[PATCH 1/2] ARM: add TEXT_OFFSET to decompressor kexec image structure

Russell King
2020-08-06T11:15:39Z

Add the TEXT_OFFSET to the decompressor's kexec image structure to
kexec knows what offset to use.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
arch/arm/Makefile | 3 +++
arch/arm/boot/compressed/Makefile | 1 +
arch/arm/boot/compressed/vmlinux.lds.S | 3 ++-
3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 01ed27a538b4..ab2d66e40b7f 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -139,6 +139,9 @@ head-y := arch/arm/kernel/head$(MMUEXT).o

# Text offset. This list is sorted numerically by address in order to
# provide a means to avoid/resolve conflicts in multi-arch kernels.
+# Note: the 32kB below this value is reserved for use by the kernel
+# during boot, and this offset is critical to the functioning of
+# kexec-tools.
textofs-y := 0x00008000
# We don't want the htc bootloader to corrupt kernel during resume
textofs-$(CONFIG_PM_H1940) := 0x00108000
diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
index 433fb7f04aa5..0890d82b8cf4 100644
--- a/arch/arm/boot/compressed/Makefile
+++ b/arch/arm/boot/compressed/Makefile
@@ -70,6 +70,7 @@ ZBSSADDR := ALIGN(8)
endif

CPPFLAGS_vmlinux.lds := -DTEXT_START="$(ZTEXTADDR)" -DBSS_START="$(ZBSSADDR)"
+CPPFLAGS_vmlinux.lds += -DTEXT_OFFSET="$(TEXT_OFFSET)"

compress-$(CONFIG_KERNEL_GZIP) = gzip
compress-$(CONFIG_KERNEL_LZO) = lzo
diff --git a/arch/arm/boot/compressed/vmlinux.lds.S b/arch/arm/boot/compressed/vmlinux.lds.S
index 09ac33f52814..da1f6fa5345b 100644
--- a/arch/arm/boot/compressed/vmlinux.lds.S
+++ b/arch/arm/boot/compressed/vmlinux.lds.S
@@ -42,10 +42,11 @@ SECTIONS
}
.table : ALIGN(4) {
_table_start = .;
- LONG(ZIMAGE_MAGIC(4))
+ LONG(ZIMAGE_MAGIC(5))
LONG(ZIMAGE_MAGIC(0x5a534c4b))
LONG(ZIMAGE_MAGIC(__piggy_size_addr - _start))
LONG(ZIMAGE_MAGIC(_kernel_bss_size))
+ LONG(ZIMAGE_MAGIC(TEXT_OFFSET))
LONG(0)
_table_end = .;
}
--
2.20.1