At Sat, 21 Feb 2015 09:51:23 +0000,
Al Viro wrote:

On Sat, Feb 21, 2015 at 04:53:49PM +0900, Yoshinori Sato wrote:

quoted

+static inline void *
+get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
+{
+	unsigned long usp;
+
+	/* Default to using normal stack.  */
+	usp = rdusp();
+
+	/* This is the X/Open sanctioned signal stack switching.  */
+	if (ka->sa.sa_flags & SA_ONSTACK) {
+		if (!sas_ss_flags(usp))
+			usp = current->sas_ss_sp + current->sas_ss_size;
+	}

Use sigsp(), please.  Pass ksig to that sucker and it'll become
	return (void *)((sigsp(rdusp, ksig) - frame_size) & -8UL);

OK.

quoted

+static void do_signal(struct pt_regs *regs)
+	 * We want the common case to go fast, which
+	 * is why we may in certain cases get here from
+	 * kernel mode. Just return without doing anything
+	 * if so.
+	 */
+	if ((regs->ccr & 0x10))
+		return;

Can we get there in kernel mode, actually?

It case checking for entry.S
Removed.

Thanks.

-- 
Yoshinori Sato
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