From d8b6ccfe2d40d2964feb992bf2026957c54e982a Mon Sep 17 00:00:00 2001 From: "kfraser@localhost.localdomain" Date: Thu, 21 Jun 2007 14:03:57 +0100 Subject: [PATCH] x86: clear guest's EFLAGS.RF after emulating instructions Signed-off-by: Jan Beulich --- xen/arch/x86/hvm/io.c | 1 + xen/arch/x86/hvm/platform.c | 3 +++ xen/arch/x86/hvm/vmx/vmx.c | 21 ++++++++++++--------- xen/arch/x86/traps.c | 2 ++ xen/arch/x86/x86_emulate.c | 1 + xen/include/asm-x86/hvm/svm/emulate.h | 1 + 6 files changed, 20 insertions(+), 9 deletions(-) diff --git a/xen/arch/x86/hvm/io.c b/xen/arch/x86/hvm/io.c index 0a99dd27d6..97e1215a58 100644 --- a/xen/arch/x86/hvm/io.c +++ b/xen/arch/x86/hvm/io.c @@ -858,6 +858,7 @@ void hvm_io_assist(void) } /* Copy register changes back into current guest state. */ + regs->eflags &= ~X86_EFLAGS_RF; hvm_load_cpu_guest_regs(v, regs); memcpy(guest_cpu_user_regs(), regs, HVM_CONTEXT_STACK_BYTES); diff --git a/xen/arch/x86/hvm/platform.c b/xen/arch/x86/hvm/platform.c index 2b173c18de..5de0770322 100644 --- a/xen/arch/x86/hvm/platform.c +++ b/xen/arch/x86/hvm/platform.c @@ -1065,6 +1065,7 @@ void handle_mmio(unsigned long gpa) } regs->eip += inst_len; /* advance %eip */ + regs->eflags &= ~X86_EFLAGS_RF; switch ( mmio_op->instr ) { case INSTR_MOV: @@ -1122,6 +1123,7 @@ void handle_mmio(unsigned long gpa) /* IO read --> memory write */ if ( dir == IOREQ_READ ) errcode |= PFEC_write_access; regs->eip -= inst_len; /* do not advance %eip */ + regs->eflags |= X86_EFLAGS_RF; /* RF was set by original #PF */ hvm_inject_exception(TRAP_page_fault, errcode, addr); return; } @@ -1150,6 +1152,7 @@ void handle_mmio(unsigned long gpa) /* Failed on the page-spanning copy. Inject PF into * the guest for the address where we failed */ regs->eip -= inst_len; /* do not advance %eip */ + regs->eflags |= X86_EFLAGS_RF; /* RF was set by #PF */ /* Must set CR2 at the failing address */ addr += size - rv; gdprintk(XENLOG_DEBUG, "Pagefault on non-io side of a " diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c index f36b58f261..bb5a48aa87 100644 --- a/xen/arch/x86/hvm/vmx/vmx.c +++ b/xen/arch/x86/hvm/vmx/vmx.c @@ -1315,16 +1315,20 @@ static int __get_instruction_length(void) static void inline __update_guest_eip(unsigned long inst_len) { - unsigned long current_eip, intr_shadow; + unsigned long x; - current_eip = __vmread(GUEST_RIP); - __vmwrite(GUEST_RIP, current_eip + inst_len); + x = __vmread(GUEST_RIP); + __vmwrite(GUEST_RIP, x + inst_len); - intr_shadow = __vmread(GUEST_INTERRUPTIBILITY_INFO); - if ( intr_shadow & (VMX_INTR_SHADOW_STI | VMX_INTR_SHADOW_MOV_SS) ) + x = __vmread(GUEST_RFLAGS); + if ( x & X86_EFLAGS_RF ) + __vmwrite(GUEST_RFLAGS, x & ~X86_EFLAGS_RF); + + x = __vmread(GUEST_INTERRUPTIBILITY_INFO); + if ( x & (VMX_INTR_SHADOW_STI | VMX_INTR_SHADOW_MOV_SS) ) { - intr_shadow &= ~(VMX_INTR_SHADOW_STI | VMX_INTR_SHADOW_MOV_SS); - __vmwrite(GUEST_INTERRUPTIBILITY_INFO, intr_shadow); + x &= ~(VMX_INTR_SHADOW_STI | VMX_INTR_SHADOW_MOV_SS); + __vmwrite(GUEST_INTERRUPTIBILITY_INFO, x); } } @@ -1896,7 +1900,7 @@ static void vmx_world_save(struct vcpu *v, struct vmx_assist_context *c) c->eip += __get_instruction_length(); /* Safe: MOV Cn, LMSW, CLTS */ c->esp = __vmread(GUEST_RSP); - c->eflags = __vmread(GUEST_RFLAGS); + c->eflags = __vmread(GUEST_RFLAGS) & ~X86_EFLAGS_RF; c->cr0 = v->arch.hvm_vmx.cpu_shadow_cr0; c->cr3 = v->arch.hvm_vmx.cpu_cr3; @@ -2272,7 +2276,6 @@ static int vmx_set_cr0(unsigned long value) "Enabling CR0.PE at %%eip 0x%lx", eip); if ( vmx_assist(v, VMX_ASSIST_RESTORE) ) { - eip = __vmread(GUEST_RIP); HVM_DBG_LOG(DBG_LEVEL_1, "Restoring to %%eip 0x%lx", eip); return 0; /* do not update eip! */ diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c index c14847a668..c26fde22f9 100644 --- a/xen/arch/x86/traps.c +++ b/xen/arch/x86/traps.c @@ -631,6 +631,7 @@ static int emulate_forced_invalid_op(struct cpu_user_regs *regs) regs->ecx = c; regs->edx = d; regs->eip = eip; + regs->eflags &= ~X86_EFLAGS_RF; return EXCRET_fault_fixed; } @@ -1787,6 +1788,7 @@ static int emulate_privileged_op(struct cpu_user_regs *regs) done: regs->eip = eip; + regs->eflags &= ~X86_EFLAGS_RF; return EXCRET_fault_fixed; fail: diff --git a/xen/arch/x86/x86_emulate.c b/xen/arch/x86/x86_emulate.c index 70262d6131..213da19f5d 100644 --- a/xen/arch/x86/x86_emulate.c +++ b/xen/arch/x86/x86_emulate.c @@ -1630,6 +1630,7 @@ x86_emulate( } /* Commit shadow register state. */ + _regs.eflags &= ~EF_RF; *ctxt->regs = _regs; done: diff --git a/xen/include/asm-x86/hvm/svm/emulate.h b/xen/include/asm-x86/hvm/svm/emulate.h index 8a4e139d22..8c183b89de 100644 --- a/xen/include/asm-x86/hvm/svm/emulate.h +++ b/xen/include/asm-x86/hvm/svm/emulate.h @@ -138,6 +138,7 @@ static void inline __update_guest_eip( { ASSERT(inst_len > 0); vmcb->rip += inst_len; + vmcb->rflags &= ~X86_EFLAGS_RF; } #endif /* __ASM_X86_HVM_SVM_EMULATE_H__ */ -- 2.30.2