diff mbox series

[v2,1/1] KVM: s390: VSIE: sort out virtual/physical address in pin_guest_page

Message ID 20221025082039.117372-2-nrb@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series KVM: s390: VSIE: sort out virtual/physical address in pin_guest_page | expand

Commit Message

Nico Boehr Oct. 25, 2022, 8:20 a.m. UTC
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(-)

Comments

Christian Borntraeger Oct. 25, 2022, 8:34 a.m. UTC | #1
Am 25.10.22 um 10:20 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>

Looks good.
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>


Adding David CC.

> ---
>   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..0e9d020d7093 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 = phys_to_virt(hpa);
>   	return 0;
>   }
>
David Hildenbrand Oct. 25, 2022, 9:08 a.m. UTC | #2
On 25.10.22 10:34, Christian Borntraeger wrote:
> 
> 
> Am 25.10.22 um 10:20 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>
> 
> Looks good.
> Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
> 
> 
> Adding David CC.
> 
>> ---
>>    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..0e9d020d7093 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 = phys_to_virt(hpa);
>>    	return 0;

Right, we don't provide the scb to the SIE, but only read/write manually 
from it.

Acked-by: David Hildenbrand <david@redhat.com>
Claudio Imbrenda Oct. 25, 2022, 11:09 a.m. UTC | #3
On Tue, 25 Oct 2022 10:20:39 +0200
Nico Boehr <nrb@linux.ibm.com> wrote:

> 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>

Reviewed-by: Claudio Imbrenda <imbrenda@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..0e9d020d7093 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 = phys_to_virt(hpa);
>  	return 0;
>  }
>
diff mbox series

Patch

diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 94138f8f0c1c..0e9d020d7093 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 = phys_to_virt(hpa);
 	return 0;
 }