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Diffstat (limited to 'arch/loongarch/kvm/vcpu.c')
-rw-r--r--arch/loongarch/kvm/vcpu.c81
1 files changed, 40 insertions, 41 deletions
diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c
index 27701991886d..36106922b5d7 100644
--- a/arch/loongarch/kvm/vcpu.c
+++ b/arch/loongarch/kvm/vcpu.c
@@ -298,74 +298,73 @@ static int _kvm_setcsr(struct kvm_vcpu *vcpu, unsigned int id, u64 val)
return ret;
}
-static int _kvm_get_cpucfg(int id, u64 *v)
+static int _kvm_get_cpucfg_mask(int id, u64 *v)
{
- int ret = 0;
-
- if (id < 0 && id >= KVM_MAX_CPUCFG_REGS)
+ if (id < 0 || id >= KVM_MAX_CPUCFG_REGS)
return -EINVAL;
switch (id) {
case 2:
- /* Return CPUCFG2 features which have been supported by KVM */
+ /* CPUCFG2 features unconditionally supported by KVM */
*v = CPUCFG2_FP | CPUCFG2_FPSP | CPUCFG2_FPDP |
CPUCFG2_FPVERS | CPUCFG2_LLFTP | CPUCFG2_LLFTPREV |
CPUCFG2_LAM;
/*
- * If LSX is supported by CPU, it is also supported by KVM,
- * as we implement it.
+ * For the ISA extensions listed below, if one is supported
+ * by the host, then it is also supported by KVM.
*/
if (cpu_has_lsx)
*v |= CPUCFG2_LSX;
- /*
- * if LASX is supported by CPU, it is also supported by KVM,
- * as we implement it.
- */
if (cpu_has_lasx)
*v |= CPUCFG2_LASX;
- break;
+ return 0;
default:
- ret = -EINVAL;
- break;
+ /*
+ * No restrictions on other valid CPUCFG IDs' values, but
+ * CPUCFG data is limited to 32 bits as the LoongArch ISA
+ * manual says (Volume 1, Section 2.2.10.5 "CPUCFG").
+ */
+ *v = U32_MAX;
+ return 0;
}
- return ret;
}
static int kvm_check_cpucfg(int id, u64 val)
{
- u64 mask;
- int ret = 0;
-
- if (id < 0 && id >= KVM_MAX_CPUCFG_REGS)
- return -EINVAL;
+ int ret;
+ u64 mask = 0;
- if (_kvm_get_cpucfg(id, &mask))
+ ret = _kvm_get_cpucfg_mask(id, &mask);
+ if (ret)
return ret;
+ if (val & ~mask)
+ /* Unsupported features and/or the higher 32 bits should not be set */
+ return -EINVAL;
+
switch (id) {
case 2:
- /* CPUCFG2 features checking */
- if (val & ~mask)
- /* The unsupported features should not be set */
- ret = -EINVAL;
- else if (!(val & CPUCFG2_LLFTP))
- /* The LLFTP must be set, as guest must has a constant timer */
- ret = -EINVAL;
- else if ((val & CPUCFG2_FP) && (!(val & CPUCFG2_FPSP) || !(val & CPUCFG2_FPDP)))
- /* Single and double float point must both be set when enable FP */
- ret = -EINVAL;
- else if ((val & CPUCFG2_LSX) && !(val & CPUCFG2_FP))
- /* FP should be set when enable LSX */
- ret = -EINVAL;
- else if ((val & CPUCFG2_LASX) && !(val & CPUCFG2_LSX))
- /* LSX, FP should be set when enable LASX, and FP has been checked before. */
- ret = -EINVAL;
- break;
+ if (!(val & CPUCFG2_LLFTP))
+ /* Guests must have a constant timer */
+ return -EINVAL;
+ if ((val & CPUCFG2_FP) && (!(val & CPUCFG2_FPSP) || !(val & CPUCFG2_FPDP)))
+ /* Single and double float point must both be set when FP is enabled */
+ return -EINVAL;
+ if ((val & CPUCFG2_LSX) && !(val & CPUCFG2_FP))
+ /* LSX architecturally implies FP but val does not satisfy that */
+ return -EINVAL;
+ if ((val & CPUCFG2_LASX) && !(val & CPUCFG2_LSX))
+ /* LASX architecturally implies LSX and FP but val does not satisfy that */
+ return -EINVAL;
+ return 0;
default:
- break;
+ /*
+ * Values for the other CPUCFG IDs are not being further validated
+ * besides the mask check above.
+ */
+ return 0;
}
- return ret;
}
static int kvm_get_one_reg(struct kvm_vcpu *vcpu,
@@ -566,7 +565,7 @@ static int kvm_loongarch_get_cpucfg_attr(struct kvm_vcpu *vcpu,
uint64_t val;
uint64_t __user *uaddr = (uint64_t __user *)attr->addr;
- ret = _kvm_get_cpucfg(attr->attr, &val);
+ ret = _kvm_get_cpucfg_mask(attr->attr, &val);
if (ret)
return ret;