Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

Pull ARM updates from Russell King:
 "Updates for IRQ stacks and virtually mapped stack support, and ftrace:

   - Support for IRQ and vmap'ed stacks

     This covers all the work related to implementing IRQ stacks and
     vmap'ed stacks for all 32-bit ARM systems that are currently
     supported by the Linux kernel, including RiscPC and Footbridge. It
     has been submitted for review in four different waves:

      - IRQ stacks support for v7 SMP systems [0]

      - vmap'ed stacks support for v7 SMP systems[1]

      - extending support for both IRQ stacks and vmap'ed stacks for all
        remaining configurations, including v6/v7 SMP multiplatform
        kernels and uniprocessor configurations including v7-M [2]

      - fixes and updates in [3]

   - ftrace fixes and cleanups

     Make all flavors of ftrace available on all builds, regardless of
     ISA choice, unwinder choice or compiler [4]:

      - use ADD not POP where possible

      - fix a couple of Thumb2 related issues

      - enable HAVE_FUNCTION_GRAPH_FP_TEST for robustness

      - enable the graph tracer with the EABI unwinder

      - avoid clobbering frame pointer registers to make Clang happy

   - Fixes for the above"

[0] https://lore.kernel.org/linux-arm-kernel/20211115084732.3704393-1-ardb@kernel.org/
[1] https://lore.kernel.org/linux-arm-kernel/20211122092816.2865873-1-ardb@kernel.org/
[2] https://lore.kernel.org/linux-arm-kernel/20211206164659.1495084-1-ardb@kernel.org/
[3] https://lore.kernel.org/linux-arm-kernel/20220124174744.1054712-1-ardb@kernel.org/
[4] https://lore.kernel.org/linux-arm-kernel/20220203082204.1176734-1-ardb@kernel.org/

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (62 commits)
  ARM: fix building NOMMU ARMv4/v5 kernels
  ARM: unwind: only permit stack switch when unwinding call_with_stack()
  ARM: Revert "unwind: dump exception stack from calling frame"
  ARM: entry: fix unwinder problems caused by IRQ stacks
  ARM: unwind: set frame.pc correctly for current-thread unwinding
  ARM: 9184/1: return_address: disable again for CONFIG_ARM_UNWIND=y
  ARM: 9183/1: unwind: avoid spurious warnings on bogus code addresses
  Revert "ARM: 9144/1: forbid ftrace with clang and thumb2_kernel"
  ARM: mach-bcm: disable ftrace in SMC invocation routines
  ARM: cacheflush: avoid clobbering the frame pointer
  ARM: kprobes: treat R7 as the frame pointer register in Thumb2 builds
  ARM: ftrace: enable the graph tracer with the EABI unwinder
  ARM: unwind: track location of LR value in stack frame
  ARM: ftrace: enable HAVE_FUNCTION_GRAPH_FP_TEST
  ARM: ftrace: avoid unnecessary literal loads
  ARM: ftrace: avoid redundant loads or clobbering IP
  ARM: ftrace: use trampolines to keep .init.text in branching range
  ARM: ftrace: use ADD not POP to counter PUSH at entry
  ARM: ftrace: ensure that ADR takes the Thumb bit into account
  ARM: make get_current() and __my_cpu_offset() __always_inline
  ...

2 files changed, 1 insertions, 12 deletions

diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
index 954eee8a785a..187a187706cb 100644
--- a/arch/arm/boot/compressed/Makefile
+++ b/arch/arm/boot/compressed/Makefile
@@ -92,17 +92,13 @@ ifeq ($(CONFIG_USE_OF),y)
 OBJS	+= $(libfdt_objs) fdt_check_mem_start.o
 endif
 
-# -fstack-protector-strong triggers protection checks in this code,
-# but it is being used too early to link to meaningful stack_chk logic.
-$(foreach o, $(libfdt_objs) atags_to_fdt.o fdt_check_mem_start.o, \
-	$(eval CFLAGS_$(o) := -I $(srctree)/scripts/dtc/libfdt -fno-stack-protector))
-
 targets       := vmlinux vmlinux.lds piggy_data piggy.o \
 		 head.o $(OBJS)
 
 KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
 
 ccflags-y := -fpic $(call cc-option,-mno-single-pic-base,) -fno-builtin \
+	     -I$(srctree)/scripts/dtc/libfdt -fno-stack-protector \
 	     -I$(obj) $(DISABLE_ARM_SSP_PER_TASK_PLUGIN)
 ccflags-remove-$(CONFIG_FUNCTION_TRACER) += -pg
 asflags-y := -DZIMAGE
diff --git a/arch/arm/boot/compressed/misc.c b/arch/arm/boot/compressed/misc.c
index e1e9a5dde853..c3c66ff2d696 100644
--- a/arch/arm/boot/compressed/misc.c
+++ b/arch/arm/boot/compressed/misc.c
@@ -128,13 +128,6 @@ asmlinkage void __div0(void)
 	error("Attempting division by 0!");
 }
 
-const unsigned long __stack_chk_guard = 0x000a0dff;
-
-void __stack_chk_fail(void)
-{
-	error("stack-protector: Kernel stack is corrupted\n");
-}
-
 extern int do_decompress(u8 *input, int len, u8 *output, void (*error)(char *x));