| Message ID | 20221024160237.33912-1-nrb@linux.ibm.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v1] KVM: s390: VSIE: sort out virtual/physical address in pin_guest_page | expand |
Am 24.10.22 um 18:02 schrieb Nico Boehr: > pin_guest_page() used page_to_virt() to calculate the hpa of the pinned > page. This currently works, because virtual and physical addresses are > the same. Use page_to_phys() instead to resolve the virtual-real address > confusion. > > One caller of pin_guest_page() actually expected the hpa to be a hva, so > add the missing phys_to_virt() conversion here. > > Signed-off-by: Nico Boehr <nrb@linux.ibm.com> > --- > arch/s390/kvm/vsie.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c > index 94138f8f0c1c..c6a10ff46d58 100644 > --- a/arch/s390/kvm/vsie.c > +++ b/arch/s390/kvm/vsie.c > @@ -654,7 +654,7 @@ static int pin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t *hpa) > page = gfn_to_page(kvm, gpa_to_gfn(gpa)); > if (is_error_page(page)) > return -EINVAL; > - *hpa = (hpa_t) page_to_virt(page) + (gpa & ~PAGE_MASK); > + *hpa = (hpa_t)page_to_phys(page) + (gpa & ~PAGE_MASK); > return 0; > } > > @@ -869,7 +869,7 @@ static int pin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, > WARN_ON_ONCE(rc); > return 1; > } > - vsie_page->scb_o = (struct kvm_s390_sie_block *) hpa; > + vsie_page->scb_o = (struct kvm_s390_sie_block *)phys_to_virt(hpa); Do we still need the cast here? phys_to_virt should return a void * and the assignment should succeed. > return 0; > } >
Quoting Christian Borntraeger (2022-10-25 08:37:21) [...] > > diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c > > index 94138f8f0c1c..c6a10ff46d58 100644 [...] > > @@ -869,7 +869,7 @@ static int pin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, > > WARN_ON_ONCE(rc); > > return 1; > > } > > - vsie_page->scb_o = (struct kvm_s390_sie_block *) hpa; > > + vsie_page->scb_o = (struct kvm_s390_sie_block *)phys_to_virt(hpa); > > Do we still need the cast here? phys_to_virt should return a void * and the assignment should succeed. Yes, right. Fixed in v2.
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c index 94138f8f0c1c..c6a10ff46d58 100644 --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -654,7 +654,7 @@ static int pin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t *hpa) page = gfn_to_page(kvm, gpa_to_gfn(gpa)); if (is_error_page(page)) return -EINVAL; - *hpa = (hpa_t) page_to_virt(page) + (gpa & ~PAGE_MASK); + *hpa = (hpa_t)page_to_phys(page) + (gpa & ~PAGE_MASK); return 0; } @@ -869,7 +869,7 @@ static int pin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, WARN_ON_ONCE(rc); return 1; } - vsie_page->scb_o = (struct kvm_s390_sie_block *) hpa; + vsie_page->scb_o = (struct kvm_s390_sie_block *)phys_to_virt(hpa); return 0; }
pin_guest_page() used page_to_virt() to calculate the hpa of the pinned page. This currently works, because virtual and physical addresses are the same. Use page_to_phys() instead to resolve the virtual-real address confusion. One caller of pin_guest_page() actually expected the hpa to be a hva, so add the missing phys_to_virt() conversion here. Signed-off-by: Nico Boehr <nrb@linux.ibm.com> --- arch/s390/kvm/vsie.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)