KVM: s390: Fixed CC of SIGP SET_PREFIX handler

When SIGP SET_PREFIX is called with an illegal CPU id, it must return
the condition code 3 ("not operational") instead of 1. Also fixed the
order in which the checks are done - CC3 has a higher priority than CC1.
And while we're at it, this patch also get rid of the floating interrupt
lock here by using kvm_get_vcpu() to get the local_int struct of the
destination CPU.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

1 files changed, 8 insertions, 16 deletions

diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index fe9442d39f0e..466eefa18708 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -249,12 +249,18 @@ static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
                              u64 *reg)
 {
-        struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
-        struct kvm_s390_local_interrupt *li = NULL;
+        struct kvm_s390_local_interrupt *li;
+        struct kvm_vcpu *dst_vcpu = NULL;
         struct kvm_s390_interrupt_info *inti;
         int rc;
         u8 tmp;
 
+        if (cpu_addr < KVM_MAX_VCPUS)
+                dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
+        if (!dst_vcpu)
+                return SIGP_CC_NOT_OPERATIONAL;
+        li = &dst_vcpu->arch.local_int;
+
         /* make sure that the new value is valid memory */
         address = address & 0x7fffe000u;
         if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
@@ -268,18 +274,6 @@ static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
         if (!inti)
                 return SIGP_CC_BUSY;
 
-        spin_lock(&fi->lock);
-        if (cpu_addr < KVM_MAX_VCPUS)
-                li = fi->local_int[cpu_addr];
-
-        if (li == NULL) {
-                *reg &= 0xffffffff00000000UL;
-                *reg |= SIGP_STATUS_INCORRECT_STATE;
-                rc = SIGP_CC_STATUS_STORED;
-                kfree(inti);
-                goto out_fi;
-        }
-
         spin_lock_bh(&li->lock);
         /* cpu must be in stopped state */
         if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
@@ -302,8 +296,6 @@ static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
         VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
 out_li:
         spin_unlock_bh(&li->lock);
-out_fi:
-        spin_unlock(&fi->lock);
         return rc;
 }