On 08/30/2017 06:06 PM, David Hildenbrand wrote:
> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
> ---
> arch/s390/kvm/vsie.c | 19 +++++--------------
> include/linux/kvm_host.h | 1 +
> virt/kvm/kvm_main.c | 4 ++--
> 3 files changed, 8 insertions(+), 16 deletions(-)
>
> diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
> index b5eec30eb37d..a21763b4c229 100644
> --- a/arch/s390/kvm/vsie.c
> +++ b/arch/s390/kvm/vsie.c
> @@ -445,17 +445,12 @@ static int map_prefix(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
> static int pin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t *hpa)
> {
> struct page *page;
> - hva_t hva;
> - int rc;
>
> - hva = gfn_to_hva(kvm, gpa_to_gfn(gpa));
> - if (kvm_is_error_hva(hva))
> - return -EINVAL;
> - rc = get_user_pages_fast(hva, 1, 1, &page);
> - if (rc < 0)
> - return rc;
> - else if (rc != 1)
> + page = gfn_to_page(kvm, gpa_to_gfn(gpa));
> + if (PTR_ERR(page) == -ENOMEM)
> return -ENOMEM;
Can this actually happen? Reading gfn_to_page does not seem
to have a path that returns ENOMEM.
> + if (is_error_page(page))
> + return -EINVAL;
So just this might be enough? Most other users of gfn_to_page only check
for is_error_page (but not for ENOMEM).
