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-rw-r--r--arch/arm64/kernel/head.S165
1 files changed, 85 insertions, 80 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 85da0f5..2c6e598 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -25,6 +25,7 @@
#include <linux/irqchip/arm-gic-v3.h>
#include <asm/assembler.h>
+#include <asm/boot.h>
#include <asm/ptrace.h>
#include <asm/asm-offsets.h>
#include <asm/cache.h>
@@ -51,9 +52,6 @@
#error TEXT_OFFSET must be less than 2MB
#endif
-#define KERNEL_START _text
-#define KERNEL_END _end
-
/*
* Kernel startup entry point.
* ---------------------------
@@ -102,8 +100,6 @@ _head:
#endif
#ifdef CONFIG_EFI
- .globl __efistub_stext_offset
- .set __efistub_stext_offset, stext - _head
.align 3
pe_header:
.ascii "PE"
@@ -123,11 +119,11 @@ optional_header:
.short 0x20b // PE32+ format
.byte 0x02 // MajorLinkerVersion
.byte 0x14 // MinorLinkerVersion
- .long _end - stext // SizeOfCode
+ .long _end - efi_header_end // SizeOfCode
.long 0 // SizeOfInitializedData
.long 0 // SizeOfUninitializedData
.long __efistub_entry - _head // AddressOfEntryPoint
- .long __efistub_stext_offset // BaseOfCode
+ .long efi_header_end - _head // BaseOfCode
extra_header_fields:
.quad 0 // ImageBase
@@ -144,7 +140,7 @@ extra_header_fields:
.long _end - _head // SizeOfImage
// Everything before the kernel image is considered part of the header
- .long __efistub_stext_offset // SizeOfHeaders
+ .long efi_header_end - _head // SizeOfHeaders
.long 0 // CheckSum
.short 0xa // Subsystem (EFI application)
.short 0 // DllCharacteristics
@@ -188,10 +184,10 @@ section_table:
.byte 0
.byte 0
.byte 0 // end of 0 padding of section name
- .long _end - stext // VirtualSize
- .long __efistub_stext_offset // VirtualAddress
- .long _edata - stext // SizeOfRawData
- .long __efistub_stext_offset // PointerToRawData
+ .long _end - efi_header_end // VirtualSize
+ .long efi_header_end - _head // VirtualAddress
+ .long _edata - efi_header_end // SizeOfRawData
+ .long efi_header_end - _head // PointerToRawData
.long 0 // PointerToRelocations (0 for executables)
.long 0 // PointerToLineNumbers (0 for executables)
@@ -200,20 +196,23 @@ section_table:
.long 0xe0500020 // Characteristics (section flags)
/*
- * EFI will load stext onwards at the 4k section alignment
+ * EFI will load .text onwards at the 4k section alignment
* described in the PE/COFF header. To ensure that instruction
* sequences using an adrp and a :lo12: immediate will function
- * correctly at this alignment, we must ensure that stext is
+ * correctly at this alignment, we must ensure that .text is
* placed at a 4k boundary in the Image to begin with.
*/
.align 12
+efi_header_end:
#endif
+ __INIT
+
ENTRY(stext)
bl preserve_boot_args
bl el2_setup // Drop to EL1, w20=cpu_boot_mode
- mov x23, xzr // KASLR offset, defaults to 0
adrp x24, __PHYS_OFFSET
+ and x23, x24, MIN_KIMG_ALIGN - 1 // KASLR offset, defaults to 0
bl set_cpu_boot_mode_flag
bl __create_page_tables // x25=TTBR0, x26=TTBR1
/*
@@ -222,13 +221,11 @@ ENTRY(stext)
* On return, the CPU will be ready for the MMU to be turned on and
* the TCR will have been set.
*/
- ldr x27, 0f // address to jump to after
+ bl __cpu_setup // initialise processor
+ adr_l x27, __primary_switch // address to jump to after
// MMU has been enabled
- adr_l lr, __enable_mmu // return (PIC) address
- b __cpu_setup // initialise processor
+ b __enable_mmu
ENDPROC(stext)
- .align 3
-0: .quad __mmap_switched - (_head - TEXT_OFFSET) + KIMAGE_VADDR
/*
* Preserve the arguments passed by the bootloader in x0 .. x3
@@ -338,7 +335,7 @@ __create_page_tables:
cmp x0, x6
b.lo 1b
- ldr x7, =SWAPPER_MM_MMUFLAGS
+ mov x7, SWAPPER_MM_MMUFLAGS
/*
* Create the identity mapping.
@@ -394,12 +391,13 @@ __create_page_tables:
* Map the kernel image (starting with PHYS_OFFSET).
*/
mov x0, x26 // swapper_pg_dir
- ldr x5, =KIMAGE_VADDR
+ mov_q x5, KIMAGE_VADDR + TEXT_OFFSET // compile time __va(_text)
add x5, x5, x23 // add KASLR displacement
create_pgd_entry x0, x5, x3, x6
- ldr w6, kernel_img_size
- add x6, x6, x5
- mov x3, x24 // phys offset
+ adrp x6, _end // runtime __pa(_end)
+ adrp x3, _text // runtime __pa(_text)
+ sub x6, x6, x3 // _end - _text
+ add x6, x6, x5 // runtime __va(_end)
create_block_map x0, x7, x3, x5, x6
/*
@@ -414,16 +412,13 @@ __create_page_tables:
ret x28
ENDPROC(__create_page_tables)
-
-kernel_img_size:
- .long _end - (_head - TEXT_OFFSET)
.ltorg
/*
* The following fragment of code is executed with the MMU enabled.
*/
.set initial_sp, init_thread_union + THREAD_START_SP
-__mmap_switched:
+__primary_switched:
mov x28, lr // preserve LR
adr_l x8, vectors // load VBAR_EL1 with virtual
msr vbar_el1, x8 // vector table address
@@ -437,44 +432,6 @@ __mmap_switched:
bl __pi_memset
dsb ishst // Make zero page visible to PTW
-#ifdef CONFIG_RELOCATABLE
-
- /*
- * Iterate over each entry in the relocation table, and apply the
- * relocations in place.
- */
- adr_l x8, __dynsym_start // start of symbol table
- adr_l x9, __reloc_start // start of reloc table
- adr_l x10, __reloc_end // end of reloc table
-
-0: cmp x9, x10
- b.hs 2f
- ldp x11, x12, [x9], #24
- ldr x13, [x9, #-8]
- cmp w12, #R_AARCH64_RELATIVE
- b.ne 1f
- add x13, x13, x23 // relocate
- str x13, [x11, x23]
- b 0b
-
-1: cmp w12, #R_AARCH64_ABS64
- b.ne 0b
- add x12, x12, x12, lsl #1 // symtab offset: 24x top word
- add x12, x8, x12, lsr #(32 - 3) // ... shifted into bottom word
- ldrsh w14, [x12, #6] // Elf64_Sym::st_shndx
- ldr x15, [x12, #8] // Elf64_Sym::st_value
- cmp w14, #-0xf // SHN_ABS (0xfff1) ?
- add x14, x15, x23 // relocate
- csel x15, x14, x15, ne
- add x15, x13, x15
- str x15, [x11, x23]
- b 0b
-
-2: adr_l x8, kimage_vaddr // make relocated kimage_vaddr
- dc cvac, x8 // value visible to secondaries
- dsb sy // with MMU off
-#endif
-
adr_l sp, initial_sp, x4
mov x4, sp
and x4, x4, #~(THREAD_SIZE - 1)
@@ -490,17 +447,19 @@ __mmap_switched:
bl kasan_early_init
#endif
#ifdef CONFIG_RANDOMIZE_BASE
- cbnz x23, 0f // already running randomized?
+ tst x23, ~(MIN_KIMG_ALIGN - 1) // already running randomized?
+ b.ne 0f
mov x0, x21 // pass FDT address in x0
+ mov x1, x23 // pass modulo offset in x1
bl kaslr_early_init // parse FDT for KASLR options
cbz x0, 0f // KASLR disabled? just proceed
- mov x23, x0 // record KASLR offset
+ orr x23, x23, x0 // record KASLR offset
ret x28 // we must enable KASLR, return
// to __enable_mmu()
0:
#endif
b start_kernel
-ENDPROC(__mmap_switched)
+ENDPROC(__primary_switched)
/*
* end early head section, begin head code that is also used for
@@ -650,7 +609,7 @@ ENDPROC(el2_setup)
* Sets the __boot_cpu_mode flag depending on the CPU boot mode passed
* in x20. See arch/arm64/include/asm/virt.h for more info.
*/
-ENTRY(set_cpu_boot_mode_flag)
+set_cpu_boot_mode_flag:
adr_l x1, __boot_cpu_mode
cmp w20, #BOOT_CPU_MODE_EL2
b.ne 1f
@@ -683,7 +642,7 @@ ENTRY(secondary_holding_pen)
bl el2_setup // Drop to EL1, w20=cpu_boot_mode
bl set_cpu_boot_mode_flag
mrs x0, mpidr_el1
- ldr x1, =MPIDR_HWID_BITMASK
+ mov_q x1, MPIDR_HWID_BITMASK
and x0, x0, x1
adr_l x3, secondary_holding_pen_release
pen: ldr x4, [x3]
@@ -703,7 +662,7 @@ ENTRY(secondary_entry)
b secondary_startup
ENDPROC(secondary_entry)
-ENTRY(secondary_startup)
+secondary_startup:
/*
* Common entry point for secondary CPUs.
*/
@@ -711,14 +670,11 @@ ENTRY(secondary_startup)
adrp x26, swapper_pg_dir
bl __cpu_setup // initialise processor
- ldr x8, kimage_vaddr
- ldr w9, 0f
- sub x27, x8, w9, sxtw // address to jump to after enabling the MMU
+ adr_l x27, __secondary_switch // address to jump to after enabling the MMU
b __enable_mmu
ENDPROC(secondary_startup)
-0: .long (_text - TEXT_OFFSET) - __secondary_switched
-ENTRY(__secondary_switched)
+__secondary_switched:
adr_l x5, vectors
msr vbar_el1, x5
isb
@@ -768,7 +724,7 @@ ENTRY(__early_cpu_boot_status)
* If it isn't, park the CPU
*/
.section ".idmap.text", "ax"
-__enable_mmu:
+ENTRY(__enable_mmu)
mrs x22, sctlr_el1 // preserve old SCTLR_EL1 value
mrs x1, ID_AA64MMFR0_EL1
ubfx x2, x1, #ID_AA64MMFR0_TGRAN_SHIFT, 4
@@ -806,7 +762,6 @@ __enable_mmu:
ic iallu // flush instructions fetched
dsb nsh // via old mapping
isb
- add x27, x27, x23 // relocated __mmap_switched
#endif
br x27
ENDPROC(__enable_mmu)
@@ -819,3 +774,53 @@ __no_granule_support:
wfi
b 1b
ENDPROC(__no_granule_support)
+
+__primary_switch:
+#ifdef CONFIG_RELOCATABLE
+ /*
+ * Iterate over each entry in the relocation table, and apply the
+ * relocations in place.
+ */
+ ldr w8, =__dynsym_offset // offset to symbol table
+ ldr w9, =__rela_offset // offset to reloc table
+ ldr w10, =__rela_size // size of reloc table
+
+ mov_q x11, KIMAGE_VADDR // default virtual offset
+ add x11, x11, x23 // actual virtual offset
+ add x8, x8, x11 // __va(.dynsym)
+ add x9, x9, x11 // __va(.rela)
+ add x10, x9, x10 // __va(.rela) + sizeof(.rela)
+
+0: cmp x9, x10
+ b.hs 2f
+ ldp x11, x12, [x9], #24
+ ldr x13, [x9, #-8]
+ cmp w12, #R_AARCH64_RELATIVE
+ b.ne 1f
+ add x13, x13, x23 // relocate
+ str x13, [x11, x23]
+ b 0b
+
+1: cmp w12, #R_AARCH64_ABS64
+ b.ne 0b
+ add x12, x12, x12, lsl #1 // symtab offset: 24x top word
+ add x12, x8, x12, lsr #(32 - 3) // ... shifted into bottom word
+ ldrsh w14, [x12, #6] // Elf64_Sym::st_shndx
+ ldr x15, [x12, #8] // Elf64_Sym::st_value
+ cmp w14, #-0xf // SHN_ABS (0xfff1) ?
+ add x14, x15, x23 // relocate
+ csel x15, x14, x15, ne
+ add x15, x13, x15
+ str x15, [x11, x23]
+ b 0b
+
+2:
+#endif
+ ldr x8, =__primary_switched
+ br x8
+ENDPROC(__primary_switch)
+
+__secondary_switch:
+ ldr x8, =__secondary_switched
+ br x8
+ENDPROC(__secondary_switch)
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