Commit aaa4dd1b authored by Wang Kefeng's avatar Wang Kefeng Committed by Russell King (Oracle)
Browse files

ARM: 9279/1: support function error injection 



This enables HAVE_FUNCTION_ERROR_INJECTION by adding necessary
regs_set_return_value() and override_function_with_return().

Simply tested according to Documentation/fault-injection/fault-injection.rst.

Signed-off-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: default avatarRussell King (Oracle) <rmk+kernel@armlinux.org.uk>
parent ba290d4f

arch/arm/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -97,6 +97,7 @@ config ARM 
	select HAVE_EXIT_THREAD

	select HAVE_FAST_GUP if ARM_LPAE

	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL

	select HAVE_FUNCTION_ERROR_INJECTION

	select HAVE_FUNCTION_GRAPH_TRACER

	select HAVE_FUNCTION_TRACER if !XIP_KERNEL

	select HAVE_GCC_PLUGINS

arch/arm/include/asm/ptrace.h

+4 −0
Original line number Diff line number Diff line
@@ -163,6 +163,10 @@ static inline unsigned long user_stack_pointer(struct pt_regs *regs) 
		((current_stack_pointer | (THREAD_SIZE - 1)) - 7) - 1;	\

})



static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc)

{

	regs->ARM_r0 = rc;

}



/*

 * Update ITSTATE after normal execution of an IT block instruction.

arch/arm/lib/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -44,3 +44,5 @@ ifeq ($(CONFIG_KERNEL_MODE_NEON),y) 
  CFLAGS_xor-neon.o		+= $(NEON_FLAGS)

  obj-$(CONFIG_XOR_BLOCKS)	+= xor-neon.o

endif



obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o

arch/arm/lib/error-inject.c

0 → 100644
+10 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0



#include <linux/error-injection.h>

#include <linux/kprobes.h>



void override_function_with_return(struct pt_regs *regs)

{

	instruction_pointer_set(regs, regs->ARM_lr);

}

NOKPROBE_SYMBOL(override_function_with_return);