Commit 156bffdb authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: Add a dedicated API for setting KVM-internal memslots 



Add a dedicated API for setting internal memslots, and have it explicitly
disallow setting userspace memslots.  Setting a userspace memslots without
a direct command from userspace would result in all manner of issues.

No functional change intended.

Cc: Tao Su <tao1.su@linux.intel.com>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: default avatarXiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: default avatarClaudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: default avatarChristoph Schlameuss <schlameuss@linux.ibm.com>
Link: https://lore.kernel.org/r/20250111002022.1230573-4-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent d131f004

arch/x86/kvm/x86.c

+1 −1
Original line number Diff line number Diff line
@@ -12827,7 +12827,7 @@ void __user * __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, 
		m.guest_phys_addr = gpa;

		m.userspace_addr = hva;

		m.memory_size = size;

		r = __kvm_set_memory_region(kvm, &m);

		r = kvm_set_internal_memslot(kvm, &m);

		if (r < 0)

			return ERR_PTR_USR(r);

	}

include/linux/kvm_host.h

+2 −2
Original line number Diff line number Diff line
@@ -1192,7 +1192,7 @@ enum kvm_mr_change { 
	KVM_MR_FLAGS_ONLY,

};



int __kvm_set_memory_region(struct kvm *kvm,

int kvm_set_internal_memslot(struct kvm *kvm,

			     const struct kvm_userspace_memory_region2 *mem);

void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot);

void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen);

virt/kvm/kvm_main.c

+12 −3
Original line number Diff line number Diff line
@@ -1926,7 +1926,7 @@ static bool kvm_check_memslot_overlap(struct kvm_memslots *slots, int id, 
	return false;

}



int __kvm_set_memory_region(struct kvm *kvm,

static int __kvm_set_memory_region(struct kvm *kvm,

				   const struct kvm_userspace_memory_region2 *mem)

{

	struct kvm_memory_slot *old, *new;
@@ -2050,7 +2050,16 @@ int __kvm_set_memory_region(struct kvm *kvm, 
	kfree(new);

	return r;

}

EXPORT_SYMBOL_GPL(__kvm_set_memory_region);



int kvm_set_internal_memslot(struct kvm *kvm,

			     const struct kvm_userspace_memory_region2 *mem)

{

	if (WARN_ON_ONCE(mem->slot < KVM_USER_MEM_SLOTS))

		return -EINVAL;



	return __kvm_set_memory_region(kvm, mem);

}

EXPORT_SYMBOL_GPL(kvm_set_internal_memslot);



static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,

					  struct kvm_userspace_memory_region2 *mem)