linux/tools/testing/selftests/x86/Makefile
Chang S. Bae 6a3e0651b4 selftests/x86/amx: Add test cases for AMX state management
AMX TILEDATA is a very large XSAVE feature.  It could have caused
nasty XSAVE buffer space waste in two places:

 * Signal stacks
 * Kernel task_struct->fpu buffers

To avoid this waste, neither of these buffers have AMX state by
default.  The non-default features are called "dynamic" features.

There is an arch_prctl(ARCH_REQ_XCOMP_PERM) which allows a task
to declare that it wants to use AMX or other "dynamic" XSAVE
features.  This arch_prctl() ensures that sufficient sigaltstack
space is available before it will succeed.  It also expands the
task_struct buffer.

Functions of this test:
 * Test arch_prctl(ARCH_REQ_XCOMP_PERM).  Ensure that it checks for
   proper sigaltstack sizing and that the sizing is enforced for
   future sigaltstack calls.
 * Ensure that ARCH_REQ_XCOMP_PERM is inherited across fork()
 * Ensure that TILEDATA use before the prctl() is fatal
 * Ensure that TILEDATA is cleared across fork()

Note: Generally, compiler support is needed to do something with
AMX.  Instead, directly load AMX state from userspace with a
plain XSAVE.  Do not depend on the compiler.

 [ dhansen: bunches of cleanups ]

Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211026122524.7BEDAA95@davehans-spike.ostc.intel.com
2021-10-28 14:35:27 +02:00

108 lines
3.4 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
all:
include ../lib.mk
.PHONY: all all_32 all_64 warn_32bit_failure clean
UNAME_M := $(shell uname -m)
CAN_BUILD_I386 := $(shell ./check_cc.sh $(CC) trivial_32bit_program.c -m32)
CAN_BUILD_X86_64 := $(shell ./check_cc.sh $(CC) trivial_64bit_program.c)
CAN_BUILD_WITH_NOPIE := $(shell ./check_cc.sh $(CC) trivial_program.c -no-pie)
TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt test_mremap_vdso \
check_initial_reg_state sigreturn iopl ioperm \
test_vsyscall mov_ss_trap \
syscall_arg_fault fsgsbase_restore sigaltstack
TARGETS_C_32BIT_ONLY := entry_from_vm86 test_syscall_vdso unwind_vdso \
test_FCMOV test_FCOMI test_FISTTP \
vdso_restorer
TARGETS_C_64BIT_ONLY := fsgsbase sysret_rip syscall_numbering \
corrupt_xstate_header amx
# Some selftests require 32bit support enabled also on 64bit systems
TARGETS_C_32BIT_NEEDED := ldt_gdt ptrace_syscall
TARGETS_C_32BIT_ALL := $(TARGETS_C_BOTHBITS) $(TARGETS_C_32BIT_ONLY) $(TARGETS_C_32BIT_NEEDED)
TARGETS_C_64BIT_ALL := $(TARGETS_C_BOTHBITS) $(TARGETS_C_64BIT_ONLY)
ifeq ($(CAN_BUILD_I386)$(CAN_BUILD_X86_64),11)
TARGETS_C_64BIT_ALL += $(TARGETS_C_32BIT_NEEDED)
endif
BINARIES_32 := $(TARGETS_C_32BIT_ALL:%=%_32)
BINARIES_64 := $(TARGETS_C_64BIT_ALL:%=%_64)
BINARIES_32 := $(patsubst %,$(OUTPUT)/%,$(BINARIES_32))
BINARIES_64 := $(patsubst %,$(OUTPUT)/%,$(BINARIES_64))
CFLAGS := -O2 -g -std=gnu99 -pthread -Wall
# call32_from_64 in thunks.S uses absolute addresses.
ifeq ($(CAN_BUILD_WITH_NOPIE),1)
CFLAGS += -no-pie
endif
define gen-target-rule-32
$(1) $(1)_32: $(OUTPUT)/$(1)_32
.PHONY: $(1) $(1)_32
endef
define gen-target-rule-64
$(1) $(1)_64: $(OUTPUT)/$(1)_64
.PHONY: $(1) $(1)_64
endef
ifeq ($(CAN_BUILD_I386),1)
all: all_32
TEST_PROGS += $(BINARIES_32)
EXTRA_CFLAGS += -DCAN_BUILD_32
$(foreach t,$(TARGETS_C_32BIT_ALL),$(eval $(call gen-target-rule-32,$(t))))
endif
ifeq ($(CAN_BUILD_X86_64),1)
all: all_64
TEST_PROGS += $(BINARIES_64)
EXTRA_CFLAGS += -DCAN_BUILD_64
$(foreach t,$(TARGETS_C_64BIT_ALL),$(eval $(call gen-target-rule-64,$(t))))
endif
all_32: $(BINARIES_32)
all_64: $(BINARIES_64)
EXTRA_CLEAN := $(BINARIES_32) $(BINARIES_64)
$(BINARIES_32): $(OUTPUT)/%_32: %.c helpers.h
$(CC) -m32 -o $@ $(CFLAGS) $(EXTRA_CFLAGS) $^ -lrt -ldl -lm
$(BINARIES_64): $(OUTPUT)/%_64: %.c helpers.h
$(CC) -m64 -o $@ $(CFLAGS) $(EXTRA_CFLAGS) $^ -lrt -ldl
# x86_64 users should be encouraged to install 32-bit libraries
ifeq ($(CAN_BUILD_I386)$(CAN_BUILD_X86_64),01)
all: warn_32bit_failure
warn_32bit_failure:
@echo "Warning: you seem to have a broken 32-bit build" 2>&1; \
echo "environment. This will reduce test coverage of 64-bit" 2>&1; \
echo "kernels. If you are using a Debian-like distribution," 2>&1; \
echo "try:"; 2>&1; \
echo ""; \
echo " apt-get install gcc-multilib libc6-i386 libc6-dev-i386"; \
echo ""; \
echo "If you are using a Fedora-like distribution, try:"; \
echo ""; \
echo " yum install glibc-devel.*i686"; \
exit 0;
endif
# Some tests have additional dependencies.
$(OUTPUT)/sysret_ss_attrs_64: thunks.S
$(OUTPUT)/ptrace_syscall_32: raw_syscall_helper_32.S
$(OUTPUT)/test_syscall_vdso_32: thunks_32.S
# check_initial_reg_state is special: it needs a custom entry, and it
# needs to be static so that its interpreter doesn't destroy its initial
# state.
$(OUTPUT)/check_initial_reg_state_32: CFLAGS += -Wl,-ereal_start -static
$(OUTPUT)/check_initial_reg_state_64: CFLAGS += -Wl,-ereal_start -static