linux/arch/powerpc/Makefile

457 lines
15 KiB
Makefile
Raw Normal View History

# This file is included by the global makefile so that you can add your own
# architecture-specific flags and dependencies.
#
# This file is subject to the terms and conditions of the GNU General Public
# License. See the file "COPYING" in the main directory of this archive
# for more details.
#
# Copyright (C) 1994 by Linus Torvalds
# Changes for PPC by Gary Thomas
# Rewritten by Cort Dougan and Paul Mackerras
#
HAS_BIARCH := $(call cc-option-yn, -m32)
# Set default 32 bits cross compilers for vdso and boot wrapper
CROSS32_COMPILE ?=
ifeq ($(HAS_BIARCH),y)
ifeq ($(CROSS32_COMPILE),)
ifdef CONFIG_PPC32
# These options will be overridden by any -mcpu option that the CPU
# or platform code sets later on the command line, but they are needed
# to set a sane 32-bit cpu target for the 64-bit cross compiler which
# may default to the wrong ISA.
KBUILD_CFLAGS += -mcpu=powerpc
KBUILD_AFLAGS += -mcpu=powerpc
endif
endif
endif
ifdef CONFIG_PPC_BOOK3S_32
KBUILD_CFLAGS += -mcpu=powerpc
endif
# If we're on a ppc/ppc64/ppc64le machine use that defconfig, otherwise just use
# ppc64_defconfig because we have nothing better to go on.
uname := $(shell uname -m)
KBUILD_DEFCONFIG := $(if $(filter ppc%,$(uname)),$(uname),ppc64)_defconfig
new_nm := $(shell if $(NM) --help 2>&1 | grep -- '--synthetic' > /dev/null; then echo y; else echo n; fi)
ifeq ($(new_nm),y)
NM := $(NM) --synthetic
endif
# BITS is used as extension for files which are available in a 32 bit
# and a 64 bit version to simplify shared Makefiles.
# e.g.: obj-y += foo_$(BITS).o
export BITS
ifdef CONFIG_PPC64
BITS := 64
else
BITS := 32
endif
machine-y = ppc
machine-$(CONFIG_PPC64) += 64
machine-$(CONFIG_CPU_LITTLE_ENDIAN) += le
UTS_MACHINE := $(subst $(space),,$(machine-y))
# XXX This needs to be before we override LD below
ifdef CONFIG_PPC32
KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
else
ifeq ($(call ld-ifversion, -ge, 22500, y),y)
# Have the linker provide sfpr if possible.
# There is a corresponding test in arch/powerpc/lib/Makefile
KBUILD_LDFLAGS_MODULE += --save-restore-funcs
else
KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
endif
endif
ifdef CONFIG_CPU_LITTLE_ENDIAN
KBUILD_CFLAGS += -mlittle-endian
KBUILD_LDFLAGS += -EL
LDEMULATION := lppc
GNUTARGET := powerpcle
MULTIPLEWORD := -mno-multiple
KBUILD_CFLAGS_MODULE += $(call cc-option,-mno-save-toc-indirect)
else
KBUILD_CFLAGS += $(call cc-option,-mbig-endian)
KBUILD_LDFLAGS += -EB
LDEMULATION := ppc
GNUTARGET := powerpc
MULTIPLEWORD := -mmultiple
endif
ifdef CONFIG_PPC64
powerpc: Don't add -mabi= flags when building with Clang When building pseries_defconfig, building vdso32 errors out: error: unknown target ABI 'elfv1' This happens because -m32 in clang changes the target to 32-bit, which does not allow the ABI to be changed. Commit 4dc831aa8813 ("powerpc: Fix compiling a BE kernel with a powerpc64le toolchain") added these flags to fix building big endian kernels with a little endian GCC. Clang doesn't need -mabi because the target triple controls the default value. -mlittle-endian and -mbig-endian manipulate the triple into either powerpc64-* or powerpc64le-*, which properly sets the default ABI. Adding a debug print out in the PPC64TargetInfo constructor after line 383 above shows this: $ echo | ./clang -E --target=powerpc64-linux -mbig-endian -o /dev/null - Default ABI: elfv1 $ echo | ./clang -E --target=powerpc64-linux -mlittle-endian -o /dev/null - Default ABI: elfv2 $ echo | ./clang -E --target=powerpc64le-linux -mbig-endian -o /dev/null - Default ABI: elfv1 $ echo | ./clang -E --target=powerpc64le-linux -mlittle-endian -o /dev/null - Default ABI: elfv2 Don't specify -mabi when building with clang to avoid the build error with -m32 and not change any code generation. -mcall-aixdesc is not an implemented flag in clang so it can be safely excluded as well, see commit 238abecde8ad ("powerpc: Don't use gcc specific options on clang"). pseries_defconfig successfully builds after this patch and powernv_defconfig and ppc44x_defconfig don't regress. Reviewed-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> [mpe: Trim clang links in change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191119045712.39633-2-natechancellor@gmail.com
2019-11-19 12:57:10 +08:00
ifndef CONFIG_CC_IS_CLANG
cflags-$(CONFIG_PPC64_ELF_ABI_V1) += $(call cc-option,-mabi=elfv1)
cflags-$(CONFIG_PPC64_ELF_ABI_V1) += $(call cc-option,-mcall-aixdesc)
aflags-$(CONFIG_PPC64_ELF_ABI_V1) += $(call cc-option,-mabi=elfv1)
aflags-$(CONFIG_PPC64_ELF_ABI_V2) += -mabi=elfv2
endif
powerpc: Don't add -mabi= flags when building with Clang When building pseries_defconfig, building vdso32 errors out: error: unknown target ABI 'elfv1' This happens because -m32 in clang changes the target to 32-bit, which does not allow the ABI to be changed. Commit 4dc831aa8813 ("powerpc: Fix compiling a BE kernel with a powerpc64le toolchain") added these flags to fix building big endian kernels with a little endian GCC. Clang doesn't need -mabi because the target triple controls the default value. -mlittle-endian and -mbig-endian manipulate the triple into either powerpc64-* or powerpc64le-*, which properly sets the default ABI. Adding a debug print out in the PPC64TargetInfo constructor after line 383 above shows this: $ echo | ./clang -E --target=powerpc64-linux -mbig-endian -o /dev/null - Default ABI: elfv1 $ echo | ./clang -E --target=powerpc64-linux -mlittle-endian -o /dev/null - Default ABI: elfv2 $ echo | ./clang -E --target=powerpc64le-linux -mbig-endian -o /dev/null - Default ABI: elfv1 $ echo | ./clang -E --target=powerpc64le-linux -mlittle-endian -o /dev/null - Default ABI: elfv2 Don't specify -mabi when building with clang to avoid the build error with -m32 and not change any code generation. -mcall-aixdesc is not an implemented flag in clang so it can be safely excluded as well, see commit 238abecde8ad ("powerpc: Don't use gcc specific options on clang"). pseries_defconfig successfully builds after this patch and powernv_defconfig and ppc44x_defconfig don't regress. Reviewed-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> [mpe: Trim clang links in change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191119045712.39633-2-natechancellor@gmail.com
2019-11-19 12:57:10 +08:00
endif
ifndef CONFIG_CC_IS_CLANG
cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mno-strict-align
endif
cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mbig-endian)
cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mlittle-endian
aflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mbig-endian)
aflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mlittle-endian
ifeq ($(HAS_BIARCH),y)
KBUILD_CFLAGS += -m$(BITS)
KBUILD_AFLAGS += -m$(BITS) -Wl,-a$(BITS)
KBUILD_LDFLAGS += -m elf$(BITS)$(LDEMULATION)
endif
powerpc/32: add stack protector support This functionality was tentatively added in the past (commit 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support")) but had to be reverted (commit f2574030b0e3 ("powerpc: Revert the initial stack protector support") because of GCC implementing it differently whether it had been built with libc support or not. Now, GCC offers the possibility to manually set the stack-protector mode (global or tls) regardless of libc support. This time, the patch selects HAVE_STACKPROTECTOR only if -mstack-protector-guard=tls is supported by GCC. On PPC32, as register r2 points to current task_struct at all time, the stack_canary located inside task_struct can be used directly by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=offsetof(struct task_struct, stack_canary)) The protector is disabled for prom_init and bootx_init as it is too early to handle it properly. $ echo CORRUPT_STACK > /sys/kernel/debug/provoke-crash/DIRECT [ 134.943666] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: lkdtm_CORRUPT_STACK+0x64/0x64 [ 134.943666] [ 134.955414] CPU: 0 PID: 283 Comm: sh Not tainted 4.18.0-s3k-dev-12143-ga3272be41209 #835 [ 134.963380] Call Trace: [ 134.965860] [c6615d60] [c001f76c] panic+0x118/0x260 (unreliable) [ 134.971775] [c6615dc0] [c001f654] panic+0x0/0x260 [ 134.976435] [c6615dd0] [c032c368] lkdtm_CORRUPT_STACK_STRONG+0x0/0x64 [ 134.982769] [c6615e00] [ffffffff] 0xffffffff Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-27 15:05:53 +08:00
cflags-$(CONFIG_STACKPROTECTOR) += -mstack-protector-guard=tls
ifdef CONFIG_PPC64
cflags-$(CONFIG_STACKPROTECTOR) += -mstack-protector-guard-reg=r13
else
powerpc/32: add stack protector support This functionality was tentatively added in the past (commit 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support")) but had to be reverted (commit f2574030b0e3 ("powerpc: Revert the initial stack protector support") because of GCC implementing it differently whether it had been built with libc support or not. Now, GCC offers the possibility to manually set the stack-protector mode (global or tls) regardless of libc support. This time, the patch selects HAVE_STACKPROTECTOR only if -mstack-protector-guard=tls is supported by GCC. On PPC32, as register r2 points to current task_struct at all time, the stack_canary located inside task_struct can be used directly by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=offsetof(struct task_struct, stack_canary)) The protector is disabled for prom_init and bootx_init as it is too early to handle it properly. $ echo CORRUPT_STACK > /sys/kernel/debug/provoke-crash/DIRECT [ 134.943666] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: lkdtm_CORRUPT_STACK+0x64/0x64 [ 134.943666] [ 134.955414] CPU: 0 PID: 283 Comm: sh Not tainted 4.18.0-s3k-dev-12143-ga3272be41209 #835 [ 134.963380] Call Trace: [ 134.965860] [c6615d60] [c001f76c] panic+0x118/0x260 (unreliable) [ 134.971775] [c6615dc0] [c001f654] panic+0x0/0x260 [ 134.976435] [c6615dd0] [c032c368] lkdtm_CORRUPT_STACK_STRONG+0x0/0x64 [ 134.982769] [c6615e00] [ffffffff] 0xffffffff Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-27 15:05:53 +08:00
cflags-$(CONFIG_STACKPROTECTOR) += -mstack-protector-guard-reg=r2
endif
powerpc/32: add stack protector support This functionality was tentatively added in the past (commit 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support")) but had to be reverted (commit f2574030b0e3 ("powerpc: Revert the initial stack protector support") because of GCC implementing it differently whether it had been built with libc support or not. Now, GCC offers the possibility to manually set the stack-protector mode (global or tls) regardless of libc support. This time, the patch selects HAVE_STACKPROTECTOR only if -mstack-protector-guard=tls is supported by GCC. On PPC32, as register r2 points to current task_struct at all time, the stack_canary located inside task_struct can be used directly by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=offsetof(struct task_struct, stack_canary)) The protector is disabled for prom_init and bootx_init as it is too early to handle it properly. $ echo CORRUPT_STACK > /sys/kernel/debug/provoke-crash/DIRECT [ 134.943666] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: lkdtm_CORRUPT_STACK+0x64/0x64 [ 134.943666] [ 134.955414] CPU: 0 PID: 283 Comm: sh Not tainted 4.18.0-s3k-dev-12143-ga3272be41209 #835 [ 134.963380] Call Trace: [ 134.965860] [c6615d60] [c001f76c] panic+0x118/0x260 (unreliable) [ 134.971775] [c6615dc0] [c001f654] panic+0x0/0x260 [ 134.976435] [c6615dd0] [c032c368] lkdtm_CORRUPT_STACK_STRONG+0x0/0x64 [ 134.982769] [c6615e00] [ffffffff] 0xffffffff Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-27 15:05:53 +08:00
LDFLAGS_vmlinux-y := -Bstatic
LDFLAGS_vmlinux-$(CONFIG_RELOCATABLE) := -pie
LDFLAGS_vmlinux-$(CONFIG_RELOCATABLE) += -z notext
LDFLAGS_vmlinux := $(LDFLAGS_vmlinux-y)
ifdef CONFIG_PPC64
ifeq ($(call cc-option-yn,-mcmodel=medium),y)
# -mcmodel=medium breaks modules because it uses 32bit offsets from
# the TOC pointer to create pointers where possible. Pointers into the
# percpu data area are created by this method.
#
# The kernel module loader relocates the percpu data section from the
# original location (starting with 0xd...) to somewhere in the base
# kernel percpu data space (starting with 0xc...). We need a full
# 64bit relocation for this to work, hence -mcmodel=large.
KBUILD_CFLAGS_MODULE += -mcmodel=large
else
export NO_MINIMAL_TOC := -mno-minimal-toc
endif
endif
CFLAGS-$(CONFIG_PPC64) := $(call cc-option,-mtraceback=no)
powerpc: Don't add -mabi= flags when building with Clang When building pseries_defconfig, building vdso32 errors out: error: unknown target ABI 'elfv1' This happens because -m32 in clang changes the target to 32-bit, which does not allow the ABI to be changed. Commit 4dc831aa8813 ("powerpc: Fix compiling a BE kernel with a powerpc64le toolchain") added these flags to fix building big endian kernels with a little endian GCC. Clang doesn't need -mabi because the target triple controls the default value. -mlittle-endian and -mbig-endian manipulate the triple into either powerpc64-* or powerpc64le-*, which properly sets the default ABI. Adding a debug print out in the PPC64TargetInfo constructor after line 383 above shows this: $ echo | ./clang -E --target=powerpc64-linux -mbig-endian -o /dev/null - Default ABI: elfv1 $ echo | ./clang -E --target=powerpc64-linux -mlittle-endian -o /dev/null - Default ABI: elfv2 $ echo | ./clang -E --target=powerpc64le-linux -mbig-endian -o /dev/null - Default ABI: elfv1 $ echo | ./clang -E --target=powerpc64le-linux -mlittle-endian -o /dev/null - Default ABI: elfv2 Don't specify -mabi when building with clang to avoid the build error with -m32 and not change any code generation. -mcall-aixdesc is not an implemented flag in clang so it can be safely excluded as well, see commit 238abecde8ad ("powerpc: Don't use gcc specific options on clang"). pseries_defconfig successfully builds after this patch and powernv_defconfig and ppc44x_defconfig don't regress. Reviewed-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> [mpe: Trim clang links in change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191119045712.39633-2-natechancellor@gmail.com
2019-11-19 12:57:10 +08:00
ifndef CONFIG_CC_IS_CLANG
ifdef CONFIG_PPC64_ELF_ABI_V2
CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv2,$(call cc-option,-mcall-aixdesc))
AFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv2)
else
CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv1)
CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mcall-aixdesc)
AFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv1)
endif
powerpc: Don't add -mabi= flags when building with Clang When building pseries_defconfig, building vdso32 errors out: error: unknown target ABI 'elfv1' This happens because -m32 in clang changes the target to 32-bit, which does not allow the ABI to be changed. Commit 4dc831aa8813 ("powerpc: Fix compiling a BE kernel with a powerpc64le toolchain") added these flags to fix building big endian kernels with a little endian GCC. Clang doesn't need -mabi because the target triple controls the default value. -mlittle-endian and -mbig-endian manipulate the triple into either powerpc64-* or powerpc64le-*, which properly sets the default ABI. Adding a debug print out in the PPC64TargetInfo constructor after line 383 above shows this: $ echo | ./clang -E --target=powerpc64-linux -mbig-endian -o /dev/null - Default ABI: elfv1 $ echo | ./clang -E --target=powerpc64-linux -mlittle-endian -o /dev/null - Default ABI: elfv2 $ echo | ./clang -E --target=powerpc64le-linux -mbig-endian -o /dev/null - Default ABI: elfv1 $ echo | ./clang -E --target=powerpc64le-linux -mlittle-endian -o /dev/null - Default ABI: elfv2 Don't specify -mabi when building with clang to avoid the build error with -m32 and not change any code generation. -mcall-aixdesc is not an implemented flag in clang so it can be safely excluded as well, see commit 238abecde8ad ("powerpc: Don't use gcc specific options on clang"). pseries_defconfig successfully builds after this patch and powernv_defconfig and ppc44x_defconfig don't regress. Reviewed-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> [mpe: Trim clang links in change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191119045712.39633-2-natechancellor@gmail.com
2019-11-19 12:57:10 +08:00
endif
CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mcmodel=medium,$(call cc-option,-mminimal-toc))
CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mno-pointers-to-nested-functions)
powerpc/32: Avoid unsupported flags with clang When building for ppc32 with clang these flags are unsupported: -ffixed-r2 and -mmultiple llvm's lib/Target/PowerPC/PPCRegisterInfo.cpp marks r2 as reserved on when building for SVR4ABI and !ppc64: // The SVR4 ABI reserves r2 and r13 if (Subtarget.isSVR4ABI()) { // We only reserve r2 if we need to use the TOC pointer. If we have no // explicit uses of the TOC pointer (meaning we're a leaf function with // no constant-pool loads, etc.) and we have no potential uses inside an // inline asm block, then we can treat r2 has an ordinary callee-saved // register. const PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>(); if (!TM.isPPC64() || FuncInfo->usesTOCBasePtr() || MF.hasInlineAsm()) markSuperRegs(Reserved, PPC::R2); // System-reserved register markSuperRegs(Reserved, PPC::R13); // Small Data Area pointer register } This means we can safely omit -ffixed-r2 when building for 32-bit targets. The -mmultiple/-mno-multiple flags are not supported by clang, so platforms that might support multiple miss out on using multiple word instructions. We wrap these flags in cc-option so that when Clang gains support the kernel will be able use these flags. Clang 8 can then build a ppc44x_defconfig which boots in Qemu: make CC=clang-8 ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu- ppc44x_defconfig ./scripts/config -e CONFIG_DEVTMPFS -d DEVTMPFS_MOUNT make CC=clang-8 ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu- qemu-system-ppc -M bamboo \ -kernel arch/powerpc/boot/zImage \ -dtb arch/powerpc/boot/dts/bamboo.dtb \ -initrd ~/ppc32-440-rootfs.cpio \ -nographic -serial stdio -monitor pty -append "console=ttyS0" Link: https://github.com/ClangBuiltLinux/linux/issues/261 Link: https://bugs.llvm.org/show_bug.cgi?id=39556 Link: https://bugs.llvm.org/show_bug.cgi?id=39555 Signed-off-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-11-12 13:28:06 +08:00
# Clang unconditionally reserves r2 on ppc32 and does not support the flag
# https://bugs.llvm.org/show_bug.cgi?id=39555
CFLAGS-$(CONFIG_PPC32) := $(call cc-option, -ffixed-r2)
# Clang doesn't support -mmultiple / -mno-multiple
# https://bugs.llvm.org/show_bug.cgi?id=39556
CFLAGS-$(CONFIG_PPC32) += $(call cc-option, $(MULTIPLEWORD))
CFLAGS-$(CONFIG_PPC32) += $(call cc-option,-mno-readonly-in-sdata)
ifdef CONFIG_PPC_BOOK3S_64
ifdef CONFIG_CPU_LITTLE_ENDIAN
CFLAGS-$(CONFIG_GENERIC_CPU) += -mcpu=power8
CFLAGS-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=power9,-mtune=power8)
else
CFLAGS-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=power7,$(call cc-option,-mtune=power5))
CFLAGS-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mcpu=power5,-mcpu=power4)
endif
else ifdef CONFIG_PPC_BOOK3E_64
CFLAGS-$(CONFIG_GENERIC_CPU) += -mcpu=powerpc64
endif
ifdef CONFIG_FUNCTION_TRACER
CC_FLAGS_FTRACE := -pg
ifdef CONFIG_MPROFILE_KERNEL
CC_FLAGS_FTRACE += -mprofile-kernel
endif
endif
CFLAGS-$(CONFIG_TARGET_CPU_BOOL) += $(call cc-option,-mcpu=$(CONFIG_TARGET_CPU))
# Altivec option not allowed with e500mc64 in GCC.
ifdef CONFIG_ALTIVEC
E5500_CPU := -mcpu=powerpc64
else
E5500_CPU := $(call cc-option,-mcpu=e500mc64,-mcpu=powerpc64)
endif
CFLAGS-$(CONFIG_E5500_CPU) += $(E5500_CPU)
CFLAGS-$(CONFIG_E6500_CPU) += $(call cc-option,-mcpu=e6500,$(E5500_CPU))
ifdef CONFIG_PPC32
ifdef CONFIG_PPC_E500MC
CFLAGS-y += $(call cc-option,-mcpu=e500mc,-mcpu=powerpc)
else
CFLAGS-$(CONFIG_E500) += $(call cc-option,-mcpu=8540 -msoft-float,-mcpu=powerpc)
endif
endif
powerpc: Fix 64 bit builds with binutils 2.24 With binutils 2.24, various 64 bit builds fail with relocation errors such as arch/powerpc/kernel/built-in.o: In function `exc_debug_crit_book3e': (.text+0x165ee): relocation truncated to fit: R_PPC64_ADDR16_HI against symbol `interrupt_base_book3e' defined in .text section in arch/powerpc/kernel/built-in.o arch/powerpc/kernel/built-in.o: In function `exc_debug_crit_book3e': (.text+0x16602): relocation truncated to fit: R_PPC64_ADDR16_HI against symbol `interrupt_end_book3e' defined in .text section in arch/powerpc/kernel/built-in.o The assembler maintainer says: I changed the ABI, something that had to be done but unfortunately happens to break the booke kernel code. When building up a 64-bit value with lis, ori, shl, oris, ori or similar sequences, you now should use @high and @higha in place of @h and @ha. @h and @ha (and their associated relocs R_PPC64_ADDR16_HI and R_PPC64_ADDR16_HA) now report overflow if the value is out of 32-bit signed range. ie. @h and @ha assume you're building a 32-bit value. This is needed to report out-of-range -mcmodel=medium toc pointer offsets in @toc@h and @toc@ha expressions, and for consistency I did the same for all other @h and @ha relocs. Replacing @h with @high in one strategic location fixes the relocation errors. This has to be done conditionally since the assembler either supports @h or @high but not both. Cc: <stable@vger.kernel.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-05-16 00:33:42 +08:00
asinstr := $(call as-instr,lis 9$(comma)foo@high,-DHAVE_AS_ATHIGH=1)
KBUILD_CPPFLAGS += -I $(srctree)/arch/$(ARCH) $(asinstr)
KBUILD_AFLAGS += $(AFLAGS-y)
KBUILD_CFLAGS += $(call cc-option,-msoft-float)
KBUILD_CFLAGS += -pipe $(CFLAGS-y)
CPP = $(CC) -E $(KBUILD_CFLAGS)
CHECKFLAGS += -m$(BITS) -D__powerpc__ -D__powerpc$(BITS)__
ifdef CONFIG_CPU_BIG_ENDIAN
CHECKFLAGS += -D__BIG_ENDIAN__
else
CHECKFLAGS += -D__LITTLE_ENDIAN__
endif
ifdef CONFIG_476FPE_ERR46
KBUILD_LDFLAGS_MODULE += --ppc476-workaround \
-T $(srctree)/arch/powerpc/platforms/44x/ppc476_modules.lds
endif
# No AltiVec or VSX instructions when building kernel
KBUILD_CFLAGS += $(call cc-option,-mno-altivec)
KBUILD_CFLAGS += $(call cc-option,-mno-vsx)
# No SPE instruction when building kernel
# (We use all available options to help semi-broken compilers)
KBUILD_CFLAGS += $(call cc-option,-mno-spe)
KBUILD_CFLAGS += $(call cc-option,-mspe=no)
# Don't emit .eh_frame since we have no use for it
KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
# Never use string load/store instructions as they are
# often slow when they are implemented at all
KBUILD_CFLAGS += $(call cc-option,-mno-string)
cpu-as-$(CONFIG_40x) += -Wa,-m405
cpu-as-$(CONFIG_44x) += -Wa,-m440
cpu-as-$(CONFIG_ALTIVEC) += $(call as-option,-Wa$(comma)-maltivec)
cpu-as-$(CONFIG_E500) += -Wa,-me500
powerpc/Makefile: Fix PPC_BOOK3S_64 ASFLAGS Ever since commit 15a3204d24a3 ("powerpc/64s: Set assembler machine type to POWER4") we force -mpower4 to be passed to the assembler irrespective of the CFLAGS used (for Book3s 64). When building a powerpc64 kernel with clang, clang will not add -many to the assembler flags, so any instructions that the compiler has generated that are not available on power4 will cause an error: /usr/bin/as -a64 -mppc64 -mlittle-endian -mpower8 \ -I ./arch/powerpc/include -I ./arch/powerpc/include/generated \ -I ./include -I ./arch/powerpc/include/uapi \ -I ./arch/powerpc/include/generated/uapi -I ./include/uapi \ -I ./include/generated/uapi -I arch/powerpc -I arch/powerpc \ -maltivec -mpower4 -o init/do_mounts.o /tmp/do_mounts-3b0a3d.s /tmp/do_mounts-51ce54.s:748: Error: unrecognized opcode: `isel' GCC does include -many, so the GCC driven gas call will succeed: as -v -I ./arch/powerpc/include -I ./arch/powerpc/include/generated -I ./include -I ./arch/powerpc/include/uapi -I ./arch/powerpc/include/generated/uapi -I ./include/uapi -I ./include/generated/uapi -I arch/powerpc -I arch/powerpc -a64 -mpower8 -many -mlittle -maltivec -mpower4 -o init/do_mounts.o Note that isel is power7 and above for IBM CPUs. GCC only generates it for Power9 and above, but the above test was run against the clang generated assembly. Peter Bergner explains: When using -many -mpower4, gas will first try and find a matching power4 mnemonic and failing that, it will then allow any valid mnemonic that gas knows about. GCC's use of -many predates me though. IIRC, Alan looked at trying to remove it, but I forget why he didn't. Could be either a gcc or gas issue at the time. I'm not sure whether issue still exists or not. He and I have modified how gas works internally a fair amount since he tried removing gcc use of -many. I will also note that when using -many, gas will choose the first mnemonic that matches in the mnemonic table and we have (mostly) sorted the table so that server mnemonics show up earlier in the table than other mnemonics, so they'll be seen/chosen first. By explicitly setting -many we can build with Clang and GCC while retaining the -mpower4 option. Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-11 10:43:03 +08:00
# When using '-many -mpower4' gas will first try and find a matching power4
# mnemonic and failing that it will allow any valid mnemonic that GAS knows
# about. GCC will pass -many to GAS when assembling, clang does not.
# LLVM IAS doesn't understand either flag: https://github.com/ClangBuiltLinux/linux/issues/675
# but LLVM IAS only supports ISA >= 2.06 for Book3S 64 anyway...
cpu-as-$(CONFIG_PPC_BOOK3S_64) += $(call as-option,-Wa$(comma)-mpower4) $(call as-option,-Wa$(comma)-many)
cpu-as-$(CONFIG_PPC_E500MC) += $(call as-option,-Wa$(comma)-me500mc)
KBUILD_AFLAGS += $(cpu-as-y)
KBUILD_CFLAGS += $(cpu-as-y)
KBUILD_AFLAGS += $(aflags-y)
KBUILD_CFLAGS += $(cflags-y)
head-$(CONFIG_PPC64) := arch/powerpc/kernel/head_64.o
head-$(CONFIG_PPC_BOOK3S_32) := arch/powerpc/kernel/head_book3s_32.o
head-$(CONFIG_PPC_8xx) := arch/powerpc/kernel/head_8xx.o
head-$(CONFIG_40x) := arch/powerpc/kernel/head_40x.o
head-$(CONFIG_44x) := arch/powerpc/kernel/head_44x.o
head-$(CONFIG_FSL_BOOKE) := arch/powerpc/kernel/head_fsl_booke.o
head-$(CONFIG_PPC64) += arch/powerpc/kernel/entry_64.o
head-$(CONFIG_PPC_FPU) += arch/powerpc/kernel/fpu.o
head-$(CONFIG_ALTIVEC) += arch/powerpc/kernel/vector.o
head-$(CONFIG_PPC_OF_BOOT_TRAMPOLINE) += arch/powerpc/kernel/prom_init.o
# Default to zImage, override when needed
[POWERPC] bootwrapper: Build multiple cuImages Currently, the kernel uses CONFIG_DEVICE_TREE to wrap a kernel image with a fdt blob which means for any given configuration only one dts file can be selected and so support for only one board can be built This moves the selection of the default .dts file out of the kernel config and into the bootwrapper makefile. The makefile chooses which images to build based on the kernel config and the dts source file name is taken directly from the image name. For example "cuImage.ebony" will use "ebony.dts" as the device tree source file. In addition, this patch allows a specific image to be requested from the command line by adding "cuImage.%" and "treeImage.%" targets to the list of valid built targets in arch/powerpc/Makefile. This allows the default dts selection to be overridden. Another advantage to this change is it allows a single defconfig to be supplied for all boards using the same chip family and only differing in the device tree. Important note: This patch adds two new zImage targets; zImage.dtb.% and zImage.dtb.initrd.% for zImages with embedded dtb files. Currently there are 5 platforms which require this: ps3, ep405, mpc885ads, ep88xc, adder875-redboot and ep8248e. This patch *changes the zImage filenames* for those platforms. ie. 'zImage.ps3' is now 'zImage.dtb.ps3'. This new zImage.dtb targets were added so that the .dts file could be part of the dependancies list for building them. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-02-07 02:18:34 +08:00
all: zImage
# With make 3.82 we cannot mix normal and wildcard targets
BOOT_TARGETS1 := zImage zImage.initrd uImage
BOOT_TARGETS2 := zImage% dtbImage% treeImage.% cuImage.% simpleImage.% uImage.%
PHONY += $(BOOT_TARGETS1) $(BOOT_TARGETS2)
boot := arch/$(ARCH)/boot
$(BOOT_TARGETS1): vmlinux
$(Q)$(MAKE) $(build)=$(boot) $(patsubst %,$(boot)/%,$@)
$(BOOT_TARGETS2): vmlinux
$(Q)$(MAKE) $(build)=$(boot) $(patsubst %,$(boot)/%,$@)
PHONY += bootwrapper_install
bootwrapper_install:
$(Q)$(MAKE) $(build)=$(boot) $(patsubst %,$(boot)/%,$@)
powerpc/configs: Replace pseries_le_defconfig with a Makefile target using merge_config Rather than continuing to maintain a copy of pseries_defconfig with CONFIG_CPU_LITTLE_ENDIAN enabled, use the generic merge_config script and use an le.config to enable little endian on top of pseries_defconfig without the need for a duplicated _defconfig file. This method will require less maintenance in the future and will ensure that both 'defconfigs' are always in sync. It is worth noting that the seemingly more simple approach of: pseries_le_defconfig: pseries_defconfig $(Q)$(MAKE) le.config Will not work when building using O=builddir. The obvious fix to that: pseries_le_defconfig: $(Q)$(MAKE) -f $(srctree)/Makefile pseries_defconfig le.config Also does not work. This is because if we have for example: config FOO depends on CPU_BIG_ENDIAN select BAR Then BAR will be enabled by the first call to kconfig (via pseries_defconfig), and then will remain enabled after we merge le.config, even though FOO will have been turned off. The solution is to ensure to only invoke the kconfig logic once, after we have merged all the config fragments. This ensures nothing is select'ed on that should then be disabled by the later merged configs. This is done through the explicit call to make olddefconfig Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Reviewed-by: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> [mpe: Massage change log, fix white space and use ARCH not SRCARCH] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-05-26 09:36:57 +08:00
# Used to create 'merged defconfigs'
# To use it $(call) it with the first argument as the base defconfig
# and the second argument as a space separated list of .config files to merge,
# without the .config suffix.
define merge_into_defconfig
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
-m -O $(objtree) $(srctree)/arch/$(ARCH)/configs/$(1) \
$(foreach config,$(2),$(srctree)/arch/$(ARCH)/configs/$(config).config)
+$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
endef
PHONY += pseries_le_defconfig
pseries_le_defconfig:
$(call merge_into_defconfig,pseries_defconfig,le)
PHONY += ppc64le_defconfig
ppc64le_defconfig:
$(call merge_into_defconfig,ppc64_defconfig,le)
PHONY += ppc64le_guest_defconfig
ppc64le_guest_defconfig:
$(call merge_into_defconfig,ppc64_defconfig,le guest)
PHONY += ppc64_guest_defconfig
ppc64_guest_defconfig:
$(call merge_into_defconfig,ppc64_defconfig,be guest)
PHONY += powernv_be_defconfig
powernv_be_defconfig:
$(call merge_into_defconfig,powernv_defconfig,be)
PHONY += mpc85xx_defconfig
mpc85xx_defconfig:
$(call merge_into_defconfig,mpc85xx_base.config,\
85xx-32bit 85xx-hw fsl-emb-nonhw)
PHONY += mpc85xx_smp_defconfig
mpc85xx_smp_defconfig:
$(call merge_into_defconfig,mpc85xx_base.config,\
85xx-32bit 85xx-smp 85xx-hw fsl-emb-nonhw)
PHONY += corenet32_smp_defconfig
corenet32_smp_defconfig:
$(call merge_into_defconfig,corenet_base.config,\
85xx-32bit 85xx-smp 85xx-hw fsl-emb-nonhw dpaa)
PHONY += corenet64_smp_defconfig
corenet64_smp_defconfig:
$(call merge_into_defconfig,corenet_base.config,\
85xx-64bit 85xx-smp altivec 85xx-hw fsl-emb-nonhw dpaa)
PHONY += mpc86xx_defconfig
mpc86xx_defconfig:
$(call merge_into_defconfig,mpc86xx_base.config,\
86xx-hw fsl-emb-nonhw)
PHONY += mpc86xx_smp_defconfig
mpc86xx_smp_defconfig:
$(call merge_into_defconfig,mpc86xx_base.config,\
86xx-smp 86xx-hw fsl-emb-nonhw)
PHONY += ppc32_allmodconfig
ppc32_allmodconfig:
$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/book3s_32.config \
-f $(srctree)/Makefile allmodconfig
PHONY += ppc_defconfig
ppc_defconfig:
$(call merge_into_defconfig,book3s_32.config,)
PHONY += ppc64le_allmodconfig
ppc64le_allmodconfig:
$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/le.config \
-f $(srctree)/Makefile allmodconfig
PHONY += ppc64le_allnoconfig
ppc64le_allnoconfig:
$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/ppc64le.config \
-f $(srctree)/Makefile allnoconfig
PHONY += ppc64_book3e_allmodconfig
ppc64_book3e_allmodconfig:
$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/85xx-64bit.config \
-f $(srctree)/Makefile allmodconfig
PHONY += ppc32_randconfig
ppc32_randconfig:
$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/32-bit.config \
-f $(srctree)/Makefile randconfig
PHONY += ppc64_randconfig
ppc64_randconfig:
$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/64-bit.config \
-f $(srctree)/Makefile randconfig
define archhelp
@echo '* zImage - Build default images selected by kernel config'
@echo ' zImage.* - Compressed kernel image (arch/$(ARCH)/boot/zImage.*)'
@echo ' uImage - U-Boot native image format'
@echo ' cuImage.<dt> - Backwards compatible U-Boot image for older'
@echo ' versions which do not support device trees'
@echo ' dtbImage.<dt> - zImage with an embedded device tree blob'
@echo ' simpleImage.<dt> - Firmware independent image.'
@echo ' treeImage.<dt> - Support for older IBM 4xx firmware (not U-Boot)'
@echo ' install - Install kernel using'
kbuild: use INSTALLKERNEL to select customized installkernel script Replace the use of CROSS_COMPILE to select a customized installkernel script with the possibility to set INSTALLKERNEL to select a custom installkernel script when running make: make INSTALLKERNEL=arm-installkernel install With this patch we are now more consistent across different architectures - they did not all support use of CROSS_COMPILE. The use of CROSS_COMPILE was a hack as this really belongs to gcc/binutils and the installkernel script does not change just because we change toolchain. The use of CROSS_COMPILE caused troubles with an upcoming patch that saves CROSS_COMPILE when a kernel is built - it would no longer be installable. [Thanks to Peter Z. for this hint] This patch undos what Ian did in commit: 0f8e2d62fa04441cd12c08ce521e84e5bd3f8a46 ("use ${CROSS_COMPILE}installkernel in arch/*/boot/install.sh") The patch has been lightly tested on x86 only - but all changes looks obvious. Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Mike Frysinger <vapier@gentoo.org> [blackfin] Acked-by: Russell King <linux@arm.linux.org.uk> [arm] Acked-by: Paul Mundt <lethal@linux-sh.org> [sh] Acked-by: "H. Peter Anvin" <hpa@zytor.com> [x86] Cc: Ian Campbell <icampbell@arcom.com> Cc: Tony Luck <tony.luck@intel.com> [ia64] Cc: Fenghua Yu <fenghua.yu@intel.com> [ia64] Cc: Hirokazu Takata <takata@linux-m32r.org> [m32r] Cc: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Cc: Kyle McMartin <kyle@mcmartin.ca> [parisc] Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> [powerpc] Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> [s390] Cc: Thomas Gleixner <tglx@linutronix.de> [x86] Cc: Ingo Molnar <mingo@redhat.com> [x86] Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-07-21 03:37:11 +08:00
@echo ' (your) ~/bin/$(INSTALLKERNEL) or'
@echo ' (distribution) /sbin/$(INSTALLKERNEL) or'
@echo ' install to $$(INSTALL_PATH) and run lilo'
@echo ' *_defconfig - Select default config from arch/$(ARCH)/configs'
@echo ''
@echo ' Targets with <dt> embed a device tree blob inside the image'
@echo ' These targets support board with firmware that does not'
@echo ' support passing a device tree directly. Replace <dt> with the'
@echo ' name of a dts file from the arch/$(ARCH)/boot/dts/ directory'
@echo ' (minus the .dts extension).'
endef
PHONY += install
install:
$(call cmd,install)
ifeq ($(KBUILD_EXTMOD),)
# We need to generate vdso-offsets.h before compiling certain files in kernel/.
# In order to do that, we should use the archprepare target, but we can't since
# asm-offsets.h is included in some files used to generate vdso-offsets.h, and
# asm-offsets.h is built in prepare0, for which archprepare is a dependency.
# Therefore we need to generate the header after prepare0 has been made, hence
# this hack.
prepare: vdso_prepare
vdso_prepare: prepare0
$(if $(CONFIG_VDSO32),$(Q)$(MAKE) \
$(build)=arch/powerpc/kernel/vdso include/generated/vdso32-offsets.h)
$(if $(CONFIG_PPC64),$(Q)$(MAKE) \
$(build)=arch/powerpc/kernel/vdso include/generated/vdso64-offsets.h)
endif
archprepare: checkbin
archheaders:
$(Q)$(MAKE) $(build)=arch/powerpc/kernel/syscalls all
powerpc/32: add stack protector support This functionality was tentatively added in the past (commit 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support")) but had to be reverted (commit f2574030b0e3 ("powerpc: Revert the initial stack protector support") because of GCC implementing it differently whether it had been built with libc support or not. Now, GCC offers the possibility to manually set the stack-protector mode (global or tls) regardless of libc support. This time, the patch selects HAVE_STACKPROTECTOR only if -mstack-protector-guard=tls is supported by GCC. On PPC32, as register r2 points to current task_struct at all time, the stack_canary located inside task_struct can be used directly by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=offsetof(struct task_struct, stack_canary)) The protector is disabled for prom_init and bootx_init as it is too early to handle it properly. $ echo CORRUPT_STACK > /sys/kernel/debug/provoke-crash/DIRECT [ 134.943666] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: lkdtm_CORRUPT_STACK+0x64/0x64 [ 134.943666] [ 134.955414] CPU: 0 PID: 283 Comm: sh Not tainted 4.18.0-s3k-dev-12143-ga3272be41209 #835 [ 134.963380] Call Trace: [ 134.965860] [c6615d60] [c001f76c] panic+0x118/0x260 (unreliable) [ 134.971775] [c6615dc0] [c001f654] panic+0x0/0x260 [ 134.976435] [c6615dd0] [c032c368] lkdtm_CORRUPT_STACK_STRONG+0x0/0x64 [ 134.982769] [c6615e00] [ffffffff] 0xffffffff Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-27 15:05:53 +08:00
ifdef CONFIG_STACKPROTECTOR
prepare: stack_protector_prepare
PHONY += stack_protector_prepare
powerpc/32: add stack protector support This functionality was tentatively added in the past (commit 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support")) but had to be reverted (commit f2574030b0e3 ("powerpc: Revert the initial stack protector support") because of GCC implementing it differently whether it had been built with libc support or not. Now, GCC offers the possibility to manually set the stack-protector mode (global or tls) regardless of libc support. This time, the patch selects HAVE_STACKPROTECTOR only if -mstack-protector-guard=tls is supported by GCC. On PPC32, as register r2 points to current task_struct at all time, the stack_canary located inside task_struct can be used directly by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=offsetof(struct task_struct, stack_canary)) The protector is disabled for prom_init and bootx_init as it is too early to handle it properly. $ echo CORRUPT_STACK > /sys/kernel/debug/provoke-crash/DIRECT [ 134.943666] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: lkdtm_CORRUPT_STACK+0x64/0x64 [ 134.943666] [ 134.955414] CPU: 0 PID: 283 Comm: sh Not tainted 4.18.0-s3k-dev-12143-ga3272be41209 #835 [ 134.963380] Call Trace: [ 134.965860] [c6615d60] [c001f76c] panic+0x118/0x260 (unreliable) [ 134.971775] [c6615dc0] [c001f654] panic+0x0/0x260 [ 134.976435] [c6615dd0] [c032c368] lkdtm_CORRUPT_STACK_STRONG+0x0/0x64 [ 134.982769] [c6615e00] [ffffffff] 0xffffffff Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-27 15:05:53 +08:00
stack_protector_prepare: prepare0
ifdef CONFIG_PPC64
$(eval KBUILD_CFLAGS += -mstack-protector-guard-offset=$(shell awk '{if ($$2 == "PACA_CANARY") print $$3;}' include/generated/asm-offsets.h))
else
powerpc/32: add stack protector support This functionality was tentatively added in the past (commit 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support")) but had to be reverted (commit f2574030b0e3 ("powerpc: Revert the initial stack protector support") because of GCC implementing it differently whether it had been built with libc support or not. Now, GCC offers the possibility to manually set the stack-protector mode (global or tls) regardless of libc support. This time, the patch selects HAVE_STACKPROTECTOR only if -mstack-protector-guard=tls is supported by GCC. On PPC32, as register r2 points to current task_struct at all time, the stack_canary located inside task_struct can be used directly by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=offsetof(struct task_struct, stack_canary)) The protector is disabled for prom_init and bootx_init as it is too early to handle it properly. $ echo CORRUPT_STACK > /sys/kernel/debug/provoke-crash/DIRECT [ 134.943666] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: lkdtm_CORRUPT_STACK+0x64/0x64 [ 134.943666] [ 134.955414] CPU: 0 PID: 283 Comm: sh Not tainted 4.18.0-s3k-dev-12143-ga3272be41209 #835 [ 134.963380] Call Trace: [ 134.965860] [c6615d60] [c001f76c] panic+0x118/0x260 (unreliable) [ 134.971775] [c6615dc0] [c001f654] panic+0x0/0x260 [ 134.976435] [c6615dd0] [c032c368] lkdtm_CORRUPT_STACK_STRONG+0x0/0x64 [ 134.982769] [c6615e00] [ffffffff] 0xffffffff Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-27 15:05:53 +08:00
$(eval KBUILD_CFLAGS += -mstack-protector-guard-offset=$(shell awk '{if ($$2 == "TASK_CANARY") print $$3;}' include/generated/asm-offsets.h))
endif
endif
powerpc/32: add stack protector support This functionality was tentatively added in the past (commit 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support")) but had to be reverted (commit f2574030b0e3 ("powerpc: Revert the initial stack protector support") because of GCC implementing it differently whether it had been built with libc support or not. Now, GCC offers the possibility to manually set the stack-protector mode (global or tls) regardless of libc support. This time, the patch selects HAVE_STACKPROTECTOR only if -mstack-protector-guard=tls is supported by GCC. On PPC32, as register r2 points to current task_struct at all time, the stack_canary located inside task_struct can be used directly by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=offsetof(struct task_struct, stack_canary)) The protector is disabled for prom_init and bootx_init as it is too early to handle it properly. $ echo CORRUPT_STACK > /sys/kernel/debug/provoke-crash/DIRECT [ 134.943666] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: lkdtm_CORRUPT_STACK+0x64/0x64 [ 134.943666] [ 134.955414] CPU: 0 PID: 283 Comm: sh Not tainted 4.18.0-s3k-dev-12143-ga3272be41209 #835 [ 134.963380] Call Trace: [ 134.965860] [c6615d60] [c001f76c] panic+0x118/0x260 (unreliable) [ 134.971775] [c6615dc0] [c001f654] panic+0x0/0x260 [ 134.976435] [c6615dd0] [c032c368] lkdtm_CORRUPT_STACK_STRONG+0x0/0x64 [ 134.982769] [c6615e00] [ffffffff] 0xffffffff Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-27 15:05:53 +08:00
PHONY += checkbin
# Check toolchain versions:
# - gcc-4.6 is the minimum kernel-wide version so nothing required.
checkbin:
powerpc/toc: Future proof kernel toc This patch future-proofs the kernel against linker changes that might put the toc pointer at some location other than .got+0x8000, by replacing __toc_start+0x8000 with .TOC. throughout. If the kernel's idea of the toc pointer doesn't agree with the linker, bad things happen. prom_init.c code relocating its toc is also changed so that a symbolic __prom_init_toc_start toc-pointer relative address is calculated rather than assuming that it is always at toc-pointer - 0x8000. The length calculations loading values from the toc are also avoided. It's a little incestuous to do that with unreloc_toc picking up adjusted values (which is fine in practice, they both adjust by the same amount if all goes well). I've also changed the way .got is aligned in vmlinux.lds and zImage.lds, mostly so that dumping out section info by objdump or readelf plainly shows the alignment is 256. This linker script feature was added 2005-09-27, available in FSF binutils releases from 2.17 onwards. Should be safe to use in the kernel, I think. Finally, put *(.got) before the prom_init.o entry which only needs *(.toc), so that the GOT header goes in the correct place. I don't believe this makes any difference for the kernel as it would for dynamic objects being loaded by ld.so. That change is just to stop lusers who blindly copy kernel scripts being led astray. Of course, this change needs the prom_init.c changes. Some notes on .toc and .got. .toc is a compiler generated section of addresses. .got is a linker generated section of addresses, generally built when the linker sees R_*_*GOT* relocations. In the case of powerpc64 ld.bfd, there are multiple generated .got sections, one per input object file. So you can somewhat reasonably write in a linker script an input section statement like *prom_init.o(.got .toc) to mean "the .got and .toc section for files matching *prom_init.o". On other architectures that doesn't make sense, because the linker generally has just one .got section. Even on powerpc64, note well that the GOT entries for prom_init.o may be merged with GOT entries from other objects. That means that if prom_init.o references, say, _end via some GOT relocation, and some other object also references _end via a GOT relocation, the GOT entry for _end may be in the range __prom_init_toc_start to __prom_init_toc_end and if the kernel does something special to GOT/TOC entries in that range then the value of _end as seen by objects other than prom_init.o will be affected. On the other hand the GOT entry for _end may not be in the range __prom_init_toc_start to __prom_init_toc_end. Which way it turns out is deterministic but a detail of linker operation that should not be relied on. A feature of ld.bfd is that input .toc (and .got) sections matching one linker input section statement may be sorted, to put entries used by small-model code first, near the toc base. This is why scripts for powerpc64 normally use *(.got .toc) rather than *(.got) *(.toc), since the first form allows more freedom to sort. Another feature of ld.bfd is that indirect addressing sequences using the GOT/TOC may be edited by the linker to relative addressing. In many cases relative addressing would be emitted by gcc for -mcmodel=medium if you appropriately decorate variable declarations with non-default visibility. The original patch is here: https://lore.kernel.org/linuxppc-dev/20210310034813.GM6042@bubble.grove.modra.org/ Signed-off-by: Alan Modra <amodra@au1.ibm.com> [aik: removed non-relocatable which is gone in 24d33ac5b8ffb] [aik: added <=2.24 check] [aik: because of llvm-as, kernel_toc_addr() uses "mr" instead of global register variable] Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211221055904.555763-2-aik@ozlabs.ru
2021-12-21 13:58:59 +08:00
@if test "x${CONFIG_LD_IS_LLD}" != "xy" -a \
"x$(call ld-ifversion, -le, 22400, y)" = "xy" ; then \
echo -n '*** binutils 2.24 miscompiles weak symbols ' ; \
echo 'in some circumstances.' ; \
powerpc/toc: Future proof kernel toc This patch future-proofs the kernel against linker changes that might put the toc pointer at some location other than .got+0x8000, by replacing __toc_start+0x8000 with .TOC. throughout. If the kernel's idea of the toc pointer doesn't agree with the linker, bad things happen. prom_init.c code relocating its toc is also changed so that a symbolic __prom_init_toc_start toc-pointer relative address is calculated rather than assuming that it is always at toc-pointer - 0x8000. The length calculations loading values from the toc are also avoided. It's a little incestuous to do that with unreloc_toc picking up adjusted values (which is fine in practice, they both adjust by the same amount if all goes well). I've also changed the way .got is aligned in vmlinux.lds and zImage.lds, mostly so that dumping out section info by objdump or readelf plainly shows the alignment is 256. This linker script feature was added 2005-09-27, available in FSF binutils releases from 2.17 onwards. Should be safe to use in the kernel, I think. Finally, put *(.got) before the prom_init.o entry which only needs *(.toc), so that the GOT header goes in the correct place. I don't believe this makes any difference for the kernel as it would for dynamic objects being loaded by ld.so. That change is just to stop lusers who blindly copy kernel scripts being led astray. Of course, this change needs the prom_init.c changes. Some notes on .toc and .got. .toc is a compiler generated section of addresses. .got is a linker generated section of addresses, generally built when the linker sees R_*_*GOT* relocations. In the case of powerpc64 ld.bfd, there are multiple generated .got sections, one per input object file. So you can somewhat reasonably write in a linker script an input section statement like *prom_init.o(.got .toc) to mean "the .got and .toc section for files matching *prom_init.o". On other architectures that doesn't make sense, because the linker generally has just one .got section. Even on powerpc64, note well that the GOT entries for prom_init.o may be merged with GOT entries from other objects. That means that if prom_init.o references, say, _end via some GOT relocation, and some other object also references _end via a GOT relocation, the GOT entry for _end may be in the range __prom_init_toc_start to __prom_init_toc_end and if the kernel does something special to GOT/TOC entries in that range then the value of _end as seen by objects other than prom_init.o will be affected. On the other hand the GOT entry for _end may not be in the range __prom_init_toc_start to __prom_init_toc_end. Which way it turns out is deterministic but a detail of linker operation that should not be relied on. A feature of ld.bfd is that input .toc (and .got) sections matching one linker input section statement may be sorted, to put entries used by small-model code first, near the toc base. This is why scripts for powerpc64 normally use *(.got .toc) rather than *(.got) *(.toc), since the first form allows more freedom to sort. Another feature of ld.bfd is that indirect addressing sequences using the GOT/TOC may be edited by the linker to relative addressing. In many cases relative addressing would be emitted by gcc for -mcmodel=medium if you appropriately decorate variable declarations with non-default visibility. The original patch is here: https://lore.kernel.org/linuxppc-dev/20210310034813.GM6042@bubble.grove.modra.org/ Signed-off-by: Alan Modra <amodra@au1.ibm.com> [aik: removed non-relocatable which is gone in 24d33ac5b8ffb] [aik: added <=2.24 check] [aik: because of llvm-as, kernel_toc_addr() uses "mr" instead of global register variable] Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211221055904.555763-2-aik@ozlabs.ru
2021-12-21 13:58:59 +08:00
echo '*** binutils 2.23 do not define the TOC symbol ' ; \
echo -n '*** Please use a different binutils version.' ; \
false ; \
fi