X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;ds=sidebyside;f=include%2Fasm-i386%2Fptrace.h;h=7e0f2945d17d48587dadf5a6b6b5d027b9869b0a;hb=24c83d45d76303db8325b8553a05c69c838ef370;hp=eef9f93870d4b103d7f8104d540e5227f883a61e;hpb=54522b6613a03807f057fd567794a31267ef85cb;p=linux-2.6

diff --git a/include/asm-i386/ptrace.h b/include/asm-i386/ptrace.h
index eef9f93870..7e0f2945d1 100644
--- a/include/asm-i386/ptrace.h
+++ b/include/asm-i386/ptrace.h
@@ -55,16 +55,33 @@ struct pt_regs {
 #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);
-#define user_mode(regs)		(3 & (regs)->xcs)
-#define user_mode_vm(regs)	((VM_MASK & (regs)->eflags) || user_mode(regs))
+
+/*
+ * 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
+#endif /* __KERNEL__ */
 
 #endif