1/* $NetBSD: __sigtramp2.S,v 1.7 2020/10/19 11:31:01 kamil Exp $ */ 2 3/*- 4 * Copyright (c) 2002 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Christos Zoulas. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32#include "SYS.h" 33#include "assym.h" 34 35/* 36 * The i386 signal trampoline is invoked only to return from 37 * the signal; the kernel calls the signal handler directly. 38 * 39 * On entry, stack looks like: 40 * 41 * ucontext structure [12+sizeof(siginfo_t)] 42 * siginfo structure [12] 43 * pointer to ucontext structure [8] 44 * pointer to siginfo structure [4] 45 * sp-> signal number [0] 46 * 47 * The unwind entry includes the one byte prior to the trampoline 48 * because the unwinder will look up (return PC - 1) while unwinding. 49 * Normally (return PC - 1) computes an address inside the call 50 * instruction that created the child frame, but here there is no call 51 * instruction so we have to manually add padding. 52 */ 53 .cfi_startproc simple 54 .cfi_signal_frame 55 .cfi_def_cfa esp, 140 56 .cfi_offset eax, UC_GREGS_EAX 57 .cfi_offset ecx, UC_GREGS_ECX 58 .cfi_offset edx, UC_GREGS_EDX 59 .cfi_offset ebx, UC_GREGS_EBX 60 .cfi_offset esp, UC_GREGS_ESP 61 .cfi_offset ebp, UC_GREGS_EBP 62 .cfi_offset esi, UC_GREGS_ESI 63 .cfi_offset edi, UC_GREGS_EDI 64 .cfi_offset eip, UC_GREGS_EIP 65 nop 66NENTRY(__sigtramp_siginfo_2) 67 leal 12+128(%esp),%eax /* get address of ucontext */ 68 movl %eax,4(%esp) /* put it in the argument slot */ 69 /* fake return address already there */ 70 SYSTRAP(setcontext) /* do setcontext */ 71 movl $-1,4(%esp) /* if we return here, something is wrong */ 72 SYSTRAP(exit) /* exit */ 73 .cfi_endproc 74END(__sigtramp_siginfo_2) 75