[S390] add breaking event address for user space
Copy the last breaking event address from the lowcore to a new
field in the thread_struct on each system entry. Add a new
ptrace request PTRACE_GET_LAST_BREAK and a new utrace regset
REGSET_LAST_BREAK to query the last breaking event.
This is useful for debugging wild branches in user space code.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
index 44a4336..d9b490a 100644
--- a/arch/s390/kernel/asm-offsets.c
+++ b/arch/s390/kernel/asm-offsets.c
@@ -39,6 +39,7 @@
DEFINE(__TI_precount, offsetof(struct thread_info, preempt_count));
DEFINE(__TI_user_timer, offsetof(struct thread_info, user_timer));
DEFINE(__TI_system_timer, offsetof(struct thread_info, system_timer));
+ DEFINE(__TI_last_break, offsetof(struct thread_info, last_break));
BLANK();
DEFINE(__PT_ARGS, offsetof(struct pt_regs, args));
DEFINE(__PT_PSW, offsetof(struct pt_regs, psw));