The call chain is: breakpoint notify_die hw_breakpoint_exceptions_notify hw_breakpoint_handler So the signal number can only be SIGTRAP. In hw_breakpoint_handler rc is either NOTIFY_STOP or NOTIF_DONE both of which notifier_to_errno converts to 0. So si_errno is 0. Historically si_addr was left unitialized in struct siginfo which is a bug. There appears to be no consensus among the various architectures which value should be in si_addr. So since no usable value has been returned up to this point return NULL in si_addr. Fixes: 4352fc1b12fa ("sh: Abstracted SH-4A UBC support on hw-breakpoint core.") Fixes: 34d0b5af50a0 ("sh: Convert ptrace to hw_breakpoint API.") Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: Paul Mundt <lethal@xxxxxxxxxxxx> Cc: linux-sh@xxxxxxxxxxxxxxx Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> --- arch/sh/kernel/hw_breakpoint.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/arch/sh/kernel/hw_breakpoint.c b/arch/sh/kernel/hw_breakpoint.c index afe965712a69..8648ed05ccf0 100644 --- a/arch/sh/kernel/hw_breakpoint.c +++ b/arch/sh/kernel/hw_breakpoint.c @@ -347,13 +347,8 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args) /* Deliver the signal to userspace */ if (!arch_check_bp_in_kernelspace(bp)) { - siginfo_t info; - - info.si_signo = args->signr; - info.si_errno = notifier_to_errno(rc); - info.si_code = TRAP_HWBKPT; - - force_sig_info(args->signr, &info, current); + force_sig_fault(SIGTRAP, TRAP_HWBKPT, + (void __user *)NULL, current); } rcu_read_unlock(); -- 2.14.1