When a fault triggers a task switch, the error code, if existent, has to be pushed on the new task's stack. Implement the missing bits.
Signed-off-by: Jan Kiszka <[email protected]> --- This is a backport of the proposed fix for master. It applies at least down to 2.6.32 and should be considered for the stable queues. arch/x86/include/asm/kvm_host.h | 3 ++- arch/x86/include/asm/svm.h | 1 + arch/x86/kvm/svm.c | 11 ++++++++++- arch/x86/kvm/vmx.c | 12 +++++++++++- arch/x86/kvm/x86.c | 17 ++++++++++++++++- 5 files changed, 40 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 06d9e79..94bb19b 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -616,7 +616,8 @@ int emulator_set_dr(struct x86_emulate_ctxt *ctxt, int dr, void kvm_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg); int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector, int seg); -int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason); +int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason, + bool has_error_code, u32 error_code); void kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0); void kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3); diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h index 38638cd..7d13531 100644 --- a/arch/x86/include/asm/svm.h +++ b/arch/x86/include/asm/svm.h @@ -238,6 +238,7 @@ struct __attribute__ ((__packed__)) vmcb { #define SVM_EXITINFOSHIFT_TS_REASON_IRET 36 #define SVM_EXITINFOSHIFT_TS_REASON_JMP 38 +#define SVM_EXITINFOSHIFT_TS_HAS_ERROR_CODE 44 #define SVM_EXIT_READ_CR0 0x000 #define SVM_EXIT_READ_CR3 0x003 diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 52f78dd..17668db 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -2012,6 +2012,8 @@ static int task_switch_interception(struct vcpu_svm *svm) svm->vmcb->control.exit_int_info & SVM_EXITINTINFO_TYPE_MASK; uint32_t idt_v = svm->vmcb->control.exit_int_info & SVM_EXITINTINFO_VALID; + bool has_error_code = false; + u32 error_code = 0; tss_selector = (u16)svm->vmcb->control.exit_info_1; @@ -2032,6 +2034,12 @@ static int task_switch_interception(struct vcpu_svm *svm) svm->vcpu.arch.nmi_injected = false; break; case SVM_EXITINTINFO_TYPE_EXEPT: + if (svm->vmcb->control.exit_info_2 & + (1ULL << SVM_EXITINFOSHIFT_TS_HAS_ERROR_CODE)) { + has_error_code = true; + error_code = + (u32)svm->vmcb->control.exit_info_2; + } kvm_clear_exception_queue(&svm->vcpu); break; case SVM_EXITINTINFO_TYPE_INTR: @@ -2048,7 +2056,8 @@ static int task_switch_interception(struct vcpu_svm *svm) (int_vec == OF_VECTOR || int_vec == BP_VECTOR))) skip_emulated_instruction(&svm->vcpu); - return kvm_task_switch(&svm->vcpu, tss_selector, reason); + return kvm_task_switch(&svm->vcpu, tss_selector, reason, + has_error_code, error_code); } static int cpuid_interception(struct vcpu_svm *svm) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 14873b9..5ba2d35 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3286,6 +3286,8 @@ static int handle_task_switch(struct kvm_vcpu *vcpu) { struct vcpu_vmx *vmx = to_vmx(vcpu); unsigned long exit_qualification; + bool has_error_code = false; + u32 error_code = 0; u16 tss_selector; int reason, type, idt_v; @@ -3308,6 +3310,13 @@ static int handle_task_switch(struct kvm_vcpu *vcpu) kvm_clear_interrupt_queue(vcpu); break; case INTR_TYPE_HARD_EXCEPTION: + if (vmx->idt_vectoring_info & + VECTORING_INFO_DELIVER_CODE_MASK) { + has_error_code = true; + error_code = + vmcs_read32(IDT_VECTORING_ERROR_CODE); + } + /* fall through */ case INTR_TYPE_SOFT_EXCEPTION: kvm_clear_exception_queue(vcpu); break; @@ -3322,7 +3331,8 @@ static int handle_task_switch(struct kvm_vcpu *vcpu) type != INTR_TYPE_NMI_INTR)) skip_emulated_instruction(vcpu); - if (!kvm_task_switch(vcpu, tss_selector, reason)) + if (!kvm_task_switch(vcpu, tss_selector, reason, has_error_code, + error_code)) return 0; /* clear all local breakpoint enable flags */ diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 35eabd8..fa90e4e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5137,7 +5137,8 @@ out: return ret; } -int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason) +int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason, + bool has_error_code, u32 error_code) { struct kvm_segment tr_seg; struct desc_struct cseg_desc; @@ -5213,6 +5214,20 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason) seg_desct_to_kvm_desct(&nseg_desc, tss_selector, &tr_seg); tr_seg.type = 11; kvm_set_segment(vcpu, &tr_seg, VCPU_SREG_TR); + + if (ret && has_error_code) { + unsigned size = (nseg_desc.type & 8) ? 4 : 2; + unsigned long rsp = + kvm_register_read(vcpu, VCPU_REGS_RSP) - size; + + if (kvm_write_guest(vcpu->kvm, + get_segment_base(vcpu, VCPU_SREG_SS) + rsp, + &error_code, size)) + ret = 0; + else + kvm_register_write(vcpu, VCPU_REGS_RSP, rsp); + } + out: return ret; } -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
