linux/arch/x86/lib/Makefile
Arvind Sankar aef0148f36 x86/cmdline: Disable jump tables for cmdline.c
When CONFIG_RETPOLINE is disabled, Clang uses a jump table for the
switch statement in cmdline_find_option (jump tables are disabled when
CONFIG_RETPOLINE is enabled). This function is called very early in boot
from sme_enable() if CONFIG_AMD_MEM_ENCRYPT is enabled. At this time,
the kernel is still executing out of the identity mapping, but the jump
table will contain virtual addresses.

Fix this by disabling jump tables for cmdline.c when AMD_MEM_ENCRYPT is
enabled.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200903023056.3914690-1-nivedita@alum.mit.edu
2020-09-03 10:59:16 +02:00

73 lines
2.2 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
#
# Makefile for x86 specific library files.
#
# Produces uninteresting flaky coverage.
KCOV_INSTRUMENT_delay.o := n
# KCSAN uses udelay for introducing watchpoint delay; avoid recursion.
KCSAN_SANITIZE_delay.o := n
ifdef CONFIG_KCSAN
# In case KCSAN+lockdep+ftrace are enabled, disable ftrace for delay.o to avoid
# lockdep -> [other libs] -> KCSAN -> udelay -> ftrace -> lockdep recursion.
CFLAGS_REMOVE_delay.o = $(CC_FLAGS_FTRACE)
endif
# Early boot use of cmdline; don't instrument it
ifdef CONFIG_AMD_MEM_ENCRYPT
KCOV_INSTRUMENT_cmdline.o := n
KASAN_SANITIZE_cmdline.o := n
KCSAN_SANITIZE_cmdline.o := n
ifdef CONFIG_FUNCTION_TRACER
CFLAGS_REMOVE_cmdline.o = -pg
endif
CFLAGS_cmdline.o := -fno-stack-protector -fno-jump-tables
endif
inat_tables_script = $(srctree)/arch/x86/tools/gen-insn-attr-x86.awk
inat_tables_maps = $(srctree)/arch/x86/lib/x86-opcode-map.txt
quiet_cmd_inat_tables = GEN $@
cmd_inat_tables = $(AWK) -f $(inat_tables_script) $(inat_tables_maps) > $@
$(obj)/inat-tables.c: $(inat_tables_script) $(inat_tables_maps)
$(call cmd,inat_tables)
$(obj)/inat.o: $(obj)/inat-tables.c
clean-files := inat-tables.c
obj-$(CONFIG_SMP) += msr-smp.o cache-smp.o
lib-y := delay.o misc.o cmdline.o cpu.o
lib-y += usercopy_$(BITS).o usercopy.o getuser.o putuser.o
lib-y += memcpy_$(BITS).o
lib-$(CONFIG_INSTRUCTION_DECODER) += insn.o inat.o insn-eval.o
lib-$(CONFIG_RANDOMIZE_BASE) += kaslr.o
lib-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o
lib-$(CONFIG_RETPOLINE) += retpoline.o
obj-y += msr.o msr-reg.o msr-reg-export.o hweight.o
obj-y += iomem.o
ifeq ($(CONFIG_X86_32),y)
obj-y += atomic64_32.o
lib-y += atomic64_cx8_32.o
lib-y += checksum_32.o
lib-y += strstr_32.o
lib-y += string_32.o
ifneq ($(CONFIG_X86_CMPXCHG64),y)
lib-y += cmpxchg8b_emu.o atomic64_386_32.o
endif
lib-$(CONFIG_X86_USE_3DNOW) += mmx_32.o
else
obj-y += iomap_copy_64.o
lib-y += csum-partial_64.o csum-copy_64.o csum-wrappers_64.o
lib-y += clear_page_64.o copy_page_64.o
lib-y += memmove_64.o memset_64.o
lib-y += copy_user_64.o
lib-y += cmpxchg16b_emu.o
endif