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Signed-off-by: Carlos L=C3=B3pez --- arch/x86/kvm/svm/sev.c | 31 ++++++++++++------------------- 1 file changed, 12 insertions(+), 19 deletions(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index f59c65abe3cf..59a0ad3e0917 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -2367,7 +2367,6 @@ static int snp_launch_update(struct kvm *kvm, struct = kvm_sev_cmd *argp) struct kvm_memory_slot *memslot; long npages, count; void __user *src; - int ret =3D 0; =20 if (!sev_snp_guest(kvm) || !sev->snp_context) return -EINVAL; @@ -2407,13 +2406,11 @@ static int snp_launch_update(struct kvm *kvm, struc= t kvm_sev_cmd *argp) * initial expected state and better guard against unexpected * situations. */ - mutex_lock(&kvm->slots_lock); + guard(mutex)(&kvm->slots_lock); =20 memslot =3D gfn_to_memslot(kvm, params.gfn_start); - if (!kvm_slot_has_gmem(memslot)) { - ret =3D -EINVAL; - goto out; - } + if (!kvm_slot_has_gmem(memslot)) + return -EINVAL; =20 sev_populate_args.sev_fd =3D argp->sev_fd; sev_populate_args.type =3D params.type; @@ -2425,22 +2422,18 @@ static int snp_launch_update(struct kvm *kvm, struc= t kvm_sev_cmd *argp) argp->error =3D sev_populate_args.fw_error; pr_debug("%s: kvm_gmem_populate failed, ret %ld (fw_error %d)\n", __func__, count, argp->error); - ret =3D -EIO; - } else { - params.gfn_start +=3D count; - params.len -=3D count * PAGE_SIZE; - if (params.type !=3D KVM_SEV_SNP_PAGE_TYPE_ZERO) - params.uaddr +=3D count * PAGE_SIZE; - - ret =3D 0; - if (copy_to_user(u64_to_user_ptr(argp->data), ¶ms, sizeof(params))) - ret =3D -EFAULT; + return -EIO; } =20 -out: - mutex_unlock(&kvm->slots_lock); + params.gfn_start +=3D count; + params.len -=3D count * PAGE_SIZE; + if (params.type !=3D KVM_SEV_SNP_PAGE_TYPE_ZERO) + params.uaddr +=3D count * PAGE_SIZE; =20 - return ret; + if (copy_to_user(u64_to_user_ptr(argp->data), ¶ms, sizeof(params))) + return -EFAULT; + + return 0; } =20 static int snp_launch_update_vmsa(struct kvm *kvm, struct kvm_sev_cmd *arg= p) --=20 2.51.0