s390/traps: Change stack overflow message

When the kernel stack pointer is pointing to invalid memory,
a 'Kernel stack overflow' message is printed, which is misleading.
Change the message to actually say that the stack pointer is invalid
instead.

Reviewed-by: Heiko Carstens <[e-mail]>
Signed-off-by: Sven Schnelle <[e-mail]>
Signed-off-by: Vasily Gorbik <[e-mail]>

arch/s390/kernel/entry.S

···
 	clg	%r14,__LC_RESTART_STACK(\lowcore)
 	je	\oklabel
 	la	%r14,\savearea(\lowcore)
-	j	stack_overflow
+	j	stack_invalid
 	.endm
 
 	/*
···
 	tm	__LC_PGM_ILC+3(%r13),0x80	# check for per exception
 	jnz	.Lpgm_svcper		# -> single stepped svc
 2:	aghi	%r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
-	# CHECK_VMAP_STACK branches to stack_overflow or 4f
+	# CHECK_VMAP_STACK branches to stack_invalid or 4f
 	CHECK_VMAP_STACK __LC_SAVE_AREA,%r13,4f
 3:	lg	%r15,__LC_KERNEL_STACK(%r13)
 4:	la	%r11,STACK_FRAME_OVERHEAD(%r15)
···
 	.section .kprobes.text, "ax"
 
 /*
- * The synchronous or the asynchronous stack overflowed. We are dead.
+ * The synchronous or the asynchronous stack pointer is invalid. We are dead.
  * No need to properly save the registers, we are going to panic anyway.
  * Setup a pt_regs so that show_trace can provide a good call trace.
  */
-SYM_CODE_START(stack_overflow)
+SYM_CODE_START(stack_invalid)
 	GET_LC	%r15
 	lg	%r15,__LC_NODAT_STACK(%r15) # change to panic stack
 	la	%r11,STACK_FRAME_OVERHEAD(%r15)
···
 	stg	%r10,__PT_ORIG_GPR2(%r11) # store last break to orig_gpr2
 	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
 	lgr	%r2,%r11		# pass pointer to pt_regs
-	jg	kernel_stack_overflow
-SYM_CODE_END(stack_overflow)
+	jg	kernel_stack_invalid
+SYM_CODE_END(stack_invalid)
 
 	.section .data, "aw"
 	.balign	4

arch/s390/kernel/entry.h

···
 void do_non_secure_storage_access(struct pt_regs *regs);
 void do_secure_storage_violation(struct pt_regs *regs);
 void do_report_trap(struct pt_regs *regs, int si_signo, int si_code, char *str);
-void kernel_stack_overflow(struct pt_regs * regs);
+void kernel_stack_invalid(struct pt_regs *regs);
 void handle_signal32(struct ksignal *ksig, sigset_t *oldset,
 		     struct pt_regs *regs);
 

arch/s390/kernel/traps.c

···
 	}
 }
 
-void kernel_stack_overflow(struct pt_regs *regs)
+void kernel_stack_invalid(struct pt_regs *regs)
 {
 	/*
 	 * Normally regs are unpoisoned by the generic entry code, but
···
 	 */
 	kmsan_unpoison_entry_regs(regs);
 	bust_spinlocks(1);
-	pr_emerg("Kernel stack overflow\n");
+	pr_emerg("Kernel stack pointer invalid\n");
 	show_regs(regs);
 	bust_spinlocks(0);
-	panic("Corrupt kernel stack, cannot continue");
+	panic("Invalid kernel stack pointer, cannot continue");
 }
-NOKPROBE_SYMBOL(kernel_stack_overflow);
+NOKPROBE_SYMBOL(kernel_stack_invalid);
 
 static void __init test_monitor_call(void)
 {