aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/vmlinux.lds.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/vmlinux.lds.S')
-rw-r--r--arch/x86/kernel/vmlinux.lds.S247
1 files changed, 95 insertions, 152 deletions
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 78d185d797d..f3f2104408d 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -41,16 +41,41 @@ ENTRY(phys_startup_64)
jiffies_64 = jiffies;
#endif
+#if defined(CONFIG_X86_64) && defined(CONFIG_DEBUG_RODATA)
+/*
+ * On 64-bit, align RODATA to 2MB so that even with CONFIG_DEBUG_RODATA
+ * we retain large page mappings for boundaries spanning kernel text, rodata
+ * and data sections.
+ *
+ * However, kernel identity mappings will have different RWX permissions
+ * to the pages mapping to text and to the pages padding (which are freed) the
+ * text section. Hence kernel identity mappings will be broken to smaller
+ * pages. For 64-bit, kernel text and kernel identity mappings are different,
+ * so we can enable protection checks that come with CONFIG_DEBUG_RODATA,
+ * as well as retain 2MB large page mappings for kernel text.
+ */
+#define X64_ALIGN_DEBUG_RODATA_BEGIN . = ALIGN(HPAGE_SIZE);
+
+#define X64_ALIGN_DEBUG_RODATA_END \
+ . = ALIGN(HPAGE_SIZE); \
+ __end_rodata_hpage_align = .;
+
+#else
+
+#define X64_ALIGN_DEBUG_RODATA_BEGIN
+#define X64_ALIGN_DEBUG_RODATA_END
+
+#endif
+
PHDRS {
text PT_LOAD FLAGS(5); /* R_E */
data PT_LOAD FLAGS(7); /* RWE */
#ifdef CONFIG_X86_64
- user PT_LOAD FLAGS(7); /* RWE */
- data.init PT_LOAD FLAGS(7); /* RWE */
+ user PT_LOAD FLAGS(5); /* R_E */
#ifdef CONFIG_SMP
- percpu PT_LOAD FLAGS(7); /* RWE */
+ percpu PT_LOAD FLAGS(6); /* RW_ */
#endif
- data.init2 PT_LOAD FLAGS(7); /* RWE */
+ init PT_LOAD FLAGS(7); /* RWE */
#endif
note PT_NOTE FLAGS(0); /* ___ */
}
@@ -66,17 +91,11 @@ SECTIONS
#endif
/* Text and read-only data */
-
- /* bootstrapping code */
- .text.head : AT(ADDR(.text.head) - LOAD_OFFSET) {
- _text = .;
- *(.text.head)
- } :text = 0x9090
-
- /* The rest of the text */
.text : AT(ADDR(.text) - LOAD_OFFSET) {
+ _text = .;
+ /* bootstrapping code */
+ HEAD_TEXT
#ifdef CONFIG_X86_32
- /* not really needed, already page aligned */
. = ALIGN(PAGE_SIZE);
*(.text.page_aligned)
#endif
@@ -95,93 +114,63 @@ SECTIONS
NOTES :text :note
- /* Exception table */
- . = ALIGN(16);
- __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
- __start___ex_table = .;
- *(__ex_table)
- __stop___ex_table = .;
- } :text = 0x9090
+ EXCEPTION_TABLE(16) :text = 0x9090
- RODATA
+ X64_ALIGN_DEBUG_RODATA_BEGIN
+ RO_DATA(PAGE_SIZE)
+ X64_ALIGN_DEBUG_RODATA_END
/* Data */
- . = ALIGN(PAGE_SIZE);
.data : AT(ADDR(.data) - LOAD_OFFSET) {
/* Start of data section */
_sdata = .;
- DATA_DATA
- CONSTRUCTORS
- } :data
+
+ /* init_task */
+ INIT_TASK_DATA(THREAD_SIZE)
#ifdef CONFIG_X86_32
- /* 32 bit has nosave before _edata */
- . = ALIGN(PAGE_SIZE);
- .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
- __nosave_begin = .;
- *(.data.nosave)
- . = ALIGN(PAGE_SIZE);
- __nosave_end = .;
- }
+ /* 32 bit has nosave before _edata */
+ NOSAVE_DATA
#endif
- . = ALIGN(PAGE_SIZE);
- .data.page_aligned : AT(ADDR(.data.page_aligned) - LOAD_OFFSET) {
- *(.data.page_aligned)
- *(.data.idt)
- }
+ PAGE_ALIGNED_DATA(PAGE_SIZE)
-#ifdef CONFIG_X86_32
- . = ALIGN(32);
-#else
- . = ALIGN(PAGE_SIZE);
- . = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
-#endif
- .data.cacheline_aligned :
- AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET) {
- *(.data.cacheline_aligned)
- }
+ CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES)
- /* rarely changed data like cpu maps */
-#ifdef CONFIG_X86_32
- . = ALIGN(32);
-#else
- . = ALIGN(CONFIG_X86_INTERNODE_CACHE_BYTES);
-#endif
- .data.read_mostly : AT(ADDR(.data.read_mostly) - LOAD_OFFSET) {
- *(.data.read_mostly)
+ DATA_DATA
+ CONSTRUCTORS
+
+ /* rarely changed data like cpu maps */
+ READ_MOSTLY_DATA(INTERNODE_CACHE_BYTES)
/* End of data section */
_edata = .;
- }
+ } :data
#ifdef CONFIG_X86_64
#define VSYSCALL_ADDR (-10*1024*1024)
-#define VSYSCALL_PHYS_ADDR ((LOADADDR(.data.read_mostly) + \
- SIZEOF(.data.read_mostly) + 4095) & ~(4095))
-#define VSYSCALL_VIRT_ADDR ((ADDR(.data.read_mostly) + \
- SIZEOF(.data.read_mostly) + 4095) & ~(4095))
-#define VLOAD_OFFSET (VSYSCALL_ADDR - VSYSCALL_PHYS_ADDR)
+#define VLOAD_OFFSET (VSYSCALL_ADDR - __vsyscall_0 + LOAD_OFFSET)
#define VLOAD(x) (ADDR(x) - VLOAD_OFFSET)
-#define VVIRT_OFFSET (VSYSCALL_ADDR - VSYSCALL_VIRT_ADDR)
+#define VVIRT_OFFSET (VSYSCALL_ADDR - __vsyscall_0)
#define VVIRT(x) (ADDR(x) - VVIRT_OFFSET)
+ . = ALIGN(4096);
+ __vsyscall_0 = .;
+
. = VSYSCALL_ADDR;
- .vsyscall_0 : AT(VSYSCALL_PHYS_ADDR) {
+ .vsyscall_0 : AT(VLOAD(.vsyscall_0)) {
*(.vsyscall_0)
} :user
- __vsyscall_0 = VSYSCALL_VIRT_ADDR;
-
- . = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
+ . = ALIGN(L1_CACHE_BYTES);
.vsyscall_fn : AT(VLOAD(.vsyscall_fn)) {
*(.vsyscall_fn)
}
- . = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
+ . = ALIGN(L1_CACHE_BYTES);
.vsyscall_gtod_data : AT(VLOAD(.vsyscall_gtod_data)) {
*(.vsyscall_gtod_data)
}
@@ -205,7 +194,7 @@ SECTIONS
}
vgetcpu_mode = VVIRT(.vgetcpu_mode);
- . = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
+ . = ALIGN(L1_CACHE_BYTES);
.jiffies : AT(VLOAD(.jiffies)) {
*(.jiffies)
}
@@ -215,11 +204,9 @@ SECTIONS
*(.vsyscall_3)
}
- . = VSYSCALL_VIRT_ADDR + PAGE_SIZE;
+ . = __vsyscall_0 + PAGE_SIZE;
#undef VSYSCALL_ADDR
-#undef VSYSCALL_PHYS_ADDR
-#undef VSYSCALL_VIRT_ADDR
#undef VLOAD_OFFSET
#undef VLOAD
#undef VVIRT_OFFSET
@@ -227,57 +214,27 @@ SECTIONS
#endif /* CONFIG_X86_64 */
- /* init_task */
- . = ALIGN(THREAD_SIZE);
- .data.init_task : AT(ADDR(.data.init_task) - LOAD_OFFSET) {
- *(.data.init_task)
- }
-#ifdef CONFIG_X86_64
- :data.init
-#endif
-
- /*
- * smp_locks might be freed after init
- * start/end must be page aligned
- */
- . = ALIGN(PAGE_SIZE);
- .smp_locks : AT(ADDR(.smp_locks) - LOAD_OFFSET) {
- __smp_locks = .;
- *(.smp_locks)
- __smp_locks_end = .;
- . = ALIGN(PAGE_SIZE);
- }
-
/* Init code and data - will be freed after init */
. = ALIGN(PAGE_SIZE);
- .init.text : AT(ADDR(.init.text) - LOAD_OFFSET) {
+ .init.begin : AT(ADDR(.init.begin) - LOAD_OFFSET) {
__init_begin = .; /* paired with __init_end */
- _sinittext = .;
- INIT_TEXT
- _einittext = .;
}
- .init.data : AT(ADDR(.init.data) - LOAD_OFFSET) {
- INIT_DATA
- }
+#if defined(CONFIG_X86_64) && defined(CONFIG_SMP)
+ /*
+ * percpu offsets are zero-based on SMP. PERCPU_VADDR() changes the
+ * output PHDR, so the next output section - .init.text - should
+ * start another segment - init.
+ */
+ PERCPU_VADDR(0, :percpu)
+#endif
- . = ALIGN(16);
- .init.setup : AT(ADDR(.init.setup) - LOAD_OFFSET) {
- __setup_start = .;
- *(.init.setup)
- __setup_end = .;
- }
- .initcall.init : AT(ADDR(.initcall.init) - LOAD_OFFSET) {
- __initcall_start = .;
- INITCALLS
- __initcall_end = .;
- }
+ INIT_TEXT_SECTION(PAGE_SIZE)
+#ifdef CONFIG_X86_64
+ :init
+#endif
- .con_initcall.init : AT(ADDR(.con_initcall.init) - LOAD_OFFSET) {
- __con_initcall_start = .;
- *(.con_initcall.init)
- __con_initcall_end = .;
- }
+ INIT_DATA_SECTION(16)
.x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) {
__x86_cpu_dev_start = .;
@@ -285,8 +242,6 @@ SECTIONS
__x86_cpu_dev_end = .;
}
- SECURITY_INIT
-
. = ALIGN(8);
.parainstructions : AT(ADDR(.parainstructions) - LOAD_OFFSET) {
__parainstructions = .;
@@ -317,26 +272,7 @@ SECTIONS
EXIT_DATA
}
-#ifdef CONFIG_BLK_DEV_INITRD
- . = ALIGN(PAGE_SIZE);
- .init.ramfs : AT(ADDR(.init.ramfs) - LOAD_OFFSET) {
- __initramfs_start = .;
- *(.init.ramfs)
- __initramfs_end = .;
- }
-#endif
-
-#if defined(CONFIG_X86_64) && defined(CONFIG_SMP)
- /*
- * percpu offsets are zero-based on SMP. PERCPU_VADDR() changes the
- * output PHDR, so the next output section - __data_nosave - should
- * start another section data.init2. Also, pda should be at the head of
- * percpu area. Preallocate it and define the percpu offset symbol
- * so that it can be accessed as a percpu variable.
- */
- . = ALIGN(PAGE_SIZE);
- PERCPU_VADDR(0, :percpu)
-#else
+#if !defined(CONFIG_X86_64) || !defined(CONFIG_SMP)
PERCPU(PAGE_SIZE)
#endif
@@ -347,15 +283,22 @@ SECTIONS
__init_end = .;
}
+ /*
+ * smp_locks might be freed after init
+ * start/end must be page aligned
+ */
+ . = ALIGN(PAGE_SIZE);
+ .smp_locks : AT(ADDR(.smp_locks) - LOAD_OFFSET) {
+ __smp_locks = .;
+ *(.smp_locks)
+ __smp_locks_end = .;
+ . = ALIGN(PAGE_SIZE);
+ }
+
#ifdef CONFIG_X86_64
.data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
- . = ALIGN(PAGE_SIZE);
- __nosave_begin = .;
- *(.data.nosave)
- . = ALIGN(PAGE_SIZE);
- __nosave_end = .;
- } :data.init2
- /* use another section data.init2, see PERCPU_VADDR() above */
+ NOSAVE_DATA
+ }
#endif
/* BSS */
@@ -380,19 +323,19 @@ SECTIONS
_end = .;
}
- /* Sections to be discarded */
- /DISCARD/ : {
- *(.exitcall.exit)
- *(.eh_frame)
- *(.discard)
- }
-
STABS_DEBUG
DWARF_DEBUG
+
+ /* Sections to be discarded */
+ DISCARDS
+ /DISCARD/ : { *(.eh_frame) }
}
#ifdef CONFIG_X86_32
+/*
+ * The ASSERT() sink to . is intentional, for binutils 2.14 compatibility:
+ */
. = ASSERT((_end - LOAD_OFFSET <= KERNEL_IMAGE_SIZE),
"kernel image bigger than KERNEL_IMAGE_SIZE");
#else
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-29 08:57:13 +0000