linux/arch/powerpc/lib/Makefile
Daniel Axtens 5352090a99 powerpc/kasan: Don't instrument non-maskable or raw interrupts
Disable address sanitization for raw and non-maskable interrupt
handlers, because they can run in real mode, where we cannot access
the shadow memory.  (Note that kasan_arch_is_ready() doesn't test for
real mode, since it is a static branch for speed, and in any case not
all the entry points to the generic KASAN code are protected by
kasan_arch_is_ready guards.)

The changes to interrupt_nmi_enter/exit_prepare() look larger than
they actually are.  The changes are equivalent to adding
!IS_ENABLED(CONFIG_KASAN) to the conditions for calling nmi_enter() or
nmi_exit() in real mode.  That is, the code is equivalent to using the
following condition for calling nmi_enter/exit:

	if (((!IS_ENABLED(CONFIG_PPC_BOOK3S_64) ||
			!firmware_has_feature(FW_FEATURE_LPAR) ||
			radix_enabled()) &&
		    !IS_ENABLED(CONFIG_KASAN) ||
		(mfmsr() & MSR_DR))

That unwieldy condition has been split into several statements with
comments, for easier reading.

The nmi_ipi_lock functions that call atomic functions (i.e.,
nmi_ipi_lock_start(), nmi_ipi_lock() and nmi_ipi_unlock()), besides
being marked noinstr, now call arch_atomic_* functions instead of
atomic_* functions because with KASAN enabled, the atomic_* functions
are wrappers which explicitly do address sanitization on their
arguments.  Since we are trying to avoid address sanitization, we have
to use the lower-level arch_atomic_* versions.

In hv_nmi_check_nonrecoverable(), the regs_set_unrecoverable() call
has been open-coded so as to avoid having to either trust the inlining
or mark regs_set_unrecoverable() as noinstr.

[paulus@ozlabs.org: combined a few work-in-progress commits of
 Daniel's and wrote the commit message.]

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/YoTFGaKM8Pd46PIK@cleo
2022-05-22 15:58:29 +10:00

80 lines
2.3 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
#
# Makefile for ppc-specific library files..
#
ccflags-$(CONFIG_PPC64) := $(NO_MINIMAL_TOC)
CFLAGS_code-patching.o += -fno-stack-protector
CFLAGS_feature-fixups.o += -fno-stack-protector
CFLAGS_REMOVE_code-patching.o = $(CC_FLAGS_FTRACE)
CFLAGS_REMOVE_feature-fixups.o = $(CC_FLAGS_FTRACE)
KASAN_SANITIZE_code-patching.o := n
KASAN_SANITIZE_feature-fixups.o := n
# restart_table.o contains functions called in the NMI interrupt path
# which can be in real mode. Disable KASAN.
KASAN_SANITIZE_restart_table.o := n
ifdef CONFIG_KASAN
CFLAGS_code-patching.o += -DDISABLE_BRANCH_PROFILING
CFLAGS_feature-fixups.o += -DDISABLE_BRANCH_PROFILING
endif
CFLAGS_code-patching.o += $(DISABLE_LATENT_ENTROPY_PLUGIN)
CFLAGS_feature-fixups.o += $(DISABLE_LATENT_ENTROPY_PLUGIN)
obj-y += alloc.o code-patching.o feature-fixups.o pmem.o
obj-$(CONFIG_CODE_PATCHING_SELFTEST) += test-code-patching.o
ifndef CONFIG_KASAN
obj-y += string.o memcmp_$(BITS).o
obj-$(CONFIG_PPC32) += strlen_32.o
endif
obj-$(CONFIG_PPC32) += div64.o copy_32.o crtsavres.o
obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o
# See corresponding test in arch/powerpc/Makefile
# 64-bit linker creates .sfpr on demand for final link (vmlinux),
# so it is only needed for modules, and only for older linkers which
# do not support --save-restore-funcs
ifeq ($(call ld-ifversion, -lt, 22500, y),y)
extra-$(CONFIG_PPC64) += crtsavres.o
endif
obj-$(CONFIG_PPC_BOOK3S_64) += copyuser_power7.o copypage_power7.o \
memcpy_power7.o restart_table.o
obj64-y += copypage_64.o copyuser_64.o mem_64.o hweight_64.o \
memcpy_64.o copy_mc_64.o
ifndef CONFIG_PPC_QUEUED_SPINLOCKS
obj64-$(CONFIG_SMP) += locks.o
endif
obj64-$(CONFIG_ALTIVEC) += vmx-helper.o
obj64-$(CONFIG_KPROBES_SANITY_TEST) += test_emulate_step.o \
test_emulate_step_exec_instr.o
obj-y += checksum_$(BITS).o checksum_wrappers.o \
string_$(BITS).o
obj-y += sstep.o
obj-$(CONFIG_PPC_FPU) += ldstfp.o
obj64-y += quad.o
obj-$(CONFIG_PPC_LIB_RHEAP) += rheap.o
obj-$(CONFIG_FTR_FIXUP_SELFTEST) += feature-fixups-test.o
obj-$(CONFIG_ALTIVEC) += xor_vmx.o xor_vmx_glue.o
CFLAGS_xor_vmx.o += -maltivec $(call cc-option,-mabi=altivec)
# Enable <altivec.h>
CFLAGS_xor_vmx.o += -isystem $(shell $(CC) -print-file-name=include)
obj-$(CONFIG_PPC64) += $(obj64-y)