Commit f4debb40 authored by David Hildenbrand's avatar David Hildenbrand Committed by Christian Borntraeger
Browse files

s390/mm: take ipte_lock during shadow faults 



Let's take the ipte_lock while working on guest 2 provided page table, just
like the other gaccess functions.

Acked-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: default avatarDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
parent 7a674157

arch/s390/kvm/gaccess.c

+10 −1
Original line number Diff line number Diff line
@@ -1073,6 +1073,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, 


/**

 * kvm_s390_shadow_fault - handle fault on a shadow page table

 * @vcpu: virtual cpu

 * @sg: pointer to the shadow guest address space structure

 * @saddr: faulting address in the shadow gmap

 *
@@ -1082,7 +1083,8 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, 
 *	    - -EFAULT when accessing invalid guest addresses

 *	    - -ENOMEM if out of memory

 */

int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr)

int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg,

			  unsigned long saddr)

{

	union vaddress vaddr;

	union page_table_entry pte;
@@ -1091,6 +1093,12 @@ int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr) 
	int rc;



	down_read(&sg->mm->mmap_sem);

	/*

	 * We don't want any guest-2 tables to change - so the parent

	 * tables/pointers we read stay valid - unshadowing is however

	 * always possible - only guest_table_lock protects us.

	 */

	ipte_lock(vcpu);



	rc = gmap_shadow_pgt_lookup(sg, saddr, &pgt, &dat_protection);

	if (rc)
@@ -1105,6 +1113,7 @@ int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr) 
		rc = PGM_TRANSLATION_SPEC;

	if (!rc)

		rc = gmap_shadow_page(sg, saddr, __pte(pte.val));

	ipte_unlock(vcpu);

	up_read(&sg->mm->mmap_sem);

	return rc;

}

arch/s390/kvm/gaccess.h

+2 −1
Original line number Diff line number Diff line
@@ -361,6 +361,7 @@ void ipte_unlock(struct kvm_vcpu *vcpu); 
int ipte_lock_held(struct kvm_vcpu *vcpu);

int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra);



int kvm_s390_shadow_fault(struct gmap *shadow, unsigned long saddr);

int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *shadow,

			  unsigned long saddr);



#endif /* __KVM_S390_GACCESS_H */