Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 431 insertions, 0 deletions

diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
new file mode 100644
index 000000000..9385db478
--- /dev/null
+++ b/arch/powerpc/Makefile
@@ -0,0 +1,431 @@
+# 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
+#
+
+ifdef cross_compiling
+  ifeq ($(CROSS_COMPILE),)
+    # Auto detect cross compiler prefix.
+    # Look for: (powerpc(64(le)?)?)(-unknown)?-linux(-gnu)?-
+    CC_ARCHES := powerpc powerpc64 powerpc64le
+    CC_SUFFIXES := linux linux-gnu unknown-linux-gnu
+    CROSS_COMPILE := $(call cc-cross-prefix, $(foreach a,$(CC_ARCHES), \
+                       $(foreach s,$(CC_SUFFIXES),$(a)-$(s)-)))
+  endif
+endif
+
+HAS_BIARCH	:= $(call cc-option-yn, -m32)
+
+# Set default 32 bits cross compilers for vdso and boot wrapper
+CROSS32_COMPILE ?=
+
+# If we're on a ppc/ppc64/ppc64le machine use that defconfig, otherwise just use
+# ppc64le_defconfig because we have nothing better to go on.
+uname := $(shell uname -m)
+KBUILD_DEFCONFIG := $(if $(filter ppc%,$(uname)),$(uname),ppc64le)_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))
+
+ifeq ($(CONFIG_PPC64)$(CONFIG_LD_IS_BFD),yy)
+# 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 += $(objtree)/arch/powerpc/lib/crtsavres.o
+endif
+
+ifdef CONFIG_PPC64
+KBUILD_RUSTFLAGS	+= --target=powerpc64le-unknown-linux-gnu
+KBUILD_RUSTFLAGS	+= -Ctarget-feature=-mma,-vsx,-hard-float,-altivec
+else
+KBUILD_RUSTFLAGS	+= --target=powerpc-unknown-linux-gnu
+endif
+
+ifdef CONFIG_CPU_LITTLE_ENDIAN
+KBUILD_CPPFLAGS	+= -mlittle-endian
+KBUILD_LDFLAGS	+= -EL
+LDEMULATION	:= lppc
+GNUTARGET	:= powerpcle
+MULTIPLEWORD	:= -mno-multiple
+KBUILD_CFLAGS_MODULE += $(call cc-option,-mno-save-toc-indirect)
+else
+KBUILD_CPPFLAGS	+= $(call cc-option,-mbig-endian)
+KBUILD_LDFLAGS	+= -EB
+LDEMULATION	:= ppc
+GNUTARGET	:= powerpc
+MULTIPLEWORD	:= -mmultiple
+endif
+
+ifdef CONFIG_PPC64
+ifndef CONFIG_CC_IS_CLANG
+cflags-$(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
+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 ($(HAS_BIARCH),y)
+KBUILD_CPPFLAGS	+= -m$(BITS)
+KBUILD_AFLAGS	+= -m$(BITS)
+KBUILD_LDFLAGS	+= -m elf$(BITS)$(LDEMULATION)
+endif
+
+LDFLAGS_vmlinux-y := -Bstatic
+LDFLAGS_vmlinux-$(CONFIG_RELOCATABLE) := -pie --no-dynamic-linker
+LDFLAGS_vmlinux-$(CONFIG_RELOCATABLE) += -z notext
+LDFLAGS_vmlinux	:= $(LDFLAGS_vmlinux-y)
+
+ifdef CONFIG_PPC64
+ifndef CONFIG_PPC_KERNEL_PCREL
+	# -mcmodel=medium breaks modules because it uses 32bit offsets from
+	# the TOC pointer to create pointers where possible. Pointers into the
+	# percpu data area are created by this method.
+	#
+	# The kernel module loader relocates the percpu data section from the
+	# original location (starting with 0xd...) to somewhere in the base
+	# kernel percpu data space (starting with 0xc...). We need a full
+	# 64bit relocation for this to work, hence -mcmodel=large.
+	KBUILD_CFLAGS_MODULE += -mcmodel=large
+endif
+endif
+
+CFLAGS-$(CONFIG_PPC64)	:= $(call cc-option,-mtraceback=no)
+ifdef CONFIG_PPC64_ELF_ABI_V2
+CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mabi=elfv2,$(call cc-option,-mcall-aixdesc))
+else
+ifndef CONFIG_CC_IS_CLANG
+CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mabi=elfv1)
+CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mcall-aixdesc)
+endif
+endif
+CFLAGS-$(CONFIG_PPC64)	+= -mcmodel=medium
+CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mno-pointers-to-nested-functions)
+CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mlong-double-128)
+
+# Clang unconditionally reserves r2 on ppc32 and does not support the flag
+# https://llvm.org/pr39555
+CFLAGS-$(CONFIG_PPC32)	:= $(call cc-option, -ffixed-r2)
+
+# Clang doesn't support -mmultiple / -mno-multiple
+# https://llvm.org/pr39556
+CFLAGS-$(CONFIG_PPC32)	+= $(call cc-option, $(MULTIPLEWORD))
+
+CFLAGS-$(CONFIG_PPC32)	+= $(call cc-option,-mno-readonly-in-sdata)
+
+CC_FLAGS_FPU		:= $(call cc-option,-mhard-float)
+CC_FLAGS_NO_FPU		:= $(call cc-option,-msoft-float)
+
+ifdef CONFIG_FUNCTION_TRACER
+ifdef CONFIG_ARCH_USING_PATCHABLE_FUNCTION_ENTRY
+KBUILD_CPPFLAGS	+= -DCC_USING_PATCHABLE_FUNCTION_ENTRY
+ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
+CC_FLAGS_FTRACE := -fpatchable-function-entry=1
+else
+ifdef CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS # PPC32 only
+CC_FLAGS_FTRACE := -fpatchable-function-entry=3,1
+else
+CC_FLAGS_FTRACE := -fpatchable-function-entry=2
+endif
+endif
+else
+CC_FLAGS_FTRACE := -pg
+ifdef CONFIG_MPROFILE_KERNEL
+CC_FLAGS_FTRACE += -mprofile-kernel
+endif
+endif
+endif
+
+CFLAGS-$(CONFIG_TARGET_CPU_BOOL) += -mcpu=$(CONFIG_TARGET_CPU)
+AFLAGS-$(CONFIG_TARGET_CPU_BOOL) += -mcpu=$(CONFIG_TARGET_CPU)
+
+CFLAGS-y += $(CONFIG_TUNE_CPU)
+
+asinstr := $(call as-instr,lis 9$(comma)foo@high,-DHAVE_AS_ATHIGH=1)
+
+KBUILD_CPPFLAGS	+= -I $(srctree)/arch/powerpc $(asinstr)
+KBUILD_AFLAGS	+= $(AFLAGS-y)
+KBUILD_CFLAGS	+= $(CC_FLAGS_NO_FPU)
+KBUILD_CFLAGS	+= $(CFLAGS-y)
+
+CHECKFLAGS	+= -m$(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 prefix or pcrel
+ifdef CONFIG_PPC_KERNEL_PREFIXED
+KBUILD_CFLAGS += $(call cc-option,-mprefixed)
+else
+KBUILD_CFLAGS += $(call cc-option,-mno-prefixed)
+endif
+ifdef CONFIG_PPC_KERNEL_PCREL
+KBUILD_CFLAGS += $(call cc-option,-mpcrel)
+else
+KBUILD_CFLAGS += $(call cc-option,-mno-pcrel)
+endif
+
+# No AltiVec or VSX or MMA instructions when building kernel
+KBUILD_CFLAGS += $(call cc-option,-mno-altivec)
+KBUILD_CFLAGS += $(call cc-option,-mno-vsx)
+KBUILD_CFLAGS += $(call cc-option,-mno-mma)
+
+# 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)
+
+KBUILD_AFLAGS += $(aflags-y)
+KBUILD_CFLAGS += $(cflags-y)
+
+# Default to zImage, override when needed
+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) $(BOOT_TARGETS2)
+
+boot := arch/powerpc/boot
+
+$(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)/%,$@)
+
+include $(srctree)/scripts/Makefile.defconf
+
+generated_configs += ppc64le_defconfig
+ppc64le_defconfig:
+	$(call merge_into_defconfig,ppc64_defconfig,le)
+
+generated_configs += ppc64le_guest_defconfig
+ppc64le_guest_defconfig:
+	$(call merge_into_defconfig,ppc64_defconfig,le guest kvm_guest)
+
+generated_configs += ppc64_guest_defconfig
+ppc64_guest_defconfig:
+	$(call merge_into_defconfig,ppc64_defconfig,be guest kvm_guest)
+
+generated_configs += pseries_le_defconfig
+pseries_le_defconfig: ppc64le_guest_defconfig
+
+generated_configs += pseries_defconfig
+pseries_defconfig: ppc64le_guest_defconfig
+
+generated_configs += powernv_be_defconfig
+powernv_be_defconfig:
+	$(call merge_into_defconfig,powernv_defconfig,be)
+
+generated_configs += mpc85xx_defconfig
+mpc85xx_defconfig:
+	$(call merge_into_defconfig,mpc85xx_base.config,\
+		85xx-32bit 85xx-hw fsl-emb-nonhw)
+
+generated_configs += mpc85xx_smp_defconfig
+mpc85xx_smp_defconfig:
+	$(call merge_into_defconfig,mpc85xx_base.config,\
+		85xx-32bit 85xx-smp 85xx-hw fsl-emb-nonhw)
+
+generated_configs += corenet32_smp_defconfig
+corenet32_smp_defconfig:
+	$(call merge_into_defconfig,corenet_base.config,\
+		85xx-32bit 85xx-smp 85xx-hw fsl-emb-nonhw dpaa)
+
+generated_configs += corenet64_smp_defconfig
+corenet64_smp_defconfig:
+	$(call merge_into_defconfig,corenet_base.config,\
+		85xx-64bit 85xx-smp altivec 85xx-hw fsl-emb-nonhw dpaa)
+
+generated_configs += mpc86xx_defconfig
+mpc86xx_defconfig:
+	$(call merge_into_defconfig,mpc86xx_base.config,\
+		86xx-hw fsl-emb-nonhw)
+
+generated_configs += mpc86xx_smp_defconfig
+mpc86xx_smp_defconfig:
+	$(call merge_into_defconfig,mpc86xx_base.config,\
+		86xx-smp 86xx-hw fsl-emb-nonhw)
+
+generated_configs += ppc32_allmodconfig
+ppc32_allmodconfig:
+	$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/book3s_32.config \
+		-f $(srctree)/Makefile allmodconfig
+
+generated_configs += ppc44x_allmodconfig
+ppc44x_allmodconfig:
+	$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/44x.config \
+		-f $(srctree)/Makefile allmodconfig
+
+generated_configs += ppc8xx_allmodconfig
+ppc8xx_allmodconfig:
+	$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/8xx.config \
+		-f $(srctree)/Makefile allmodconfig
+
+generated_configs += ppc85xx_allmodconfig
+ppc85xx_allmodconfig:
+	$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/85xx-32bit.config \
+		-f $(srctree)/Makefile allmodconfig
+
+generated_configs += ppc_defconfig
+ppc_defconfig:
+	$(call merge_into_defconfig,book3s_32.config,)
+
+generated_configs += ppc64le_allmodconfig
+ppc64le_allmodconfig:
+	$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/le.config \
+		-f $(srctree)/Makefile allmodconfig
+
+generated_configs += ppc64le_allnoconfig
+ppc64le_allnoconfig:
+	$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/ppc64le.config \
+		-f $(srctree)/Makefile allnoconfig
+
+generated_configs += ppc64_book3e_allmodconfig
+ppc64_book3e_allmodconfig:
+	$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/85xx-64bit.config \
+		-f $(srctree)/Makefile allmodconfig
+
+generated_configs += ppc32_randconfig
+ppc32_randconfig:
+	$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/32-bit.config \
+		-f $(srctree)/Makefile randconfig
+
+generated_configs += ppc64_randconfig
+ppc64_randconfig:
+	$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/64-bit.config \
+		-f $(srctree)/Makefile randconfig
+
+PHONY += $(generated_configs)
+
+define archhelp
+  echo '* zImage          - Build default images selected by kernel config'
+  echo '  zImage.*        - Compressed kernel image (arch/powerpc/boot/zImage.*)'
+  echo '  uImage          - U-Boot native image format'
+  echo '  cuImage.<dt>    - Backwards compatible U-Boot image for older'
+  echo '                    versions which do not support device trees'
+  echo '  dtbImage.<dt>   - zImage with an embedded device tree blob'
+  echo '  simpleImage.<dt> - Firmware independent image.'
+  echo '  treeImage.<dt>  - Support for older IBM 4xx firmware (not U-Boot)'
+  echo '  install         - Install kernel using'
+  echo '                    (your) ~/bin/$(INSTALLKERNEL) or'
+  echo '                    (distribution) /sbin/$(INSTALLKERNEL) or'
+  echo '                    install to $$(INSTALL_PATH)'
+  echo '  *_defconfig     - Select default config from arch/powerpc/configs'
+  echo ''
+  echo '  Targets with <dt> embed a device tree blob inside the image'
+  echo '  These targets support board with firmware that does not'
+  echo '  support passing a device tree directly.  Replace <dt> with the'
+  echo '  name of a dts file from the arch/powerpc/boot/dts/ directory'
+  echo '  (minus the .dts extension).'
+  echo
+  $(foreach cfg,$(generated_configs),
+    printf "  %-27s - Build for %s\\n" $(cfg) $(subst _defconfig,,$(cfg));)
+endef
+
+PHONY += install
+install:
+	$(call cmd,install)
+
+ifeq ($(KBUILD_EXTMOD),)
+# We need to generate vdso-offsets.h before compiling certain files in kernel/.
+# In order to do that, we should use the archprepare target, but we can't since
+# asm-offsets.h is included in some files used to generate vdso-offsets.h, and
+# asm-offsets.h is built in prepare0, for which archprepare is a dependency.
+# Therefore we need to generate the header after prepare0 has been made, hence
+# this hack.
+prepare: vdso_prepare
+vdso_prepare: prepare0
+	$(if $(CONFIG_VDSO32),$(Q)$(MAKE) \
+		$(build)=arch/powerpc/kernel/vdso include/generated/vdso32-offsets.h)
+	$(if $(CONFIG_PPC64),$(Q)$(MAKE) \
+		$(build)=arch/powerpc/kernel/vdso include/generated/vdso64-offsets.h)
+endif
+
+archprepare: checkbin
+
+archheaders:
+	$(Q)$(MAKE) $(build)=arch/powerpc/kernel/syscalls all
+
+ifdef CONFIG_STACKPROTECTOR
+prepare: stack_protector_prepare
+
+PHONY += stack_protector_prepare
+stack_protector_prepare: prepare0
+ifdef CONFIG_PPC64
+	$(eval KBUILD_CFLAGS += -mstack-protector-guard=tls -mstack-protector-guard-reg=r13 \
+				-mstack-protector-guard-offset=$(shell awk '{if ($$2 == "PACA_CANARY") print $$3;}' \
+				$(objtree)/include/generated/asm-offsets.h))
+else
+	$(eval KBUILD_CFLAGS += -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 \
+				-mstack-protector-guard-offset=$(shell awk '{if ($$2 == "TASK_CANARY") print $$3;}' \
+				$(objtree)/include/generated/asm-offsets.h))
+endif
+endif
+
+PHONY += checkbin
+checkbin:
+	@if test "x${CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT}" = "xy" -a \
+		"x${CONFIG_LD_IS_BFD}" = "xy" -a \
+		"${CONFIG_LD_VERSION}" = "23700" ; then \
+		echo -n '*** binutils 2.37 drops unused section symbols, which recordmcount ' ; \
+		echo 'is unable to handle.' ; \
+		echo '*** Please use a different binutils version.' ; \
+		false ; \
+	fi