Contributors: 49
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Ard Biesheuvel |
420 |
24.29% |
20 |
15.62% |
| Catalin Marinas |
379 |
21.92% |
13 |
10.16% |
| Mark Rutland |
300 |
17.35% |
7 |
5.47% |
| Mike Rapoport |
170 |
9.83% |
10 |
7.81% |
| Nicolas Saenz Julienne |
56 |
3.24% |
4 |
3.12% |
| Ganapatrao Kulkarni |
44 |
2.54% |
1 |
0.78% |
| AKASHI Takahiro |
39 |
2.26% |
2 |
1.56% |
| Steve Capper |
35 |
2.02% |
5 |
3.91% |
| Anshuman Khandual |
31 |
1.79% |
6 |
4.69% |
| Baoquan He |
27 |
1.56% |
4 |
3.12% |
| Marc Zyngier |
20 |
1.16% |
2 |
1.56% |
| Chen Zhou |
19 |
1.10% |
1 |
0.78% |
| Greg Hackmann |
17 |
0.98% |
1 |
0.78% |
| JiSheng Zhang |
16 |
0.93% |
4 |
3.12% |
| Florian Fainelli |
13 |
0.75% |
1 |
0.78% |
| Laura Abbott |
12 |
0.69% |
2 |
1.56% |
| Vladimir Murzin |
11 |
0.64% |
1 |
0.78% |
| Will Deacon |
11 |
0.64% |
4 |
3.12% |
| Kristina Martšenko |
10 |
0.58% |
1 |
0.78% |
| Christoph Hellwig |
9 |
0.52% |
5 |
3.91% |
| Miles Chen |
8 |
0.46% |
2 |
1.56% |
| Kefeng Wang |
8 |
0.46% |
2 |
1.56% |
| Andrey Ryabinin |
6 |
0.35% |
1 |
0.78% |
| Suzuki K. Poulose |
6 |
0.35% |
2 |
1.56% |
| Barry Song |
5 |
0.29% |
1 |
0.78% |
| Mark Brown |
4 |
0.23% |
2 |
1.56% |
| Björn Andersson |
4 |
0.23% |
1 |
0.78% |
| Zhen Lei |
4 |
0.23% |
2 |
1.56% |
| Marek Szyprowski |
3 |
0.17% |
1 |
0.78% |
| Stefan Agner |
3 |
0.17% |
1 |
0.78% |
| Tomasz Nowicki |
3 |
0.17% |
1 |
0.78% |
| Mark Salter |
3 |
0.17% |
1 |
0.78% |
| Andre Przywara |
3 |
0.17% |
1 |
0.78% |
| Chenwandun |
3 |
0.17% |
1 |
0.78% |
| Andrew Scull |
3 |
0.17% |
1 |
0.78% |
| Quentin Perret |
3 |
0.17% |
1 |
0.78% |
| Andrew Morton |
3 |
0.17% |
1 |
0.78% |
| Ma Wupeng |
2 |
0.12% |
1 |
0.78% |
| Thomas Gleixner |
2 |
0.12% |
1 |
0.78% |
| Jiang Liu |
2 |
0.12% |
1 |
0.78% |
| Atish Patra |
2 |
0.12% |
1 |
0.78% |
| Vijay Balakrishna |
2 |
0.12% |
1 |
0.78% |
| Christian Bornträger |
2 |
0.12% |
1 |
0.78% |
| Yueyi Li |
1 |
0.06% |
1 |
0.78% |
| Masahiro Yamada |
1 |
0.06% |
1 |
0.78% |
| Dennis Chen |
1 |
0.06% |
1 |
0.78% |
| Rob Herring |
1 |
0.06% |
1 |
0.78% |
| Peng Fan |
1 |
0.06% |
1 |
0.78% |
| Nicholas Piggin |
1 |
0.06% |
1 |
0.78% |
| Total |
1729 |
|
128 |
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Based on arch/arm/mm/init.c
*
* Copyright (C) 1995-2005 Russell King
* Copyright (C) 2012 ARM Ltd.
*/
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/errno.h>
#include <linux/swap.h>
#include <linux/init.h>
#include <linux/cache.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
#include <linux/initrd.h>
#include <linux/gfp.h>
#include <linux/math.h>
#include <linux/memblock.h>
#include <linux/sort.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/dma-direct.h>
#include <linux/dma-map-ops.h>
#include <linux/efi.h>
#include <linux/swiotlb.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/kexec.h>
#include <linux/crash_dump.h>
#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>
#include <asm/kasan.h>
#include <asm/kernel-pgtable.h>
#include <asm/kvm_host.h>
#include <asm/memory.h>
#include <asm/numa.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <linux/sizes.h>
#include <asm/tlb.h>
#include <asm/alternative.h>
#include <asm/xen/swiotlb-xen.h>
/*
* 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 __ro_after_init = -1;
EXPORT_SYMBOL(memstart_addr);
/*
* If the corresponding config options are enabled, we create both ZONE_DMA
* and ZONE_DMA32. By default ZONE_DMA covers the 32-bit addressable memory
* unless restricted on specific platforms (e.g. 30-bit on Raspberry Pi 4).
* In such case, ZONE_DMA32 covers the rest of the 32-bit addressable memory,
* otherwise it is empty.
*/
phys_addr_t __ro_after_init arm64_dma_phys_limit;
/*
* To make optimal use of block mappings when laying out the linear
* mapping, round down the base of physical memory to a size that can
* be mapped efficiently, i.e., either PUD_SIZE (4k granule) or PMD_SIZE
* (64k granule), or a multiple that can be mapped using contiguous bits
* in the page tables: 32 * PMD_SIZE (16k granule)
*/
#if defined(CONFIG_ARM64_4K_PAGES)
#define ARM64_MEMSTART_SHIFT PUD_SHIFT
#elif defined(CONFIG_ARM64_16K_PAGES)
#define ARM64_MEMSTART_SHIFT CONT_PMD_SHIFT
#else
#define ARM64_MEMSTART_SHIFT PMD_SHIFT
#endif
/*
* sparsemem vmemmap imposes an additional requirement on the alignment of
* memstart_addr, due to the fact that the base of the vmemmap region
* has a direct correspondence, and needs to appear sufficiently aligned
* in the virtual address space.
*/
#if ARM64_MEMSTART_SHIFT < SECTION_SIZE_BITS
#define ARM64_MEMSTART_ALIGN (1UL << SECTION_SIZE_BITS)
#else
#define ARM64_MEMSTART_ALIGN (1UL << ARM64_MEMSTART_SHIFT)
#endif
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(),
&crash_size, &crash_base,
&low_size, &high);
if (ret)
return;
reserve_crashkernel_generic(cmdline, 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)
{
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;
}
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);
#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);
max_zone_pfns[ZONE_DMA] = PFN_DOWN(arm64_dma_phys_limit);
#endif
#ifdef CONFIG_ZONE_DMA32
max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
if (!arm64_dma_phys_limit)
arm64_dma_phys_limit = dma32_phys_limit;
#endif
if (!arm64_dma_phys_limit)
arm64_dma_phys_limit = PHYS_MASK + 1;
max_zone_pfns[ZONE_NORMAL] = max_pfn;
free_area_init(max_zone_pfns);
}
int pfn_is_map_memory(unsigned long pfn)
{
phys_addr_t addr = PFN_PHYS(pfn);
/* avoid false positives for bogus PFNs, see comment in pfn_valid() */
if (PHYS_PFN(addr) != pfn)
return 0;
return memblock_is_map_memory(addr);
}
EXPORT_SYMBOL(pfn_is_map_memory);
static phys_addr_t memory_limit __ro_after_init = PHYS_ADDR_MAX;
/*
* Limit the memory size that was specified via FDT.
*/
static int __init early_mem(char *p)
{
if (!p)
return 1;
memory_limit = memparse(p, &p) & PAGE_MASK;
pr_notice("Memory limited to %lldMB\n", memory_limit >> 20);
return 0;
}
early_param("mem", early_mem);
void __init arm64_memblock_init(void)
{
s64 linear_region_size = PAGE_END - _PAGE_OFFSET(vabits_actual);
/*
* Corner case: 52-bit VA capable systems running KVM in nVHE mode may
* be limited in their ability to support a linear map that exceeds 51
* bits of VA space, depending on the placement of the ID map. Given
* that the placement of the ID map may be randomized, let's simply
* limit the kernel's linear map to 51 bits as well if we detect this
* configuration.
*/
if (IS_ENABLED(CONFIG_KVM) && vabits_actual == 52 &&
is_hyp_mode_available() && !is_kernel_in_hyp_mode()) {
pr_info("Capping linear region to 51 bits for KVM in nVHE mode on LVA capable hardware.\n");
linear_region_size = min_t(u64, linear_region_size, BIT(51));
}
/* Remove memory above our supported physical address size */
memblock_remove(1ULL << PHYS_MASK_SHIFT, ULLONG_MAX);
/*
* Select a suitable value for the base of physical memory.
*/
memstart_addr = round_down(memblock_start_of_DRAM(),
ARM64_MEMSTART_ALIGN);
if ((memblock_end_of_DRAM() - memstart_addr) > linear_region_size)
pr_warn("Memory doesn't fit in the linear mapping, VA_BITS too small\n");
/*
* 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_symbol(_end)), ULLONG_MAX);
if (memstart_addr + linear_region_size < memblock_end_of_DRAM()) {
/* ensure that memstart_addr remains sufficiently aligned */
memstart_addr = round_up(memblock_end_of_DRAM() - linear_region_size,
ARM64_MEMSTART_ALIGN);
memblock_remove(0, memstart_addr);
}
/*
* If we are running with a 52-bit kernel VA config on a system that
* does not support it, we have to place the available physical
* memory in the 48-bit addressable part of the linear region, i.e.,
* we have to move it upward. Since memstart_addr represents the
* physical address of PAGE_OFFSET, we have to *subtract* from it.
*/
if (IS_ENABLED(CONFIG_ARM64_VA_BITS_52) && (vabits_actual != 52))
memstart_addr -= _PAGE_OFFSET(vabits_actual) - _PAGE_OFFSET(52);
/*
* 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_MAX) {
memblock_mem_limit_remove_map(memory_limit);
memblock_add(__pa_symbol(_text), (u64)(_end - _text));
}
if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && phys_initrd_size) {
/*
* Add back the memory we just removed if it results in the
* initrd to become inaccessible via the linear mapping.
* Otherwise, this is a no-op
*/
u64 base = phys_initrd_start & PAGE_MASK;
u64 size = PAGE_ALIGN(phys_initrd_start + phys_initrd_size) - base;
/*
* We can only add back the initrd memory if we don't end up
* with more memory than we can address via the linear mapping.
* It is up to the bootloader to position the kernel and the
* initrd reasonably close to each other (i.e., within 32 GB of
* each other) so that all granule/#levels combinations can
* always access both.
*/
if (WARN(base < memblock_start_of_DRAM() ||
base + size > memblock_start_of_DRAM() +
linear_region_size,
"initrd not fully accessible via the linear mapping -- please check your bootloader ...\n")) {
phys_initrd_size = 0;
} else {
memblock_add(base, size);
memblock_clear_nomap(base, size);
memblock_reserve(base, size);
}
}
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.
*/
memblock_reserve(__pa_symbol(_stext), _end - _stext);
if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && phys_initrd_size) {
/* the generic initrd code expects virtual addresses */
initrd_start = __phys_to_virt(phys_initrd_start);
initrd_end = initrd_start + phys_initrd_size;
}
early_init_fdt_scan_reserved_mem();
high_memory = __va(memblock_end_of_DRAM() - 1) + 1;
}
void __init bootmem_init(void)
{
unsigned long min, max;
min = PFN_UP(memblock_start_of_DRAM());
max = PFN_DOWN(memblock_end_of_DRAM());
early_memtest(min << PAGE_SHIFT, max << PAGE_SHIFT);
max_pfn = max_low_pfn = max;
min_low_pfn = min;
arch_numa_init();
/*
* must be done after arch_numa_init() which calls numa_init() to
* initialize node_online_map that gets used in hugetlb_cma_reserve()
* while allocating required CMA size across online nodes.
*/
#if defined(CONFIG_HUGETLB_PAGE) && defined(CONFIG_CMA)
arm64_hugetlb_cma_reserve();
#endif
kvm_hyp_reserve();
/*
* sparse_init() tries to allocate memory from memblock, so must be
* done after the fixed reservations
*/
sparse_init();
zone_sizes_init();
/*
* Reserve the CMA area after arm64_dma_phys_limit was initialised.
*/
dma_contiguous_reserve(arm64_dma_phys_limit);
/*
* request_standard_resources() depends on crashkernel's memory being
* reserved, so do it here.
*/
arch_reserve_crashkernel();
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)
{
bool swiotlb = max_pfn > PFN_DOWN(arm64_dma_phys_limit);
if (IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC) && !swiotlb) {
/*
* If no bouncing needed for ZONE_DMA, reduce the swiotlb
* buffer for kmalloc() bouncing to 1MB per 1GB of RAM.
*/
unsigned long size =
DIV_ROUND_UP(memblock_phys_mem_size(), 1024);
swiotlb_adjust_size(min(swiotlb_size_or_default(), size));
swiotlb = true;
}
swiotlb_init(swiotlb, SWIOTLB_VERBOSE);
/* this will put all unused low memory onto the freelists */
memblock_free_all();
/*
* Check boundaries twice: Some fundamental inconsistencies can be
* detected at build time already.
*/
#ifdef CONFIG_COMPAT
BUILD_BUG_ON(TASK_SIZE_32 > DEFAULT_MAP_WINDOW_64);
#endif
/*
* Selected page table levels should match when derived from
* scratch using the virtual address range and page size.
*/
BUILD_BUG_ON(ARM64_HW_PGTABLE_LEVELS(CONFIG_ARM64_VA_BITS) !=
CONFIG_PGTABLE_LEVELS);
if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
extern int sysctl_overcommit_memory;
/*
* On a machine this small we won't get anywhere without
* overcommit, so turn it on by default.
*/
sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
}
}
void free_initmem(void)
{
free_reserved_area(lm_alias(__init_begin),
lm_alias(__init_end),
POISON_FREE_INITMEM, "unused kernel");
/*
* 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.
*/
vunmap_range((u64)__init_begin, (u64)__init_end);
}
void dump_mem_limit(void)
{
if (memory_limit != PHYS_ADDR_MAX) {
pr_emerg("Memory Limit: %llu MB\n", memory_limit >> 20);
} else {
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 */