arch/tile: apply commit 74fca9da to the compat signal handling as well

commit a134d228 upstream.

This passes siginfo and mcontext to tilegx32 signal handlers that
don't have SA_SIGINFO set just as we have been doing for tilegx64.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

arch/tile/kernel/compat_signal.c

@@ -406,19 +406,17 @@ int compat_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 	 * Set up registers for signal handler.
 	 * Registers that we don't modify keep the value they had from
 	 * user-space at the time we took the signal.
+	 * We always pass siginfo and mcontext, regardless of SA_SIGINFO,
+	 * since some things rely on this (e.g. glibc's debug/segfault.c).
 	 */
 	regs->pc = ptr_to_compat_reg(ka->sa.sa_handler);
 	regs->ex1 = PL_ICS_EX1(USER_PL, 1); /* set crit sec in handler */
 	regs->sp = ptr_to_compat_reg(frame);
 	regs->lr = restorer;
 	regs->regs[0] = (unsigned long) usig;
-
-	if (ka->sa.sa_flags & SA_SIGINFO) {
-		/* Need extra arguments, so mark to restore caller-saves. */
-		regs->regs[1] = ptr_to_compat_reg(&frame->info);
-		regs->regs[2] = ptr_to_compat_reg(&frame->uc);
-		regs->flags |= PT_FLAGS_CALLER_SAVES;
-	}
+	regs->regs[1] = ptr_to_compat_reg(&frame->info);
+	regs->regs[2] = ptr_to_compat_reg(&frame->uc);
+	regs->flags |= PT_FLAGS_CALLER_SAVES;
 
 	/*
 	 * Notify any tracer that was single-stepping it.