nommu: ptrace support (68b7f715) · Commits · 戴 / test

The patch below adds ARM ptrace functions to get the process load address. This is required for useful userspace debugging on mmuless systems. These values are obtained by reading magic offsets with PTRACE_PEEKUSR, as on other nommu targets. I picked arbitrary large values for the offsets. Signed-off-by:

Paul Brook <paul@codesourcery.com>

arch/arm/include/asm/ptrace.h

+8 −0

Original line number	Diff line number	Diff line
		@@ -82,6 +82,14 @@
		#define PSR_ENDSTATE 0
		#endif

		/*
		* These are 'magic' values for PTRACE_PEEKUSR that return info about where a
		* process is located in memory.
		*/
		#define PT_TEXT_ADDR 0x10000
		#define PT_DATA_ADDR 0x10004
		#define PT_TEXT_END_ADDR 0x10008

		#ifndef __ASSEMBLY__

		/*

arch/arm/kernel/ptrace.c

+7 −1

Original line number	Diff line number	Diff line
		@@ -521,7 +521,13 @@ static int ptrace_read_user(struct task_struct *tsk, unsigned long off,
		return -EIO;

		tmp = 0;
		if (off < sizeof(struct pt_regs))
		if (off == PT_TEXT_ADDR)
		tmp = tsk->mm->start_code;
		else if (off == PT_DATA_ADDR)
		tmp = tsk->mm->start_data;
		else if (off == PT_TEXT_END_ADDR)
		tmp = tsk->mm->end_code;
		else if (off < sizeof(struct pt_regs))
		tmp = get_user_reg(tsk, off >> 2);

		return put_user(tmp, ret);

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