Commit ec5c8697 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: s390: Skip gfn/size sanity checks on memslot DELETE or FLAGS_ONLY 



Sanity check the hva, gfn, and size of a userspace memory region only if
any of those properties can change, i.e. skip the checks for DELETE and
FLAGS_ONLY.  KVM doesn't allow moving the hva or changing the size, a gfn
change shows up as a MOVE even if flags are being modified, and the
checks are pointless for the DELETE case as userspace_addr and gfn_base
are zeroed by common KVM.

No functional change intended.

Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Signed-off-by: default avatarMaciej S. Szmigiero <maciej.szmigiero@oracle.com>
Message-Id: <05430738437ac2c9c7371ac4e11f4a533e1677da.1638817640.git.maciej.szmigiero@oracle.com>
parent 77aedf26

arch/s390/kvm/kvm-s390.c

+9 −4
Original line number Diff line number Diff line
@@ -5011,7 +5011,14 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm, 
				   struct kvm_memory_slot *new,

				   enum kvm_mr_change change)

{

	gpa_t size = new->npages * PAGE_SIZE;

	gpa_t size;



	/* When we are protected, we should not change the memory slots */

	if (kvm_s390_pv_get_handle(kvm))

		return -EINVAL;



	if (change == KVM_MR_DELETE || change == KVM_MR_FLAGS_ONLY)

		return 0;



	/* A few sanity checks. We can have memory slots which have to be

	   located/ended at a segment boundary (1MB). The memory in userland is
@@ -5021,15 +5028,13 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm, 
	if (new->userspace_addr & 0xffffful)

		return -EINVAL;



	size = new->npages * PAGE_SIZE;

	if (size & 0xffffful)

		return -EINVAL;



	if ((new->base_gfn * PAGE_SIZE) + size > kvm->arch.mem_limit)

		return -EINVAL;



	/* When we are protected, we should not change the memory slots */

	if (kvm_s390_pv_get_handle(kvm))

		return -EINVAL;

	return 0;

}