/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2007 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #include <sys/asm_linkage.h> #include <sys/hypervisor.h> #include <sys/privregs.h> #include <sys/segments.h> #include <sys/traptrace.h> #include <sys/trap.h> #include <sys/psw.h> #include <sys/x86_archext.h> #include <sys/asm_misc.h> #include "assym.h" /* * The stack frame for events is exactly that of an x86 hardware * interrupt. * * The stack frame for a failsafe callback is augmented with saved * values for segment registers: * * i386 * %ds, %es, %fs, %gs, %eip, %cs, %eflags [, %oldesp, %oldss ] * * On amd64 the stack frame for events is exactly that of an hardware * interrupt with the addition of rcx and r11. * * The stack frame for a failsafe callback is augmented with saved * values for segment registers: * * amd64 * %rcx, %r11, %ds, %es, %fs, %gs, %rip, %cs, %rflags, * [, %oldrsp, %oldss ] * * The hypervisor does this to allow the guest OS to handle returns * to processes which have bad segment registers. * * [See comments in xen/arch/x86/[x86_64,x86_32]/entry.S] * * We will construct a fully fledged 'struct regs' and call trap * with a #gp fault. */ ENTRY(xen_failsafe_callback) /* * The saved values of rcx and r11 are on the top of the stack. * pop them and let INTR_PUSH save them. We drop ds, es, fs and * gs since the hypervisor will have already loaded these for us. * If any were bad and faulted the hypervisor would have loaded * them with the null selctor. */ XPV_TRAP_POP /* rcx, r11 */ /* * XXPV * If the current segregs are provided for us on the stack by * the hypervisor then we should simply move them into their proper * location in the regs struct? */ addq $_CONST(_MUL(4, CLONGSIZE)), %rsp /* * XXPV * It would be nice to somehow figure out which selector caused * #gp fault. */ pushq $0 /* dummy error */ pushq $T_GPFLT INTR_PUSH INTGATE_INIT_KERNEL_FLAGS /* * We're here because HYPERVISOR_IRET to userland failed due to a * bad %cs value. Rewrite %cs, %ss and %rip on the stack so trap * will know to handle this with kern_gpfault and kill the currently * running process. */ movq $KCS_SEL, REGOFF_CS(%rsp) movq $KDS_SEL, REGOFF_SS(%rsp) leaq nopop_sys_rtt_syscall(%rip), %rdi movq %rdi, REGOFF_RIP(%rsp) TRACE_PTR(%rdi, %rbx, %ebx, %rcx, $TT_EVENT) /* Uses labels 8 and 9 */ TRACE_REGS(%rdi, %rsp, %rbx, %rcx) /* Uses label 9 */ TRACE_STAMP(%rdi) /* Clobbers %eax, %edx, uses 9 */ movq %rsp, %rbp TRACE_STACK(%rdi) movq %rbp, %rdi ENABLE_INTR_FLAGS movq %rbp, %rdi xorl %esi, %esi movl %gs:CPU_ID, %edx call trap /* trap(rp, addr, cpuid) handles all trap */ jmp _sys_rtt SET_SIZE(xen_failsafe_callback) ENTRY(xen_callback) XPV_TRAP_POP pushq $0 /* dummy error */ pushq $T_AST INTR_PUSH INTGATE_INIT_KERNEL_FLAGS /* (set kernel flag values) */ TRACE_PTR(%rdi, %rbx, %ebx, %rcx, $TT_EVENT) /* Uses labels 8 and 9 */ TRACE_REGS(%rdi, %rsp, %rbx, %rcx) /* Uses label 9 */ TRACE_STAMP(%rdi) /* Clobbers %eax, %edx, uses 9 */ movq %rsp, %rbp TRACE_STACK(%rdi) movq %rdi, %rsi /* rsi = trap trace recode pointer */ movq %rbp, %rdi /* rdi = struct regs pointer */ call xen_callback_handler jmp _sys_rtt_ints_disabled /*NOTREACHED*/ SET_SIZE(xen_callback)
