exception.s revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Copyright (c) 1989, 1990 William F. Jolitz.
* Copyright (c) 1990 The Regents of the University of California.
* 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.
* 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.
*
* $FreeBSD: src/sys/amd64/amd64/exception.S,v 1.113 2003/10/15 02:04:52 peter Exp $
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/asm_linkage.h>
#include <sys/asm_misc.h>
#include <sys/trap.h>
#include <sys/psw.h>
#include <sys/regset.h>
#include <sys/privregs.h>
#include <sys/dtrace.h>
#include <sys/traptrace.h>
/*
* only one routine in this file is interesting to lint
*/
#if defined(__lint)
void
ndptrap_frstor(void)
{}
#else
#include "assym.h"
/*
* push $0 on stack for traps that do not
* generate an error code. This is so the rest
* of the kernel can expect a consistent stack
* from from any exception.
*/
#define TRAP_NOERR(trapno) \
push $0; \
push $trapno
/*
* error code already pushed by hw
* onto stack.
*/
#define TRAP_ERR(trapno) \
push $trapno
/*
* #DE
*/
ENTRY_NP(div0trap)
TRAP_NOERR(T_ZERODIV) /* $0 */
jmp cmntrap
SET_SIZE(div0trap)
#if defined(__amd64)
/*
* #DB
*
* If we get here as a result of single-stepping a sysenter
* instruction, we suddenly find ourselves taking a #db
* in kernel mode -before- we've swapgs'ed. So before we can
* take the trap, we do the swapgs here, and fix the return
* %rip in trap() so that we return immediately after the
* swapgs in the sysenter handler to avoid doing the swapgs again.
*
* Nobody said that the design of sysenter was particularly
* elegant, did they?
*/
ENTRY_NP(dbgtrap)
pushq %r11
leaq sys_sysenter(%rip), %r11
cmpq %r11, 8(%rsp)
jne 1f
swapgs
1: popq %r11
TRAP_NOERR(T_SGLSTP) /* $1 */
jmp cmntrap
SET_SIZE(dbgtrap)
#elif defined(__i386)
/*
* #DB
*/
ENTRY_NP(dbgtrap)
TRAP_NOERR(T_SGLSTP) /* $1 */
jmp cmntrap
SET_SIZE(dbgtrap)
#endif
#if defined(__amd64)
/*
* Macro to set the gsbase or kgsbase to the address of the struct cpu
* for this processor. If we came from userland, set kgsbase else clear
* gs and set gsbase. We find the proper cpu struct by looping through
* the cpu structs for all processors till we find a match for the gdt
* of the trapping processor. The stack is expected to be pointing at
* The standard regs pushed by hardware on a trap (plus error code and trapno).
*/
#define SET_CPU_GSBASE \
subq $REGOFF_TRAPNO, %rsp; /* save regs */ \
movq %rax, REGOFF_RAX(%rsp); \
movq %rbx, REGOFF_RBX(%rsp); \
movq %rcx, REGOFF_RCX(%rsp); \
movq %rdx, REGOFF_RDX(%rsp); \
movq %rbp, REGOFF_RBP(%rsp); \
movq %rsp, %rbp; \
subq $16, %rsp; /* space for gdt */ \
sgdt 6(%rsp); \
movq 8(%rsp), %rcx; /* %rcx has gdt to match */ \
xorl %ebx, %ebx; /* loop index */ \
leaq cpu(%rip), %rdx; /* cpu pointer array */ \
1: \
movq (%rdx, %rbx, CLONGSIZE), %rax; /* get cpu[i] */ \
cmpq $0x0, %rax; /* cpu[i] == NULL ? */ \
je 2f; /* yes, continue */ \
cmpq %rcx, CPU_GDT(%rax); /* gdt == cpu[i]->cpu_gdt ? */ \
je 3f; /* yes, go set gsbase */ \
2: \
incl %ebx; /* i++ */ \
cmpl $NCPU, %ebx; /* i < NCPU ? */ \
jb 1b; /* yes, loop */ \
/* XXX BIG trouble if we fall thru here. We didn't find a gdt match */ \
3: \
movl $MSR_AMD_KGSBASE, %ecx; \
cmpw $KCS_SEL, REGOFF_CS(%rbp); /* trap from kernel? */ \
jne 4f; /* no, go set KGSBASE */ \
movl $MSR_AMD_GSBASE, %ecx; /* yes, set GSBASE */ \
mfence; /* OPTERON_ERRATUM_88 */ \
4: \
movq %rax, %rdx; /* write base register */ \
shrq $32, %rdx; \
wrmsr; \
movq REGOFF_RDX(%rbp), %rdx; /* restore regs */ \
movq REGOFF_RCX(%rbp), %rcx; \
movq REGOFF_RBX(%rbp), %rbx; \
movq REGOFF_RAX(%rbp), %rax; \
movq %rbp, %rsp; \
movq REGOFF_RBP(%rsp), %rbp; \
addq $REGOFF_TRAPNO, %rsp /* pop stack */
#endif /* __amd64 */
.globl nmivect
.globl idt0_default_r
#if defined(__amd64)
/*
* #NMI
*/
ENTRY_NP(nmiint)
TRAP_NOERR(T_NMIFLT) /* $2 */
SET_CPU_GSBASE
/*
* Save all registers and setup segment registers
* with kernel selectors.
*/
INTR_PUSH
DISABLE_INTR_FLAGS /* and set the kernel flags */
TRACE_PTR(%r12, %rax, %eax, %rdx, $TT_TRAP)
TRACE_REGS(%r12, %rsp, %rax, %rbx)
TRACE_STAMP(%r12)
movq %rsp, %rbp
movq %rbp, %rdi
call av_dispatch_nmivect
INTR_POP
iretq
SET_SIZE(nmiint)
#elif defined(__i386)
/*
* #NMI
*/
ENTRY_NP(nmiint)
TRAP_NOERR(T_NMIFLT) /* $2 */
/*
* Save all registers and setup segment registers
* with kernel selectors.
*/
INTR_PUSH
/*
* setup pointer to reg struct as 2nd argument.
*/
movl %esp, %ebp
pushl %ebp
DISABLE_INTR_FLAGS
movl nmivect, %esi /* get autovect structure */
loop1:
cmpl $0, %esi /* if pointer is null */
je .intr_ret /* we're done */
movl AV_VECTOR(%esi), %edx /* get the interrupt routine */
pushl AV_INTARG1(%esi) /* get argument to interrupt routine */
call *%edx /* call interrupt routine with arg */
addl $4, %esp
movl AV_LINK(%esi), %esi /* get next routine on list */
jmp loop1 /* keep looping until end of list */
.intr_ret:
addl $4, %esp /* 'pop' %ebp */
INTR_POP_USER
iret
SET_SIZE(nmiint)
#endif /* __i386 */
/*
* #BP
*/
ENTRY_NP(brktrap)
#if defined(__amd64)
cmpw $KCS_SEL, 8(%rsp)
je bp_jmpud
#endif
TRAP_NOERR(T_BPTFLT) /* $3 */
jmp dtrace_trap
#if defined(__amd64)
bp_jmpud:
/*
* This is a breakpoint in the kernel -- it is very likely that this
* is DTrace-induced. To unify DTrace handling, we spoof this as an
* invalid opcode (#UD) fault. Note that #BP is a trap, not a fault --
* we must decrement the trapping %rip to make it appear as a fault.
* We then push a non-zero error code to indicate that this is coming
* from #BP.
*/
decq (%rsp)
push $1 /* error code -- non-zero for #BP */
jmp ud_kernel
#endif
SET_SIZE(brktrap)
/*
* #OF
*/
ENTRY_NP(ovflotrap)
TRAP_NOERR(T_OVFLW) /* $4 */
jmp cmntrap
SET_SIZE(ovflotrap)
/*
* #BR
*/
ENTRY_NP(boundstrap)
TRAP_NOERR(T_BOUNDFLT) /* $5 */
jmp cmntrap
SET_SIZE(boundstrap)
#if defined(__amd64)
ENTRY_NP(invoptrap)
cmpw $KCS_SEL, 8(%rsp)
jne ud_user
push $0 /* error code -- zero for #UD */
ud_kernel:
push $0xdddd /* a dummy trap number */
TRAP_PUSH
movq REGOFF_RIP(%rsp), %rdi
movq REGOFF_RSP(%rsp), %rsi
movq REGOFF_RAX(%rsp), %rdx
pushq (%rsi)
movq %rsp, %rsi
call dtrace_invop
ALTENTRY(dtrace_invop_callsite)
addq $8, %rsp
cmpl $DTRACE_INVOP_PUSHL_EBP, %eax
je ud_push
cmpl $DTRACE_INVOP_LEAVE, %eax
je ud_leave
cmpl $DTRACE_INVOP_NOP, %eax
je ud_nop
cmpl $DTRACE_INVOP_RET, %eax
je ud_ret
jmp ud_trap
ud_push:
/*
* We must emulate a "pushq %rbp". To do this, we pull the stack
* down 8 bytes, and then store the base pointer.
*/
INTR_POP
subq $16, %rsp /* make room for %rbp */
pushq %rax /* push temp */
movq 24(%rsp), %rax /* load calling RIP */
addq $1, %rax /* increment over trapping instr */
movq %rax, 8(%rsp) /* store calling RIP */
movq 32(%rsp), %rax /* load calling CS */
movq %rax, 16(%rsp) /* store calling CS */
movq 40(%rsp), %rax /* load calling RFLAGS */
movq %rax, 24(%rsp) /* store calling RFLAGS */
movq 48(%rsp), %rax /* load calling RSP */
subq $8, %rax /* make room for %rbp */
movq %rax, 32(%rsp) /* store calling RSP */
movq 56(%rsp), %rax /* load calling SS */
movq %rax, 40(%rsp) /* store calling SS */
movq 32(%rsp), %rax /* reload calling RSP */
movq %rbp, (%rax) /* store %rbp there */
popq %rax /* pop off temp */
iretq /* return from interrupt */
ud_leave:
/*
* We must emulate a "leave", which is the same as a "movq %rbp, %rsp"
* followed by a "popq %rbp". This is quite a bit simpler on amd64
* than it is on i386 -- we can exploit the fact that the %rsp is
* explicitly saved to effect the pop without having to reshuffle
* the other data pushed for the trap.
*/
INTR_POP
pushq %rax /* push temp */
movq 8(%rsp), %rax /* load calling RIP */
addq $1, %rax /* increment over trapping instr */
movq %rax, 8(%rsp) /* store calling RIP */
movq (%rbp), %rax /* get new %rbp */
addq $8, %rbp /* adjust new %rsp */
movq %rbp, 32(%rsp) /* store new %rsp */
movq %rax, %rbp /* set new %rbp */
popq %rax /* pop off temp */
iretq /* return from interrupt */
ud_nop:
/*
* We must emulate a "nop". This is obviously not hard: we need only
* advance the %rip by one.
*/
INTR_POP
incq (%rsp)
iretq
ud_ret:
INTR_POP
pushq %rax /* push temp */
movq 32(%rsp), %rax /* load %rsp */
movq (%rax), %rax /* load calling RIP */
movq %rax, 8(%rsp) /* store calling RIP */
addq $8, 32(%rsp) /* adjust new %rsp */
popq %rax /* pop off temp */
iretq /* return from interrupt */
ud_trap:
/*
* We're going to let the kernel handle this as a normal #UD. If,
* however, we came through #BP and are spoofing #UD (in this case,
* the stored error value will be non-zero), we need to de-spoof
* the trap by incrementing %rip and pushing T_BPTFLT.
*/
cmpq $0, REGOFF_ERR(%rsp)
je ud_ud
incq REGOFF_RIP(%rsp)
addq $REGOFF_RIP, %rsp
TRAP_NOERR(T_BPTFLT) /* $3 */
jmp cmntrap
ud_ud:
addq $REGOFF_RIP, %rsp
ud_user:
TRAP_NOERR(T_ILLINST)
jmp cmntrap
SET_SIZE(invoptrap)
#elif defined(__i386)
/*
* #UD
*/
ENTRY_NP(invoptrap)
/*
* If we are taking an invalid opcode trap while in the kernel, this
* is likely an FBT probe point.
*/
pushl %gs
cmpw $KGS_SEL, (%esp)
jne 8f
addl $4, %esp
pusha
pushl %eax /* push %eax -- may be return value */
pushl %esp /* push stack pointer */
addl $48, (%esp) /* adjust to incoming args */
pushl 40(%esp) /* push calling EIP */
call dtrace_invop
ALTENTRY(dtrace_invop_callsite)
addl $12, %esp
cmpl $DTRACE_INVOP_PUSHL_EBP, %eax
je 1f
cmpl $DTRACE_INVOP_POPL_EBP, %eax
je 2f
cmpl $DTRACE_INVOP_LEAVE, %eax
je 3f
cmpl $DTRACE_INVOP_NOP, %eax
je 4f
jmp 7f
1:
/*
* We must emulate a "pushl %ebp". To do this, we pull the stack
* down 4 bytes, and then store the base pointer.
*/
popa
subl $4, %esp /* make room for %ebp */
pushl %eax /* push temp */
movl 8(%esp), %eax /* load calling EIP */
incl %eax /* increment over LOCK prefix */
movl %eax, 4(%esp) /* store calling EIP */
movl 12(%esp), %eax /* load calling CS */
movl %eax, 8(%esp) /* store calling CS */
movl 16(%esp), %eax /* load calling EFLAGS */
movl %eax, 12(%esp) /* store calling EFLAGS */
movl %ebp, 16(%esp) /* push %ebp */
popl %eax /* pop off temp */
iret /* return from interrupt */
2:
/*
* We must emulate a "popl %ebp". To do this, we do the opposite of
* the above: we remove the %ebp from the stack, and squeeze up the
* saved state from the trap.
*/
popa
pushl %eax /* push temp */
movl 16(%esp), %ebp /* pop %ebp */
movl 12(%esp), %eax /* load calling EFLAGS */
movl %eax, 16(%esp) /* store calling EFLAGS */
movl 8(%esp), %eax /* load calling CS */
movl %eax, 12(%esp) /* store calling CS */
movl 4(%esp), %eax /* load calling EIP */
incl %eax /* increment over LOCK prefix */
movl %eax, 8(%esp) /* store calling EIP */
popl %eax /* pop off temp */
addl $4, %esp /* adjust stack pointer */
iret /* return from interrupt */
3:
/*
* We must emulate a "leave", which is the same as a "movl %ebp, %esp"
* followed by a "popl %ebp". This looks similar to the above, but
* requires two temporaries: one for the new base pointer, and one
* for the staging register.
*/
popa
pushl %eax /* push temp */
pushl %ebx /* push temp */
movl %ebp, %ebx /* set temp to old %ebp */
movl (%ebx), %ebp /* pop %ebp */
movl 16(%esp), %eax /* load calling EFLAGS */
movl %eax, (%ebx) /* store calling EFLAGS */
movl 12(%esp), %eax /* load calling CS */
movl %eax, -4(%ebx) /* store calling CS */
movl 8(%esp), %eax /* load calling EIP */
incl %eax /* increment over LOCK prefix */
movl %eax, -8(%ebx) /* store calling EIP */
movl %ebx, -4(%esp) /* temporarily store new %esp */
popl %ebx /* pop off temp */
popl %eax /* pop off temp */
movl -12(%esp), %esp /* set stack pointer */
subl $8, %esp /* adjust for three pushes, one pop */
iret /* return from interrupt */
4:
/*
* We must emulate a "nop". This is obviously not hard: we need only
* advance the %eip by one.
*/
popa
incl (%esp)
iret
7:
popa
pushl $0
pushl $T_ILLINST /* $6 */
jmp cmntrap
8:
addl $4, %esp
pushl $0
pushl $T_ILLINST /* $6 */
jmp cmntrap
SET_SIZE(invoptrap)
#endif /* __i386 */
#if defined(__amd64)
/*
* #NM
*/
ENTRY_NP(ndptrap)
/*
* We want to do this quickly as every lwp using fp will take this
* after a context switch -- we do the frequent path in ndptrap_frstor
* below; for all other cases, we let the trap code handle it
*/
pushq %rax
pushq %rbx
cmpw $KCS_SEL, 24(%rsp) /* did we come from kernel mode? */
jne 1f
LOADCPU(%rbx) /* if yes, don't swapgs */
jmp 2f
1:
swapgs /* if from user, need swapgs */
LOADCPU(%rbx)
swapgs
2:
cmpl $0, fpu_exists(%rip)
je .handle_in_trap /* let trap handle no fp case */
movq CPU_THREAD(%rbx), %rax /* %rax = curthread */
movl $FPU_EN, %ebx
movq T_LWP(%rax), %rax /* %rax = lwp */
testq %rax, %rax
jz .handle_in_trap /* should not happen? */
#if LWP_PCB_FPU != 0
addq $LWP_PCB_FPU, %rax /* &lwp->lwp_pcb.pcb_fpu */
#endif
testl %ebx, PCB_FPU_FLAGS(%rax)
jz .handle_in_trap /* must be the first fault */
clts
andl $_BITNOT(FPU_VALID), PCB_FPU_FLAGS(%rax)
#if FPU_CTX_FPU_REGS != 0
addq $FPU_CTX_FPU_REGS, %rax
#endif
/*
* the label below is used in trap.c to detect FP faults in
* kernel due to user fault.
*/
ALTENTRY(ndptrap_frstor)
fxrstor (%rax)
popq %rbx
popq %rax
iretq
.handle_in_trap:
popq %rbx
popq %rax
TRAP_NOERR(T_NOEXTFLT) /* $7 */
jmp cmninttrap
SET_SIZE(ndptrap_frstor)
SET_SIZE(ndptrap)
#elif defined(__i386)
ENTRY_NP(ndptrap)
/*
* We want to do this quickly as every lwp using fp will take this
* after a context switch -- we do the frequent path in fpnoextflt
* below; for all other cases, we let the trap code handle it
*/
pushl %eax
pushl %ebx
pushl %ds
pushl %gs
movl $KDS_SEL, %ebx
movw %bx, %ds
movl $KGS_SEL, %eax
movw %ax, %gs
LOADCPU(%ebx)
cmpl $0, fpu_exists
je .handle_in_trap /* let trap handle no fp case */
movl CPU_THREAD(%ebx), %eax /* %eax = curthread */
movl $FPU_EN, %ebx
movl T_LWP(%eax), %eax /* %eax = lwp */
testl %eax, %eax
jz .handle_in_trap /* should not happen? */
#if LWP_PCB_FPU != 0
addl $LWP_PCB_FPU, %eax /* &lwp->lwp_pcb.pcb_fpu */
#endif
testl %ebx, PCB_FPU_FLAGS(%eax)
jz .handle_in_trap /* must be the first fault */
clts
andl $_BITNOT(FPU_VALID), PCB_FPU_FLAGS(%eax)
#if FPU_CTX_FPU_REGS != 0
addl $FPU_CTX_FPU_REGS, %eax
#endif
/*
* the label below is used in trap.c to detect FP faults in kernel
* due to user fault.
*/
ALTENTRY(ndptrap_frstor)
.globl _patch_fxrstor_eax
_patch_fxrstor_eax:
frstor (%eax) /* may be patched to fxrstor */
nop /* (including this byte) */
popl %gs
popl %ds
popl %ebx
popl %eax
iret
.handle_in_trap:
popl %gs
popl %ds
popl %ebx
popl %eax
pushl $0
pushl $T_NOEXTFLT /* $7 */
jmp cmninttrap
SET_SIZE(ndptrap_frstor)
SET_SIZE(ndptrap)
#endif /* __i386 */
#if defined(__amd64)
/*
* #DF
*/
ENTRY_NP(syserrtrap)
pushq $T_DBLFLT
SET_CPU_GSBASE
/*
* We share this handler with kmdb (if kmdb is loaded). As such, we may
* have reached this point after encountering a #df in kmdb. If that
* happens, we'll still be on kmdb's IDT. We need to switch back to this
* CPU's IDT before proceeding. Furthermore, if we did arrive here from
* kmdb, kmdb is probably in a very sickly state, and shouldn't be
* entered from the panic flow. We'll suppress that entry by setting
* nopanicdebug.
*/
pushq %rax
subq $DESCTBR_SIZE, %rsp
sidt (%rsp)
movq %gs:CPU_IDT, %rax
cmpq %rax, DTR_BASE(%rsp)
je 1f
movq %rax, DTR_BASE(%rsp)
movw $_MUL(NIDT, GATE_DESC_SIZE), DTR_LIMIT(%rsp)
lidt (%rsp)
movl $1, nopanicdebug
1: addq $DESCTBR_SIZE, %rsp
popq %rax
DFTRAP_PUSH
/*
* freeze trap trace.
*/
#ifdef TRAPTRACE
leaq trap_trace_freeze(%rip), %r11
incl (%r11)
#endif
ENABLE_INTR_FLAGS
movq %rsp, %rdi /* &regs */
xorl %esi, %esi /* clear address */
xorl %edx, %edx /* cpuid = 0 */
call trap
SET_SIZE(syserrtrap)
#elif defined(__i386)
/*
* #DF
*/
ENTRY_NP(syserrtrap)
cli /* disable interrupts */
/*
* We share this handler with kmdb (if kmdb is loaded). As such, we may
* have reached this point after encountering a #df in kmdb. If that
* happens, we'll still be on kmdb's IDT. We need to switch back to this
* CPU's IDT before proceeding. Furthermore, if we did arrive here from
* kmdb, kmdb is probably in a very sickly state, and shouldn't be
* entered from the panic flow. We'll suppress that entry by setting
* nopanicdebug.
*/
subl $DESCTBR_SIZE, %esp
movl %gs:CPU_IDT, %eax
sidt (%esp)
cmpl DTR_BASE(%esp), %eax
je 1f
movl %eax, DTR_BASE(%esp)
movw $_MUL(NIDT, GATE_DESC_SIZE), DTR_LIMIT(%esp)
lidt (%esp)
movl $1, nopanicdebug
1: addl $DESCTBR_SIZE, %esp
/*
* Check the CPL in the TSS to see what mode
* (user or kernel) we took the fault in. At this
* point we are running in the context of the double
* fault task (dftss) but the CPU's task points to
* the previous task (ktss) where the process context
* has been saved as the result of the task switch.
*/
movl %gs:CPU_TSS, %eax /* get the TSS */
movl TSS_SS(%eax), %ebx /* save the fault SS */
movl TSS_ESP(%eax), %edx /* save the fault ESP */
testw $CPL_MASK, TSS_CS(%eax) /* user mode ? */
jz make_frame
movw TSS_SS0(%eax), %ss /* get on the kernel stack */
movl TSS_ESP0(%eax), %esp
/*
* Clear the NT flag to avoid a task switch when the process
* finally pops the EFL off the stack via an iret. Clear
* the TF flag since that is what the processor does for
* a normal exception. Clear the IE flag so that interrupts
* remain disabled.
*/
movl TSS_EFL(%eax), %ecx
andl $_BITNOT(PS_NT|PS_T|PS_IE), %ecx
pushl %ecx
popfl /* restore the EFL */
movw TSS_LDT(%eax), %cx /* restore the LDT */
lldt %cx
/*
* Restore process segment selectors.
*/
movw TSS_DS(%eax), %ds
movw TSS_ES(%eax), %es
movw TSS_FS(%eax), %fs
movw TSS_GS(%eax), %gs
/*
* Restore task segment selectors.
*/
movl $KDS_SEL, TSS_DS(%eax)
movl $KDS_SEL, TSS_ES(%eax)
movl $KDS_SEL, TSS_SS(%eax)
movl $KFS_SEL, TSS_FS(%eax)
movl $KGS_SEL, TSS_GS(%eax)
/*
* Clear the TS bit, the busy bits in both task
* descriptors, and switch tasks.
*/
clts
leal gdt0, %ecx
movl DFTSS_SEL+4(%ecx), %esi
andl $_BITNOT(0x200), %esi
movl %esi, DFTSS_SEL+4(%ecx)
movl KTSS_SEL+4(%ecx), %esi
andl $_BITNOT(0x200), %esi
movl %esi, KTSS_SEL+4(%ecx)
movw $KTSS_SEL, %cx
ltr %cx
/*
* Restore part of the process registers.
*/
movl TSS_EBP(%eax), %ebp
movl TSS_ECX(%eax), %ecx
movl TSS_ESI(%eax), %esi
movl TSS_EDI(%eax), %edi
make_frame:
/*
* Make a trap frame. Leave the error code (0) on
* the stack since the first word on a trap stack is
* unused anyway.
*/
pushl %ebx / fault SS
pushl %edx / fault ESP
pushl TSS_EFL(%eax) / fault EFL
pushl TSS_CS(%eax) / fault CS
pushl TSS_EIP(%eax) / fault EIP
pushl $0 / error code
pushl $T_DBLFLT / trap number 8
movl TSS_EBX(%eax), %ebx / restore EBX
movl TSS_EDX(%eax), %edx / restore EDX
movl TSS_EAX(%eax), %eax / restore EAX
sti / enable interrupts
jmp cmntrap
SET_SIZE(syserrtrap)
#endif /* __i386 */
ENTRY_NP(overrun)
push $0
TRAP_NOERR(T_EXTOVRFLT) /* $9 i386 only - not generated */
jmp cmninttrap
SET_SIZE(overrun)
/*
* #TS
*/
ENTRY_NP(invtsstrap)
TRAP_ERR(T_TSSFLT) /* $10 already have error code on stack */
jmp cmntrap
SET_SIZE(invtsstrap)
/*
* #NP
*/
ENTRY_NP(segnptrap)
TRAP_ERR(T_SEGFLT) /* $11 already have error code on stack */
#if defined(__amd64)
SET_CPU_GSBASE
#endif
jmp cmntrap
SET_SIZE(segnptrap)
/*
* #SS
*/
ENTRY_NP(stktrap)
TRAP_ERR(T_STKFLT) /* $12 already have error code on stack */
jmp cmntrap
SET_SIZE(stktrap)
/*
* #GP
*/
ENTRY_NP(gptrap)
TRAP_ERR(T_GPFLT) /* $13 already have error code on stack */
#if defined(__amd64)
SET_CPU_GSBASE
#endif
jmp cmntrap
SET_SIZE(gptrap)
/*
* #PF
*/
ENTRY_NP(pftrap)
TRAP_ERR(T_PGFLT) /* $14 already have error code on stack */
jmp cmntrap
SET_SIZE(pftrap)
#if !defined(__amd64)
/*
* #PF pentium bug workaround
*/
ENTRY_NP(pentium_pftrap)
pushl %eax
movl %cr2, %eax
andl $MMU_STD_PAGEMASK, %eax
cmpl %eax, %cs:idt0_default_r+2 /* fixme */
je check_for_user_address
user_mode:
popl %eax
pushl $T_PGFLT /* $14 */
jmp cmntrap
check_for_user_address:
/*
* Before we assume that we have an unmapped trap on our hands,
* check to see if this is a fault from user mode. If it is,
* we'll kick back into the page fault handler.
*/
movl 4(%esp), %eax /* error code */
andl $PF_ERR_USER, %eax
jnz user_mode
/*
* We now know that this is the invalid opcode trap.
*/
popl %eax
addl $4, %esp /* pop error code */
jmp invoptrap
SET_SIZE(pentium_pftrap)
#endif /* !__amd64 */
ENTRY_NP(resvtrap)
TRAP_NOERR(15) /* (reserved) */
jmp cmntrap
SET_SIZE(resvtrap)
/*
* #MF
*/
ENTRY_NP(ndperr)
TRAP_NOERR(T_EXTERRFLT) /* $16 */
jmp cmninttrap
SET_SIZE(ndperr)
/*
* #AC
*/
ENTRY_NP(achktrap)
TRAP_ERR(T_ALIGNMENT) /* $17 */
jmp cmntrap
SET_SIZE(achktrap)
/*
* #MC
*/
ENTRY_NP(mcetrap)
TRAP_NOERR(T_MCE) /* $18 */
jmp cmninttrap
SET_SIZE(mcetrap)
/*
* #XF
*/
ENTRY_NP(xmtrap)
TRAP_NOERR(T_SIMDFPE) /* $19 */
jmp cmntrap
SET_SIZE(xmtrap)
ENTRY_NP(invaltrap)
TRAP_NOERR(30) /* very invalid */
jmp cmntrap
SET_SIZE(invaltrap)
ENTRY_NP(invalint)
TRAP_NOERR(31) /* even more so */
jmp cmnint
SET_SIZE(invalint)
.globl fasttable
#if defined(__amd64)
ENTRY_NP(fasttrap)
cmpl $T_LASTFAST, %eax
ja 1f
orl %eax, %eax /* (zero extend top 32-bits) */
leaq fasttable(%rip), %r11
leaq (%r11, %rax, CLONGSIZE), %r11
jmp *(%r11)
1:
/*
* Fast syscall number was illegal. Make it look
* as if the INT failed. Modify %rip to point before the
* INT, push the expected error code and fake a GP fault.
*
* XXX Why make the error code be offset into idt + 1?
* Instead we should push a real (soft?) error code
* on the stack and #gp handler could know about fasttraps?
*/
subq $2, (%rsp) /* XXX int insn 2-bytes */
pushq $_CONST(_MUL(T_FASTTRAP, GATE_DESC_SIZE) + 2)
jmp gptrap
SET_SIZE(fasttrap)
#elif defined(__i386)
ENTRY_NP(fasttrap)
cmpl $T_LASTFAST, %eax
ja 1f
jmp *%cs:fasttable(, %eax, CLONGSIZE)
1:
/*
* Fast syscall number was illegal. Make it look
* as if the INT failed. Modify %eip to point before the
* INT, push the expected error code and fake a GP fault.
*
* XXX Why make the error code be offset into idt + 1?
* Instead we should push a real (soft?) error code
* on the stack and #gp handler could know about fasttraps?
*/
subl $2, (%esp) /* XXX int insn 2-bytes */
pushl $_CONST(_MUL(T_FASTTRAP, GATE_DESC_SIZE) + 2)
jmp gptrap
SET_SIZE(fasttrap)
#endif /* __i386 */
ENTRY_NP(dtrace_fasttrap)
TRAP_NOERR(T_DTRACE_PROBE)
jmp dtrace_trap
SET_SIZE(dtrace_fasttrap)
ENTRY_NP(dtrace_ret)
TRAP_NOERR(T_DTRACE_RET)
jmp dtrace_trap
SET_SIZE(dtrace_ret)
#if defined(__amd64)
/*
* RFLAGS 24 bytes up the stack from %rsp.
* XXX a constant would be nicer.
*/
ENTRY_NP(fast_null)
orq $PS_C, 24(%rsp) /* set carry bit in user flags */
iretq
SET_SIZE(fast_null)
#elif defined(__i386)
ENTRY_NP(fast_null)
orw $PS_C, 8(%esp) /* set carry bit in user flags */
iret
SET_SIZE(fast_null)
#endif /* __i386 */
/*
* Interrupts start at 32
*/
#define MKIVCT(n) \
ENTRY_NP(ivct/**/n) \
push $0; \
push $n - 0x20; \
jmp cmnint; \
SET_SIZE(ivct/**/n)
MKIVCT(32)
MKIVCT(33)
MKIVCT(34)
MKIVCT(35)
MKIVCT(36)
MKIVCT(37)
MKIVCT(38)
MKIVCT(39)
MKIVCT(40)
MKIVCT(41)
MKIVCT(42)
MKIVCT(43)
MKIVCT(44)
MKIVCT(45)
MKIVCT(46)
MKIVCT(47)
MKIVCT(48)
MKIVCT(49)
MKIVCT(50)
MKIVCT(51)
MKIVCT(52)
MKIVCT(53)
MKIVCT(54)
MKIVCT(55)
MKIVCT(56)
MKIVCT(57)
MKIVCT(58)
MKIVCT(59)
MKIVCT(60)
MKIVCT(61)
MKIVCT(62)
MKIVCT(63)
MKIVCT(64)
MKIVCT(65)
MKIVCT(66)
MKIVCT(67)
MKIVCT(68)
MKIVCT(69)
MKIVCT(70)
MKIVCT(71)
MKIVCT(72)
MKIVCT(73)
MKIVCT(74)
MKIVCT(75)
MKIVCT(76)
MKIVCT(77)
MKIVCT(78)
MKIVCT(79)
MKIVCT(80)
MKIVCT(81)
MKIVCT(82)
MKIVCT(83)
MKIVCT(84)
MKIVCT(85)
MKIVCT(86)
MKIVCT(87)
MKIVCT(88)
MKIVCT(89)
MKIVCT(90)
MKIVCT(91)
MKIVCT(92)
MKIVCT(93)
MKIVCT(94)
MKIVCT(95)
MKIVCT(96)
MKIVCT(97)
MKIVCT(98)
MKIVCT(99)
MKIVCT(100)
MKIVCT(101)
MKIVCT(102)
MKIVCT(103)
MKIVCT(104)
MKIVCT(105)
MKIVCT(106)
MKIVCT(107)
MKIVCT(108)
MKIVCT(109)
MKIVCT(110)
MKIVCT(111)
MKIVCT(112)
MKIVCT(113)
MKIVCT(114)
MKIVCT(115)
MKIVCT(116)
MKIVCT(117)
MKIVCT(118)
MKIVCT(119)
MKIVCT(120)
MKIVCT(121)
MKIVCT(122)
MKIVCT(123)
MKIVCT(124)
MKIVCT(125)
MKIVCT(126)
MKIVCT(127)
MKIVCT(128)
MKIVCT(129)
MKIVCT(130)
MKIVCT(131)
MKIVCT(132)
MKIVCT(133)
MKIVCT(134)
MKIVCT(135)
MKIVCT(136)
MKIVCT(137)
MKIVCT(138)
MKIVCT(139)
MKIVCT(140)
MKIVCT(141)
MKIVCT(142)
MKIVCT(143)
MKIVCT(144)
MKIVCT(145)
MKIVCT(146)
MKIVCT(147)
MKIVCT(148)
MKIVCT(149)
MKIVCT(150)
MKIVCT(151)
MKIVCT(152)
MKIVCT(153)
MKIVCT(154)
MKIVCT(155)
MKIVCT(156)
MKIVCT(157)
MKIVCT(158)
MKIVCT(159)
MKIVCT(160)
MKIVCT(161)
MKIVCT(162)
MKIVCT(163)
MKIVCT(164)
MKIVCT(165)
MKIVCT(166)
MKIVCT(167)
MKIVCT(168)
MKIVCT(169)
MKIVCT(170)
MKIVCT(171)
MKIVCT(172)
MKIVCT(173)
MKIVCT(174)
MKIVCT(175)
MKIVCT(176)
MKIVCT(177)
MKIVCT(178)
MKIVCT(179)
MKIVCT(180)
MKIVCT(181)
MKIVCT(182)
MKIVCT(183)
MKIVCT(184)
MKIVCT(185)
MKIVCT(186)
MKIVCT(187)
MKIVCT(188)
MKIVCT(189)
MKIVCT(190)
MKIVCT(191)
MKIVCT(192)
MKIVCT(193)
MKIVCT(194)
MKIVCT(195)
MKIVCT(196)
MKIVCT(197)
MKIVCT(198)
MKIVCT(199)
MKIVCT(200)
MKIVCT(201)
MKIVCT(202)
MKIVCT(203)
MKIVCT(204)
MKIVCT(205)
MKIVCT(206)
MKIVCT(207)
MKIVCT(208)
MKIVCT(209)
MKIVCT(210)
MKIVCT(211)
MKIVCT(212)
MKIVCT(213)
MKIVCT(214)
MKIVCT(215)
MKIVCT(216)
MKIVCT(217)
MKIVCT(218)
MKIVCT(219)
MKIVCT(220)
MKIVCT(221)
MKIVCT(222)
MKIVCT(223)
MKIVCT(224)
MKIVCT(225)
MKIVCT(226)
MKIVCT(227)
MKIVCT(228)
MKIVCT(229)
MKIVCT(230)
MKIVCT(231)
MKIVCT(232)
MKIVCT(233)
MKIVCT(234)
MKIVCT(235)
MKIVCT(236)
MKIVCT(237)
MKIVCT(238)
MKIVCT(239)
MKIVCT(240)
MKIVCT(241)
MKIVCT(242)
MKIVCT(243)
MKIVCT(244)
MKIVCT(245)
MKIVCT(246)
MKIVCT(247)
MKIVCT(248)
MKIVCT(249)
MKIVCT(250)
MKIVCT(251)
MKIVCT(252)
MKIVCT(253)
MKIVCT(254)
MKIVCT(255)
#endif /* __lint */