linux/arch/s390/purgatory/Makefile
Philipp Rudo d8de756573 s390/purgatory: Fix endless interrupt loop
New compilers use the floating-point registers as spill registers when
there is high register pressure. In the purgatory however, the afp control
bit is not set. This leads to an exception whenever a floating-point
instruction is used, which again causes an interrupt loop.

Forbid the compiler to use floating-point instructions by adding
-msoft-float to KBUILD_CFLAGS.

Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Fixes: 840798a1f5 (s390/kexec_file: Add purgatory)
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-05-18 07:24:35 +02:00

38 lines
1.2 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
OBJECT_FILES_NON_STANDARD := y
purgatory-y := head.o purgatory.o string.o sha256.o mem.o
targets += $(purgatory-y) purgatory.ro kexec-purgatory.c
PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
$(obj)/sha256.o: $(srctree)/lib/sha256.c
$(call if_changed_rule,cc_o_c)
$(obj)/mem.o: $(srctree)/arch/s390/lib/mem.S
$(call if_changed_rule,as_o_S)
$(obj)/string.o: $(srctree)/arch/s390/lib/string.c
$(call if_changed_rule,cc_o_c)
LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined -nostdlib
LDFLAGS_purgatory.ro += -z nodefaultlib
KBUILD_CFLAGS := -fno-strict-aliasing -Wall -Wstrict-prototypes
KBUILD_CFLAGS += -Wno-pointer-sign -Wno-sign-compare
KBUILD_CFLAGS += -fno-zero-initialized-in-bss -fno-builtin -ffreestanding
KBUILD_CFLAGS += -c -MD -Os -m64 -msoft-float
KBUILD_CFLAGS += $(call cc-option,-fno-PIE)
$(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE
$(call if_changed,ld)
CMD_BIN2C = $(objtree)/scripts/basic/bin2c
quiet_cmd_bin2c = BIN2C $@
cmd_bin2c = $(CMD_BIN2C) kexec_purgatory < $< > $@
$(obj)/kexec-purgatory.c: $(obj)/purgatory.ro FORCE
$(call if_changed,bin2c)
obj-$(CONFIG_ARCH_HAS_KEXEC_PURGATORY) += kexec-purgatory.o