There isn't really a valid reason for kvm to intercept cr* reads
on svm hardware.  The current kvm code just ends up returning
the register

Signed-off-by: Joel Schopp <joel.sch...@amd.com>
---
 arch/x86/kvm/svm.c |   41 ++++-------------------------------------
 1 file changed, 4 insertions(+), 37 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index cc618c8..c3d10e6 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1090,9 +1090,6 @@ static void init_vmcb(struct vcpu_svm *svm)
        svm->vcpu.fpu_active = 1;
        svm->vcpu.arch.hflags = 0;
 
-       set_cr_intercept(svm, INTERCEPT_CR0_READ);
-       set_cr_intercept(svm, INTERCEPT_CR3_READ);
-       set_cr_intercept(svm, INTERCEPT_CR4_READ);
        set_cr_intercept(svm, INTERCEPT_CR0_WRITE);
        set_cr_intercept(svm, INTERCEPT_CR3_WRITE);
        set_cr_intercept(svm, INTERCEPT_CR4_WRITE);
@@ -1174,7 +1171,6 @@ static void init_vmcb(struct vcpu_svm *svm)
                control->nested_ctl = 1;
                clr_intercept(svm, INTERCEPT_INVLPG);
                clr_exception_intercept(svm, PF_VECTOR);
-               clr_cr_intercept(svm, INTERCEPT_CR3_READ);
                clr_cr_intercept(svm, INTERCEPT_CR3_WRITE);
                save->g_pat = 0x0007040600070406ULL;
                save->cr3 = 0;
@@ -2968,29 +2964,10 @@ static int cr_interception(struct vcpu_svm *svm)
                        kvm_queue_exception(&svm->vcpu, UD_VECTOR);
                        return 1;
                }
-       } else { /* mov from cr */
-               switch (cr) {
-               case 0:
-                       val = kvm_read_cr0(&svm->vcpu);
-                       break;
-               case 2:
-                       val = svm->vcpu.arch.cr2;
-                       break;
-               case 3:
-                       val = kvm_read_cr3(&svm->vcpu);
-                       break;
-               case 4:
-                       val = kvm_read_cr4(&svm->vcpu);
-                       break;
-               case 8:
-                       val = kvm_get_cr8(&svm->vcpu);
-                       break;
-               default:
-                       WARN(1, "unhandled read from CR%d", cr);
-                       kvm_queue_exception(&svm->vcpu, UD_VECTOR);
-                       return 1;
-               }
-               kvm_register_write(&svm->vcpu, reg, val);
+       } else { /* mov from cr, should never trap in svm */
+               WARN(1, "unhandled read from CR%d", cr);
+               kvm_queue_exception(&svm->vcpu, UD_VECTOR);
+               return 1;
        }
        kvm_complete_insn_gp(&svm->vcpu, err);
 
@@ -3321,10 +3298,6 @@ static int mwait_interception(struct vcpu_svm *svm)
 }
 
 static int (*const svm_exit_handlers[])(struct vcpu_svm *svm) = {
-       [SVM_EXIT_READ_CR0]                     = cr_interception,
-       [SVM_EXIT_READ_CR3]                     = cr_interception,
-       [SVM_EXIT_READ_CR4]                     = cr_interception,
-       [SVM_EXIT_READ_CR8]                     = cr_interception,
        [SVM_EXIT_CR0_SEL_WRITE]                = emulate_on_interception,
        [SVM_EXIT_WRITE_CR0]                    = cr_interception,
        [SVM_EXIT_WRITE_CR3]                    = cr_interception,
@@ -4151,11 +4124,9 @@ static const struct __x86_intercept {
        u32 exit_code;
        enum x86_intercept_stage stage;
 } x86_intercept_map[] = {
-       [x86_intercept_cr_read]         = POST_EX(SVM_EXIT_READ_CR0),
        [x86_intercept_cr_write]        = POST_EX(SVM_EXIT_WRITE_CR0),
        [x86_intercept_clts]            = POST_EX(SVM_EXIT_WRITE_CR0),
        [x86_intercept_lmsw]            = POST_EX(SVM_EXIT_WRITE_CR0),
-       [x86_intercept_smsw]            = POST_EX(SVM_EXIT_READ_CR0),
        [x86_intercept_dr_read]         = POST_EX(SVM_EXIT_READ_DR0),
        [x86_intercept_dr_write]        = POST_EX(SVM_EXIT_WRITE_DR0),
        [x86_intercept_sldt]            = POST_EX(SVM_EXIT_LDTR_READ),
@@ -4221,10 +4192,6 @@ static int svm_check_intercept(struct kvm_vcpu *vcpu,
                goto out;
 
        switch (icpt_info.exit_code) {
-       case SVM_EXIT_READ_CR0:
-               if (info->intercept == x86_intercept_cr_read)
-                       icpt_info.exit_code += info->modrm_reg;
-               break;
        case SVM_EXIT_WRITE_CR0: {
                unsigned long cr0, val;
                u64 intercept;

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