@@ -350,6 +350,9 @@ config KASAN_SHADOW_OFFSET
default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
default 0xffffffffffffffff
+config UNWIND_TABLES
+ bool
+
source "arch/arm64/Kconfig.platforms"
menu "Kernel Features"
@@ -10,7 +10,7 @@
#
# Copyright (C) 1995-2001 by Russell King
-LDFLAGS_vmlinux :=--no-undefined -X
+LDFLAGS_vmlinux :=--no-undefined -X --eh-frame-hdr
ifeq ($(CONFIG_RELOCATABLE), y)
# Pass --no-apply-dynamic-relocs to restore pre-binutils-2.27 behaviour
@@ -45,8 +45,13 @@ KBUILD_CFLAGS += $(call cc-option,-mabi=lp64)
KBUILD_AFLAGS += $(call cc-option,-mabi=lp64)
# Avoid generating .eh_frame* sections.
+ifneq ($(CONFIG_UNWIND_TABLES),y)
KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables
KBUILD_AFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables
+else
+KBUILD_CFLAGS += -fasynchronous-unwind-tables
+KBUILD_AFLAGS += -fasynchronous-unwind-tables
+endif
ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y)
prepare: stack_protector_prepare
@@ -111,6 +111,21 @@ jiffies = jiffies_64;
#define TRAMP_TEXT
#endif
+#ifdef CONFIG_UNWIND_TABLES
+#define UNWIND_DATA_SECTIONS \
+ .eh_frame_hdr : { \
+ __eh_frame_hdr = .; \
+ *(.eh_frame_hdr) \
+ } \
+ .eh_frame : { \
+ __eh_frame_start = .; \
+ *(.eh_frame) \
+ __eh_frame_end = .; \
+ }
+#else
+#define UNWIND_DATA_SECTIONS
+#endif
+
/*
* The size of the PE/COFF section that covers the kernel image, which
* runs from _stext to _edata, must be a round multiple of the PE/COFF
@@ -139,6 +154,9 @@ SECTIONS
/DISCARD/ : {
*(.interp .dynamic)
*(.dynsym .dynstr .hash .gnu.hash)
+#ifndef CONFIG_UNWIND_TABLES
+ *(.eh_frame_hdr .eh_frame)
+#endif
}
. = KIMAGE_VADDR;
@@ -217,6 +235,8 @@ SECTIONS
__alt_instructions_end = .;
}
+ UNWIND_DATA_SECTIONS
+
. = ALIGN(SEGMENT_ALIGN);
__inittext_end = .;
__initdata_begin = .;
@@ -20,6 +20,7 @@ cflags-$(CONFIG_X86) += -m$(BITS) -D__KERNEL__ \
# disable the stackleak plugin
cflags-$(CONFIG_ARM64) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
-fpie $(DISABLE_STACKLEAK_PLUGIN) \
+ -fno-unwind-tables -fno-asynchronous-unwind-tables \
$(call cc-option,-mbranch-protection=none)
cflags-$(CONFIG_ARM) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
-fno-builtin -fpic \
Signed-off-by: Ard Biesheuvel <ardb@kernel.org> --- arch/arm64/Kconfig | 3 +++ arch/arm64/Makefile | 7 ++++++- arch/arm64/kernel/vmlinux.lds.S | 20 ++++++++++++++++++++ drivers/firmware/efi/libstub/Makefile | 1 + 4 files changed, 30 insertions(+), 1 deletion(-)