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linux/include/asm-i386/ptrace.h
Zachary Amsden 0998e4228a [PATCH] x86: privilege cleanup
Privilege checking cleanup.  Originally, these diffs were much greater, but
recent cleanups in Linux have already done much of the cleanup.  I added
some explanatory comments in places where the reasoning behind certain
tests is rather subtle.

Also, in traps.c, we can skip the user_mode check in handle_BUG().  The
reason is, there are only two call chains - one via die_if_kernel() and one
via do_page_fault(), both entering from die().  Both of these paths already
ensure that a kernel mode failure has happened.  Also, the original check
here, if (user_mode(regs)) was insufficient anyways, since it would not
rule out BUG faults from V8086 mode execution.

Saving the %ss segment in show_regs() rather than assuming a fixed value
also gives better information about the current kernel state in the
register dump.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:12 -07:00

88 lines
2.0 KiB
C

#ifndef _I386_PTRACE_H
#define _I386_PTRACE_H
#define EBX 0
#define ECX 1
#define EDX 2
#define ESI 3
#define EDI 4
#define EBP 5
#define EAX 6
#define DS 7
#define ES 8
#define FS 9
#define GS 10
#define ORIG_EAX 11
#define EIP 12
#define CS 13
#define EFL 14
#define UESP 15
#define SS 16
#define FRAME_SIZE 17
/* this struct defines the way the registers are stored on the
stack during a system call. */
struct pt_regs {
long ebx;
long ecx;
long edx;
long esi;
long edi;
long ebp;
long eax;
int xds;
int xes;
long orig_eax;
long eip;
int xcs;
long eflags;
long esp;
int xss;
};
/* Arbitrarily choose the same ptrace numbers as used by the Sparc code. */
#define PTRACE_GETREGS 12
#define PTRACE_SETREGS 13
#define PTRACE_GETFPREGS 14
#define PTRACE_SETFPREGS 15
#define PTRACE_GETFPXREGS 18
#define PTRACE_SETFPXREGS 19
#define PTRACE_OLDSETOPTIONS 21
#define PTRACE_GET_THREAD_AREA 25
#define PTRACE_SET_THREAD_AREA 26
#ifdef __KERNEL__
#include <asm/vm86.h>
struct task_struct;
extern void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code);
/*
* user_mode_vm(regs) determines whether a register set came from user mode.
* This is true if V8086 mode was enabled OR if the register set was from
* protected mode with RPL-3 CS value. This tricky test checks that with
* one comparison. Many places in the kernel can bypass this full check
* if they have already ruled out V8086 mode, so user_mode(regs) can be used.
*/
static inline int user_mode(struct pt_regs *regs)
{
return (regs->xcs & 3) != 0;
}
static inline int user_mode_vm(struct pt_regs *regs)
{
return ((regs->xcs & 3) | (regs->eflags & VM_MASK)) != 0;
}
#define instruction_pointer(regs) ((regs)->eip)
#if defined(CONFIG_SMP) && defined(CONFIG_FRAME_POINTER)
extern unsigned long profile_pc(struct pt_regs *regs);
#else
#define profile_pc(regs) instruction_pointer(regs)
#endif
#endif /* __KERNEL__ */
#endif