb_all();
- cpu_set_default_tcr_t0sz();
+ memblock_free(__pa(swapper_pg_dir) + PAGE_SIZE,
+ SWAPPER_DIR_SIZE - PAGE_SIZE);
+
+ bootmem_init();
}
/*
@@ -562,21 +652,13 @@ void vmemmap_free(unsigned long start, unsigned long end)
}
#endif /* CONFIG_SPARSEMEM_VMEMMAP */
-static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss;
-#if CONFIG_PGTABLE_LEVELS > 2
-static pmd_t bm_pmd[PTRS_PER_PMD] __page_aligned_bss;
-#endif
-#if CONFIG_PGTABLE_LEVELS > 3
-static pud_t bm_pud[PTRS_PER_PUD] __page_aligned_bss;
-#endif
-
static inline pud_t * fixmap_pud(unsigned long addr)
{
pgd_t *pgd = pgd_offset_k(addr);
BUG_ON(pgd_none(*pgd) || pgd_bad(*pgd));
- return pud_offset(pgd, addr);
+ return pud_offset_kimg(pgd, addr);
}
static inline pmd_t * fixmap_pmd(unsigned long addr)
@@ -585,16 +667,12 @@ static inline pmd_t * fixmap_pmd(unsigned long addr)
BUG_ON(pud_none(*pud) || pud_bad(*pud));
- return pmd_offset(pud, addr);
+ return pmd_offset_kimg(pud, addr);
}
static inline pte_t * fixmap_pte(unsigned long addr)
{
- pmd_t *pmd = fixmap_pmd(addr);
-
- BUG_ON(pmd_none(*pmd) || pmd_bad(*pmd));
-
- return pte_offset_kernel(pmd, addr);
+ return &bm_pte[pte_index(addr)];
}
void __init early_fixmap_init(void)
@@ -605,15 +683,26 @@ void __init early_fixmap_init(void)
unsigned long addr = FIXADDR_START;
pgd = pgd_offset_k(addr);
- pgd_populate(&init_mm, pgd, bm_pud);
- pud = pud_offset(pgd, addr);
+ if (CONFIG_PGTABLE_LEVELS > 3 &&
+ !(pgd_none(*pgd) || pgd_page_paddr(*pgd) == __pa(bm_pud))) {
+ /*
+ * We only end up here if the kernel mapping and the fixmap
+ * share the top level pgd entry, which should only happen on
+ * 16k/4 levels configurations.
+ */
+ BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
+ pud = pud_offset_kimg(pgd, addr);
+ } else {
+ pgd_populate(&init_mm, pgd, bm_pud);
+ pud = fixmap_pud(addr);
+ }
pud_populate(&init_mm, pud, bm_pmd);
- pmd = pmd_offset(pud, addr);
+ pmd = fixmap_pmd(addr);
pmd_populate_kernel(&init_mm, pmd, bm_pte);
/*
* The boot-ioremap range spans multiple pmds, for which
- * we are not preparted:
+ * we are not prepared:
*/
BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
!= (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
@@ -652,11 +741,10 @@ void __set_fixmap(enum fixed_addresses idx,
}
}
-void *__init fixmap_remap_fdt(phys_addr_t dt_phys)
+void *__init __fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
{
const u64 dt_virt_base = __fix_to_virt(FIX_FDT);
- pgprot_t prot = PAGE_KERNEL_RO;
- int size, offset;
+ int offset;
void *dt_virt;
/*
@@ -673,7 +761,7 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys)
/*
* Make sure that the FDT region can be mapped without the need to
* allocate additional translation table pages, so that it is safe
- * to call create_mapping() this early.
+ * to call create_mapping_noalloc() this early.
*
* On 64k pages, the FDT will be mapped using PTEs, so we need to
* be in the same PMD as the rest of the fixmap.
@@ -689,21 +777,73 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys)
dt_virt = (void *)dt_virt_base + offset;
/* map the first chunk so we can read the size from the header */
- create_mapping(round_down(dt_phys, SWAPPER_BLOCK_SIZE), dt_virt_base,
- SWAPPER_BLOCK_SIZE, prot);
+ create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE),
+ dt_virt_base, SWAPPER_BLOCK_SIZE, prot);
if (fdt_check_header(dt_virt) != 0)
return NULL;
- size = fdt_totalsize(dt_virt);
- if (size > MAX_FDT_SIZE)
+ *size = fdt_totalsize(dt_virt);
+ if (*size > MAX_FDT_SIZE)
return NULL;
- if (offset + size > SWAPPER_BLOCK_SIZE)
- create_mapping(round_down(dt_phys, SWAPPER_BLOCK_SIZE), dt_virt_base,
- round_up(offset + size, SWAPPER_BLOCK_SIZE), prot);
+ if (offset + *size > SWAPPER_BLOCK_SIZE)
+ create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE), dt_virt_base,
+ round_up(offset + *size, SWAPPER_BLOCK_SIZE), prot);
- memblock_reserve(dt_phys, size);
+ return dt_virt;
+}
+
+void *__init fixmap_remap_fdt(phys_addr_t dt_phys)
+{
+ void *dt_virt;
+ int size;
+
+ dt_virt = __fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL_RO);
+ if (!dt_virt)
+ return NULL;
+ memblock_reserve(dt_phys, size);
return dt_virt;
}
+
+int __init arch_ioremap_pud_supported(void)
+{
+ /* only 4k granule supports level 1 block mappings */
+ return IS_ENABLED(CONFIG_ARM64_4K_PAGES);
+}
+
+int __init arch_ioremap_pmd_supported(void)
+{
+ return 1;
+}
+
+int pud_set_huge(pud_t *pud, phys_addr_t phys, pgprot_t prot)
+{
+ BUG_ON(phys & ~PUD_MASK);
+ set_pud(pud, __pud(phys | PUD_TYPE_SECT | pgprot_val(mk_sect_prot(prot))));
+ return 1;
+}
+
+int pmd_set_huge(pmd_t *pmd, phys_addr_t phys, pgprot_t prot)
+{
+ BUG_ON(phys & ~PMD_MASK);
+ set_pmd(pmd, __pmd(phys | PMD_TYPE_SECT | pgprot_val(mk_sect_prot(prot))));
+ return 1;
+}
+
+int pud_clear_huge(pud_t *pud)
+{
+ if (!pud_sect(*pud))
+ return 0;
+ pud_clear(pud);
+ return 1;
+}
+
+int pmd_clear_huge(pmd_t *pmd)
+{
+ if (!pmd_sect(*pmd))
+ return 0;
+ pmd_clear(pmd);
+ return 1;
+}
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index 0795c3a36..ca6d268e3 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c
@@ -37,14 +37,31 @@ static int change_page_range(pte_t *ptep, pgtable_t token, unsigned long addr,
return 0;
}
+/*
+ * This function assumes that the range is mapped with PAGE_SIZE pages.
+ */
+static int __change_memory_common(unsigned long start, unsigned long size,
+ pgprot_t set_mask, pgprot_t clear_mask)
+{
+ struct page_change_data data;
+ int ret;
+
+ data.set_mask = set_mask;
+ data.clear_mask = clear_mask;
+
+ ret = apply_to_page_range(&init_mm, start, size, change_page_range,
+ &data);
+
+ flush_tlb_kernel_range(start, start + size);
+ return ret;
+}
+
static int change_memory_common(unsigned long addr, int numpages,
pgprot_t set_mask, pgprot_t clear_mask)
{
unsigned long start = addr;
unsigned long size = PAGE_SIZE*numpages;
unsigned long end = start + size;
- int ret;
- struct page_change_data data;
struct vm_struct *area;
if (!PAGE_ALIGNED(addr)) {
@@ -75,14 +92,7 @@ static int change_memory_common(unsigned long addr, int numpages,
if (!numpages)
return 0;
- data.set_mask = set_mask;
- data.clear_mask = clear_mask;
-
- ret = apply_to_page_range(&init_mm, start, size, change_page_range,
- &data);
-
- flush_tlb_kernel_range(start, end);
- return ret;
+ return __change_memory_common(start, size, set_mask, clear_mask);
}
int set_memory_ro(unsigned long addr, int numpages)
@@ -114,3 +124,19 @@ int set_memory_x(unsigned long addr, int numpages)
__pgprot(PTE_PXN));
}
EXPORT_SYMBOL_GPL(set_memory_x);
+
+#ifdef CONFIG_DEBUG_PAGEALLOC
+void __kernel_map_pages(struct page *page, int numpages, int enable)
+{
+ unsigned long addr = (unsigned long) page_address(page);
+
+ if (enable)
+ __change_memory_common(addr, PAGE_SIZE * numpages,
+ __pgprot(PTE_VALID),
+ __pgprot(0));
+ else
+ __change_memory_common(addr, PAGE_SIZE * numpages,
+ __pgprot(0),
+ __pgprot(PTE_VALID));
+}
+#endif
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index c164d2cb3..543f51980 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -25,6 +25,8 @@
#include <asm/hwcap.h>
#include <asm/pgtable-hwdef.h>
#include <asm/pgtable.h>
+#include <asm/cpufeature.h>
+#include <asm/alternative.h>
#include "proc-macros.S"
@@ -137,9 +139,47 @@ ENTRY(cpu_do_switch_mm)
bfi x0, x1, #48, #16 // set the ASID
msr ttbr0_el1, x0 // set TTBR0
isb
+alternative_if_not ARM64_WORKAROUND_CAVIUM_27456
ret
+ nop
+ nop
+ nop
+alternative_else
+ ic iallu
+ dsb nsh
+ isb
+ ret
+alternative_endif
ENDPROC(cpu_do_switch_mm)
+ .pushsection ".idmap.text", "ax"
+/*
+ * void idmap_cpu_replace_ttbr1(phys_addr_t new_pgd)
+ *
+ * This is the low-level counterpart to cpu_replace_ttbr1, and should not be
+ * called by anything else. It can only be executed from a TTBR0 mapping.
+ */
+ENTRY(idmap_cpu_replace_ttbr1)
+ mrs x2, daif
+ msr daifset, #0xf
+
+ adrp x1, empty_zero_page
+ msr ttbr1_el1, x1
+ isb
+
+ tlbi vmalle1
+ dsb nsh
+ isb
+
+ msr ttbr1_el1, x0
+ isb
+
+ msr daif, x2
+
+ ret
+ENDPROC(idmap_cpu_replace_ttbr1)
+ .popsection
+
/*
* __cpu_setup
*
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-16 22:23:55 +0000