From: Russell King <rmk@dyn-67.arm.linux.org.uk>
Date: Sat, 24 Jun 2006 21:41:09 +0000 (+0100)
Subject: [ARM] Add identifying number for non-rt sigframe
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=ca195cfec9fff622a61b1b72534e73360747f735;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

[ARM] Add identifying number for non-rt sigframe

GDB couldn't reliably tell the difference between the old and new
non-rt sigframes, so provide it with a number at the beginning which
will never appear in the old sigframe, and hence provide gdb with a
reliable way to tell the two apart.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---

diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index 962851144099..c0ba8afee42f 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -470,6 +470,11 @@ setup_frame(int usig, struct k_sigaction *ka, sigset_t *set, struct pt_regs *reg
 	if (!frame)
 		return 1;
 
+	/*
+	 * Set uc.uc_flags to a value which sc.trap_no would never have.
+	 */
+	__put_user_error(0x5ac3c35a, &frame->uc.uc_flags, err);
+
 	err |= setup_sigframe(frame, regs, set);
 	if (err == 0)
 		err = setup_return(regs, ka, frame->retcode, frame, usig);