KVM: s390: fix handling of lctl[g]/stctl[g]

According to the architecture all instructions are suppressing if memory
access is prohibited due to DAT protection, unless stated otherwise for
an instruction.
The lctl[g]/stctl[g] implementations handled this incorrectly since
control register handling was done piecemeal, which means they had
terminating instead of suppressing semantics.
This patch fixes this.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index 9c565b6b4ccb78652654f89517a06410eb360104..9bde32f66eb5741f60809eaf3f98bb196767f34f 100644 (file)
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -762,8 +762,8 @@ int kvm_s390_handle_lctl(struct kvm_vcpu *vcpu)
 {
        int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
        int reg3 = vcpu->arch.sie_block->ipa & 0x000f;
-       u32 val = 0;
-       int reg, rc;
+       int reg, rc, nr_regs;
+       u32 ctl_array[16];
        u64 ga;
 
        vcpu->stat.instruction_lctl++;
@@ -779,14 +779,15 @@ int kvm_s390_handle_lctl(struct kvm_vcpu *vcpu)
        VCPU_EVENT(vcpu, 5, "lctl r1:%x, r3:%x, addr:%llx", reg1, reg3, ga);
        trace_kvm_s390_handle_lctl(vcpu, 0, reg1, reg3, ga);
 
+       nr_regs = ((reg3 - reg1) & 0xf) + 1;
+       rc = read_guest(vcpu, ga, ctl_array, nr_regs * sizeof(u32));
+       if (rc)
+               return kvm_s390_inject_prog_cond(vcpu, rc);
        reg = reg1;
+       nr_regs = 0;
        do {
-               rc = read_guest(vcpu, ga, &val, sizeof(val));
-               if (rc)
-                       return kvm_s390_inject_prog_cond(vcpu, rc);
                vcpu->arch.sie_block->gcr[reg] &= 0xffffffff00000000ul;
-               vcpu->arch.sie_block->gcr[reg] |= val;
-               ga += 4;
+               vcpu->arch.sie_block->gcr[reg] |= ctl_array[nr_regs++];
                if (reg == reg3)
                        break;
                reg = (reg + 1) % 16;
@@ -799,9 +800,9 @@ int kvm_s390_handle_stctl(struct kvm_vcpu *vcpu)
 {
        int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
        int reg3 = vcpu->arch.sie_block->ipa & 0x000f;
+       int reg, rc, nr_regs;
+       u32 ctl_array[16];
        u64 ga;
-       u32 val;
-       int reg, rc;
 
        vcpu->stat.instruction_stctl++;
 
@@ -817,26 +818,24 @@ int kvm_s390_handle_stctl(struct kvm_vcpu *vcpu)
        trace_kvm_s390_handle_stctl(vcpu, 0, reg1, reg3, ga);
 
        reg = reg1;
+       nr_regs = 0;
        do {
-               val = vcpu->arch.sie_block->gcr[reg] &  0x00000000fffffffful;
-               rc = write_guest(vcpu, ga, &val, sizeof(val));
-               if (rc)
-                       return kvm_s390_inject_prog_cond(vcpu, rc);
-               ga += 4;
+               ctl_array[nr_regs++] = vcpu->arch.sie_block->gcr[reg];
                if (reg == reg3)
                        break;
                reg = (reg + 1) % 16;
        } while (1);
-
-       return 0;
+       rc = write_guest(vcpu, ga, ctl_array, nr_regs * sizeof(u32));
+       return rc ? kvm_s390_inject_prog_cond(vcpu, rc) : 0;
 }
 
 static int handle_lctlg(struct kvm_vcpu *vcpu)
 {
        int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
        int reg3 = vcpu->arch.sie_block->ipa & 0x000f;
-       u64 ga, val;
-       int reg, rc;
+       int reg, rc, nr_regs;
+       u64 ctl_array[16];
+       u64 ga;
 
        vcpu->stat.instruction_lctlg++;
 
@@ -848,17 +847,17 @@ static int handle_lctlg(struct kvm_vcpu *vcpu)
        if (ga & 7)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
 
-       reg = reg1;
-
        VCPU_EVENT(vcpu, 5, "lctlg r1:%x, r3:%x, addr:%llx", reg1, reg3, ga);
        trace_kvm_s390_handle_lctl(vcpu, 1, reg1, reg3, ga);
 
+       nr_regs = ((reg3 - reg1) & 0xf) + 1;
+       rc = read_guest(vcpu, ga, ctl_array, nr_regs * sizeof(u64));
+       if (rc)
+               return kvm_s390_inject_prog_cond(vcpu, rc);
+       reg = reg1;
+       nr_regs = 0;
        do {
-               rc = read_guest(vcpu, ga, &val, sizeof(val));
-               if (rc)
-                       return kvm_s390_inject_prog_cond(vcpu, rc);
-               vcpu->arch.sie_block->gcr[reg] = val;
-               ga += 8;
+               vcpu->arch.sie_block->gcr[reg] = ctl_array[nr_regs++];
                if (reg == reg3)
                        break;
                reg = (reg + 1) % 16;
@@ -871,8 +870,9 @@ static int handle_stctg(struct kvm_vcpu *vcpu)
 {
        int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
        int reg3 = vcpu->arch.sie_block->ipa & 0x000f;
-       u64 ga, val;
-       int reg, rc;
+       int reg, rc, nr_regs;
+       u64 ctl_array[16];
+       u64 ga;
 
        vcpu->stat.instruction_stctg++;
 
@@ -884,23 +884,19 @@ static int handle_stctg(struct kvm_vcpu *vcpu)
        if (ga & 7)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
 
-       reg = reg1;
-
        VCPU_EVENT(vcpu, 5, "stctg r1:%x, r3:%x, addr:%llx", reg1, reg3, ga);
        trace_kvm_s390_handle_stctl(vcpu, 1, reg1, reg3, ga);
 
+       reg = reg1;
+       nr_regs = 0;
        do {
-               val = vcpu->arch.sie_block->gcr[reg];
-               rc = write_guest(vcpu, ga, &val, sizeof(val));
-               if (rc)
-                       return kvm_s390_inject_prog_cond(vcpu, rc);
-               ga += 8;
+               ctl_array[nr_regs++] = vcpu->arch.sie_block->gcr[reg];
                if (reg == reg3)
                        break;
                reg = (reg + 1) % 16;
        } while (1);
-
-       return 0;
+       rc = write_guest(vcpu, ga, ctl_array, nr_regs * sizeof(u64));
+       return rc ? kvm_s390_inject_prog_cond(vcpu, rc) : 0;
 }
 
 static const intercept_handler_t eb_handlers[256] = {