um: let signal_delivered() do SIGTRAP on singlestepping into handler

... rather than duplicating that in sigframe setup code (and doing that
inconsistently, at that)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 5 insertions, 1 deletions

diff --git a/arch/um/kernel/signal.c b/arch/um/kernel/signal.c
index 7362d58efc29..cc9c2350e417 100644
--- a/arch/um/kernel/signal.c
+++ b/arch/um/kernel/signal.c
@@ -22,9 +22,13 @@ static void handle_signal(struct pt_regs *regs, unsigned long signr,
                          struct k_sigaction *ka, siginfo_t *info)
 {
         sigset_t *oldset = sigmask_to_save();
+        int singlestep = 0;
         unsigned long sp;
         int err;
 
+        if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
+                singlestep = 1;
+
         /* Did we come from a system call? */
         if (PT_REGS_SYSCALL_NR(regs) >= 0) {
                 /* If so, check system call restarting.. */
@@ -61,7 +65,7 @@ static void handle_signal(struct pt_regs *regs, unsigned long signr,
         if (err)
                 force_sigsegv(signr, current);
         else
-                signal_delivered(signr, info, ka, regs, 0);
+                signal_delivered(signr, info, ka, regs, singlestep);
 }
 
 static int kern_do_signal(struct pt_regs *regs)