[PATCH] arm64: get rid of TEXT_OFFSET
Ard Biesheuvel
ardb at kernel.org
Tue Aug 25 09:54:40 EDT 2020
TEXT_OFFSET serves no purpose, and for this reason, it was redefined
as 0x0 in the v5.8 timeframe. Since this does not appear to have caused
any issues that require us to revisit that decision, let's get rid of the
macro entirely, along with any references to it.
Signed-off-by: Ard Biesheuvel <ardb at kernel.org>
---
arch/arm64/Makefile | 6 ------
arch/arm64/include/asm/boot.h | 3 +--
arch/arm64/include/asm/kernel-pgtable.h | 2 +-
arch/arm64/include/asm/memory.h | 2 +-
arch/arm64/kernel/Makefile | 2 --
arch/arm64/kernel/head.S | 16 ++++++----------
arch/arm64/kernel/image.h | 1 -
arch/arm64/kernel/vmlinux.lds.S | 4 ++--
drivers/firmware/efi/libstub/Makefile | 1 -
drivers/firmware/efi/libstub/arm64-stub.c | 6 +++---
10 files changed, 14 insertions(+), 29 deletions(-)
diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index 55bc8546d9c7..6d068646da35 100644
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -11,7 +11,6 @@
# Copyright (C) 1995-2001 by Russell King
LDFLAGS_vmlinux :=--no-undefined -X
-CPPFLAGS_vmlinux.lds = -DTEXT_OFFSET=$(TEXT_OFFSET)
ifeq ($(CONFIG_RELOCATABLE), y)
# Pass --no-apply-dynamic-relocs to restore pre-binutils-2.27 behaviour
@@ -127,9 +126,6 @@ endif
# Default value
head-y := arch/arm64/kernel/head.o
-# The byte offset of the kernel image in RAM from the start of RAM.
-TEXT_OFFSET := 0x0
-
ifeq ($(CONFIG_KASAN_SW_TAGS), y)
KASAN_SHADOW_SCALE_SHIFT := 4
else
@@ -140,8 +136,6 @@ KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
-export TEXT_OFFSET
-
core-y += arch/arm64/
libs-y := arch/arm64/lib/ $(libs-y)
libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
diff --git a/arch/arm64/include/asm/boot.h b/arch/arm64/include/asm/boot.h
index c7f67da13cd9..3e7943fd17a4 100644
--- a/arch/arm64/include/asm/boot.h
+++ b/arch/arm64/include/asm/boot.h
@@ -13,8 +13,7 @@
#define MAX_FDT_SIZE SZ_2M
/*
- * arm64 requires the kernel image to placed
- * TEXT_OFFSET bytes beyond a 2 MB aligned base
+ * arm64 requires the kernel image to placed at a 2 MB aligned base address
*/
#define MIN_KIMG_ALIGN SZ_2M
diff --git a/arch/arm64/include/asm/kernel-pgtable.h b/arch/arm64/include/asm/kernel-pgtable.h
index 329fb15f6bac..19ca76ea60d9 100644
--- a/arch/arm64/include/asm/kernel-pgtable.h
+++ b/arch/arm64/include/asm/kernel-pgtable.h
@@ -86,7 +86,7 @@
+ EARLY_PGDS((vstart), (vend)) /* each PGDIR needs a next level page table */ \
+ EARLY_PUDS((vstart), (vend)) /* each PUD needs a next level page table */ \
+ EARLY_PMDS((vstart), (vend))) /* each PMD needs a next level page table */
-#define INIT_DIR_SIZE (PAGE_SIZE * EARLY_PAGES(KIMAGE_VADDR + TEXT_OFFSET, _end))
+#define INIT_DIR_SIZE (PAGE_SIZE * EARLY_PAGES(KIMAGE_VADDR, _end))
#define IDMAP_DIR_SIZE (IDMAP_PGTABLE_LEVELS * PAGE_SIZE)
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
index afa722504bfd..20a9b322d342 100644
--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -169,7 +169,7 @@ extern s64 memstart_addr;
/* PHYS_OFFSET - the physical address of the start of memory. */
#define PHYS_OFFSET ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
-/* the virtual base of the kernel image (minus TEXT_OFFSET) */
+/* the virtual base of the kernel image */
extern u64 kimage_vaddr;
/* the offset between the kernel virtual and physical mappings */
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index a561cbb91d4d..4197ef2fb22e 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -3,8 +3,6 @@
# Makefile for the linux kernel.
#
-CPPFLAGS_vmlinux.lds := -DTEXT_OFFSET=$(TEXT_OFFSET)
-AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
CFLAGS_armv8_deprecated.o := -I$(src)
CFLAGS_REMOVE_ftrace.o = $(CC_FLAGS_FTRACE)
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 037421c66b14..d8d9caf02834 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -36,14 +36,10 @@
#include "efi-header.S"
-#define __PHYS_OFFSET (KERNEL_START - TEXT_OFFSET)
+#define __PHYS_OFFSET KERNEL_START
-#if (TEXT_OFFSET & 0xfff) != 0
-#error TEXT_OFFSET must be at least 4KB aligned
-#elif (PAGE_OFFSET & 0x1fffff) != 0
+#if (PAGE_OFFSET & 0x1fffff) != 0
#error PAGE_OFFSET must be at least 2MB aligned
-#elif TEXT_OFFSET > 0x1fffff
-#error TEXT_OFFSET must be less than 2MB
#endif
/*
@@ -55,7 +51,7 @@
* x0 = physical address to the FDT blob.
*
* This code is mostly position independent so you call this at
- * __pa(PAGE_OFFSET + TEXT_OFFSET).
+ * __pa(PAGE_OFFSET).
*
* Note that the callee-saved registers are used for storing variables
* that are useful before the MMU is enabled. The allocations are described
@@ -77,7 +73,7 @@ _head:
b primary_entry // branch to kernel start, magic
.long 0 // reserved
#endif
- le64sym _kernel_offset_le // Image load offset from start of RAM, little-endian
+ .quad 0 // Image load offset from start of RAM, little-endian
le64sym _kernel_size_le // Effective size of kernel image, little-endian
le64sym _kernel_flags_le // Informative flags, little-endian
.quad 0 // reserved
@@ -382,7 +378,7 @@ SYM_FUNC_START_LOCAL(__create_page_tables)
* Map the kernel image (starting with PHYS_OFFSET).
*/
adrp x0, init_pg_dir
- mov_q x5, KIMAGE_VADDR + TEXT_OFFSET // compile time __va(_text)
+ mov_q x5, KIMAGE_VADDR // compile time __va(_text)
add x5, x5, x23 // add KASLR displacement
mov x4, PTRS_PER_PGD
adrp x6, _end // runtime __pa(_end)
@@ -474,7 +470,7 @@ SYM_FUNC_END(__primary_switched)
.pushsection ".rodata", "a"
SYM_DATA_START(kimage_vaddr)
- .quad _text - TEXT_OFFSET
+ .quad _text
SYM_DATA_END(kimage_vaddr)
EXPORT_SYMBOL(kimage_vaddr)
.popsection
diff --git a/arch/arm64/kernel/image.h b/arch/arm64/kernel/image.h
index c7d38c660372..7bc3ba897901 100644
--- a/arch/arm64/kernel/image.h
+++ b/arch/arm64/kernel/image.h
@@ -62,7 +62,6 @@
*/
#define HEAD_SYMBOLS \
DEFINE_IMAGE_LE64(_kernel_size_le, _end - _text); \
- DEFINE_IMAGE_LE64(_kernel_offset_le, TEXT_OFFSET); \
DEFINE_IMAGE_LE64(_kernel_flags_le, __HEAD_FLAGS);
#endif /* __ARM64_KERNEL_IMAGE_H */
diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index ec8e894684a7..f49bd7f14b19 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -97,7 +97,7 @@ SECTIONS
*(.eh_frame)
}
- . = KIMAGE_VADDR + TEXT_OFFSET;
+ . = KIMAGE_VADDR;
.head.text : {
_text = .;
@@ -266,4 +266,4 @@ ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) == PAGE_SIZE,
/*
* If padding is applied before .head.text, virt<->phys conversions will fail.
*/
-ASSERT(_text == (KIMAGE_VADDR + TEXT_OFFSET), "HEAD is misaligned")
+ASSERT(_text == KIMAGE_VADDR, "HEAD is misaligned")
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index 296b18fbd7a2..5a80cf6bd606 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -64,7 +64,6 @@ lib-$(CONFIG_ARM) += arm32-stub.o
lib-$(CONFIG_ARM64) += arm64-stub.o
lib-$(CONFIG_X86) += x86-stub.o
CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
-CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
#
# For x86, bootloaders like systemd-boot or grub-efi do not zero-initialize the
diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c
index e5bfac79e5ac..fc178398f1ac 100644
--- a/drivers/firmware/efi/libstub/arm64-stub.c
+++ b/drivers/firmware/efi/libstub/arm64-stub.c
@@ -77,7 +77,7 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
kernel_size = _edata - _text;
kernel_memsize = kernel_size + (_end - _edata);
- *reserve_size = kernel_memsize + TEXT_OFFSET % min_kimg_align();
+ *reserve_size = kernel_memsize;
if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && phys_seed != 0) {
/*
@@ -91,7 +91,7 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
}
if (status != EFI_SUCCESS) {
- if (IS_ALIGNED((u64)_text - TEXT_OFFSET, min_kimg_align())) {
+ if (IS_ALIGNED((u64)_text, min_kimg_align())) {
/*
* Just execute from wherever we were loaded by the
* UEFI PE/COFF loader if the alignment is suitable.
@@ -111,7 +111,7 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
}
}
- *image_addr = *reserve_addr + TEXT_OFFSET % min_kimg_align();
+ *image_addr = *reserve_addr;
memcpy((void *)*image_addr, _text, kernel_size);
return EFI_SUCCESS;
--
2.17.1
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