freebsd-dev/sys/i386/isa/ipl.s
Bruce Evans f318190a01 Fixed checking for VM86 mode in doreti which I broke in rev.1.30. Only
the case of VM86 calls from the kernel was broken, so this bug was not
a security hole.

PR:		36710
Submitted by:	David Xu <davidx@viasoft.com.cn> (version for RELENG_4)
MFC after:	3 days
2002-05-05 03:19:48 +00:00

146 lines
4.3 KiB
ArmAsm

/*-
* Copyright (c) 1989, 1990 William F. Jolitz.
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* @(#)ipl.s
*
* $FreeBSD$
*/
/*
* AT/386
* Vector interrupt control section
*/
.text
/*
* void doreti(struct trapframe)
*
* Handle return from interrupts, traps and syscalls.
*/
SUPERALIGN_TEXT
.type doreti,@function
doreti:
FAKE_MCOUNT(bintr) /* init "from" bintr -> doreti */
doreti_next:
/*
* Check if ASTs can be handled now. PSL_VM must be checked first
* since segment registers only have an RPL in non-VM86 mode.
*/
testl $PSL_VM,TF_EFLAGS(%esp) /* are we in vm86 mode? */
jz doreti_notvm86
cmpl $1,in_vm86call /* are we in a vm86 call? */
jne doreti_ast /* can handle ASTs now if not */
jmp doreti_exit
doreti_notvm86:
testb $SEL_RPL_MASK,TF_CS(%esp) /* are we in user mode? */
jz doreti_exit /* can't handle ASTs now if not */
doreti_ast:
/*
* Check for ASTs atomically with returning. Disabling CPU
* interrupts provides sufficient locking evein the SMP case,
* since we will be informed of any new ASTs by an IPI.
*/
cli
movl PCPU(CURTHREAD),%eax
movl TD_KSE(%eax), %eax
testl $KEF_ASTPENDING | KEF_NEEDRESCHED,KE_FLAGS(%eax)
je doreti_exit
sti
pushl %esp /* pass a pointer to the trapframe */
call ast
add $4,%esp
jmp doreti_ast
/*
* doreti_exit: pop registers, iret.
*
* The segment register pop is a special case, since it may
* fault if (for example) a sigreturn specifies bad segment
* registers. The fault is handled in trap.c.
*/
doreti_exit:
MEXITCOUNT
.globl doreti_popl_fs
doreti_popl_fs:
popl %fs
.globl doreti_popl_es
doreti_popl_es:
popl %es
.globl doreti_popl_ds
doreti_popl_ds:
popl %ds
popal
addl $8,%esp
.globl doreti_iret
doreti_iret:
iret
/*
* doreti_iret_fault and friends. Alternative return code for
* the case where we get a fault in the doreti_exit code
* above. trap() (i386/i386/trap.c) catches this specific
* case, sends the process a signal and continues in the
* corresponding place in the code below.
*/
ALIGN_TEXT
.globl doreti_iret_fault
doreti_iret_fault:
subl $8,%esp
pushal
pushl %ds
.globl doreti_popl_ds_fault
doreti_popl_ds_fault:
pushl %es
.globl doreti_popl_es_fault
doreti_popl_es_fault:
pushl %fs
.globl doreti_popl_fs_fault
doreti_popl_fs_fault:
movl $0,TF_ERR(%esp) /* XXX should be the error code */
movl $T_PROTFLT,TF_TRAPNO(%esp)
jmp alltraps_with_regs_pushed
#ifdef APIC_IO
#include "i386/isa/apic_ipl.s"
#else
#include "i386/isa/icu_ipl.s"
#endif /* APIC_IO */