xref: /netbsd-src/lib/libc/arch/x86_64/sys/__sigtramp2.S (revision 28928a88a35ff65d3276b94867a479f589b3bce2)
1/*	$NetBSD: __sigtramp2.S,v 1.9 2020/10/19 11:29:26 kamil Exp $	*/
2
3/*
4 * Copyright (c) 2001 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Frank van der Linden for Wasabi Systems, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *      This product includes software developed for the NetBSD Project by
20 *      Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 *    or promote products derived from this software without specific prior
23 *    written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38#include "SYS.h"
39#include "assym.h"
40
41/*
42 * The x86-64 signal trampoline is invoked only to return from
43 * the signal; the kernel calls the signal handler directly.
44 *
45 * The unwind entry includes the one byte prior to the trampoline
46 * because the unwinder will look up (return PC - 1) while unwinding.
47 * Normally (return PC - 1) computes an address inside the call
48 * instruction that created the child frame, but here there is no call
49 * instruction so we have to manually add padding.
50 */
51	.cfi_startproc simple
52	.cfi_signal_frame
53	.cfi_def_cfa r15, 0
54	.cfi_offset rax, UC_GREGS_RAX
55	.cfi_offset rdx, UC_GREGS_RDX
56	.cfi_offset rcx, UC_GREGS_RCX
57	.cfi_offset rbx, UC_GREGS_RBX
58	.cfi_offset rsi, UC_GREGS_RSI
59	.cfi_offset rdi, UC_GREGS_RDI
60	.cfi_offset rbp, UC_GREGS_RBP
61	.cfi_offset rsp, UC_GREGS_RSP
62	.cfi_offset r8,  UC_GREGS_R8
63	.cfi_offset r9,  UC_GREGS_R9
64	.cfi_offset r10, UC_GREGS_R10
65	.cfi_offset r11, UC_GREGS_R11
66	.cfi_offset r12, UC_GREGS_R12
67	.cfi_offset r13, UC_GREGS_R13
68	.cfi_offset r14, UC_GREGS_R14
69	.cfi_offset r15, UC_GREGS_R15
70	.cfi_offset rip, UC_GREGS_RIP
71	nop
72NENTRY(__sigtramp_siginfo_2)
73	movq	%r15,%rdi
74	movq	$SYS_setcontext, %rax
75	syscall
76	movq	$-1,%rdi /* if we return here, something is wrong */
77	movq	$SYS_exit, %rax
78	syscall
79	.cfi_endproc
80END(__sigtramp_siginfo_2)
81