exit: Add and use make_task_dead.

There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

2 files changed, 2 insertions, 6 deletions

diff --git a/arch/sparc/kernel/traps_32.c b/arch/sparc/kernel/traps_32.c
index 5630e5a395e0..179aabfa712e 100644
--- a/arch/sparc/kernel/traps_32.c
+++ b/arch/sparc/kernel/traps_32.c
@@ -86,9 +86,7 @@ void __noreturn die_if_kernel(char *str, struct pt_regs *regs)
 	}
 	printk("Instruction DUMP:");
 	instruction_dump ((unsigned long *) regs->pc);
-	if(regs->psr & PSR_PS)
-		do_exit(SIGKILL);
-	do_exit(SIGSEGV);
+	make_task_dead((regs->psr & PSR_PS) ? SIGKILL : SIGSEGV);
 }
 
 void do_hw_interrupt(struct pt_regs *regs, unsigned long type)
diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c
index 6863025ed56d..21077821f427 100644
--- a/arch/sparc/kernel/traps_64.c
+++ b/arch/sparc/kernel/traps_64.c
@@ -2559,9 +2559,7 @@ void __noreturn die_if_kernel(char *str, struct pt_regs *regs)
 	}
 	if (panic_on_oops)
 		panic("Fatal exception");
-	if (regs->tstate & TSTATE_PRIV)
-		do_exit(SIGKILL);
-	do_exit(SIGSEGV);
+	make_task_dead((regs->tstate & TSTATE_PRIV)? SIGKILL : SIGSEGV);
 }
 EXPORT_SYMBOL(die_if_kernel);