freebsd-dev/sys/amd64/ia32/ia32_exception.S
Konstantin Belousov b3a7db3b06 Use SMAP on amd64.
Ifuncs selectors dispatch copyin(9) family to the suitable variant, to
set rflags.AC around userspace access.  Rflags.AC bit is cleared in
all kernel entry points unconditionally even on machines not
supporting SMAP.

Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D13838
2018-07-29 20:47:00 +00:00

81 lines
2.6 KiB
ArmAsm

/*-
* Copyright (c) 2003 Peter Wemm
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <machine/asmacros.h>
#include "assym.inc"
.text
/*
* Call gate entry for FreeBSD ELF and Linux/NetBSD syscall (int 0x80)
*
* This is a SDT_SYSIDT entry point (unlike the i386 port) so that we
* can do a swapgs before enabling interrupts. This is critical because
* if we took an interrupt before swapgs, the interrupt code would see
* that it originated in supervisor mode and skip the swapgs.
*/
SUPERALIGN_TEXT
IDTVEC(int0x80_syscall_pti)
PTI_UENTRY has_err=0
jmp int0x80_syscall_common
SUPERALIGN_TEXT
IDTVEC(int0x80_syscall)
swapgs
int0x80_syscall_common:
pushq $2 /* sizeof "int 0x80" */
subq $TF_ERR,%rsp /* skip over tf_trapno */
movq %rdi,TF_RDI(%rsp)
movq PCPU(CURPCB),%rdi
andl $~PCB_FULL_IRET,PCB_FLAGS(%rdi)
SAVE_SEGS
movq %rax,TF_RAX(%rsp)
movq %rdx,TF_RDX(%rsp)
movq %rcx,TF_RCX(%rsp)
call handle_ibrs_entry
sti
movq %rsi,TF_RSI(%rsp)
movq %r8,TF_R8(%rsp)
movq %r9,TF_R9(%rsp)
movq %rbx,TF_RBX(%rsp)
movq %rbp,TF_RBP(%rsp)
movq %r10,TF_R10(%rsp)
movq %r11,TF_R11(%rsp)
movq %r12,TF_R12(%rsp)
movq %r13,TF_R13(%rsp)
movq %r14,TF_R14(%rsp)
movq %r15,TF_R15(%rsp)
movl $TF_HASSEGS,TF_FLAGS(%rsp)
pushfq
andq $~(PSL_D | PSL_AC),(%rsp)
popfq
FAKE_MCOUNT(TF_RIP(%rsp))
movq %rsp, %rdi
call ia32_syscall
MEXITCOUNT
jmp doreti