Merge tag 'metag-for-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan...

[cascardo/linux.git] / arch / s390 / kernel / kprobes.c

diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c
index 250f597..dd6306c 100644 (file)
--- a/arch/s390/kernel/kprobes.c
+++ b/arch/s390/kernel/kprobes.c
@@ -690,6 +690,15 @@ int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
        stack = (unsigned long) regs->gprs[15];
 
        memcpy(kcb->jprobes_stack, (void *) stack, MIN_STACK_SIZE(stack));
+
+       /*
+        * jprobes use jprobe_return() which skips the normal return
+        * path of the function, and this messes up the accounting of the
+        * function graph tracer to get messed up.
+        *
+        * Pause function graph tracing while performing the jprobe function.
+        */
+       pause_graph_tracing();
        return 1;
 }
 NOKPROBE_SYMBOL(setjmp_pre_handler);
@@ -705,6 +714,9 @@ int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
        struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
        unsigned long stack;
 
+       /* It's OK to start function graph tracing again */
+       unpause_graph_tracing();
+
        stack = (unsigned long) kcb->jprobe_saved_regs.gprs[15];
 
        /* Put the regs back */