arm64: kernel: Disable latent_entropy GCC plugin in early C runtime

In subsequent patches, mark portions of the early C code will be marked
as __init.  Unfortunarely, __init implies __latent_entropy, and this
would result in the early C code being instrumented in an unsafe manner.

Disable the latent entropy plugin for the early C code.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20231129111555.3594833-44-ardb@google.com
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/arch/arm64/kernel/pi/Makefile b/arch/arm64/kernel/pi/Makefile
index 4c0ea3cd4ea406b63d711c257fc9f04fc8437068..c844a0546d7f0e628610b331fdae2c33ad6fdc6d 100644 (file)
--- a/arch/arm64/kernel/pi/Makefile
+++ b/arch/arm64/kernel/pi/Makefile
@@ -3,6 +3,7 @@
 
 KBUILD_CFLAGS  := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) -fpie \
                   -Os -DDISABLE_BRANCH_PROFILING $(DISABLE_STACKLEAK_PLUGIN) \
+                  $(DISABLE_LATENT_ENTROPY_PLUGIN) \
                   $(call cc-option,-mbranch-protection=none) \
                   -I$(srctree)/scripts/dtc/libfdt -fno-stack-protector \
                   -include $(srctree)/include/linux/hidden.h \