[PATCH 1/2] KVM: selftests: Cast guest_memfd fd to a signed int when checking for >= 0

[Sean Christopherson <seanjc@google.com>]

When conditionally closing a memory region's guest_memfd file descriptor,
cast the field to a signed it so that negative values are correctly
detected.  Because selftests reuse "struct kvm_userspace_memory_region2"
instead of providing custom storage, they pick up the kernel uAPI's __u32
definition of the file descriptor, not the more common "int" definition,
e.g. that's used for userspace_mem_region.fd.

Fixes: bb2968ad6c33 ("KVM: selftests: Add support for creating private memslots")
Reported-by: Bibo Mao <maobibo@loongson.cn>
Closes: https://lore.kernel.org/all/20260508015013.4108345-1-maobibo@loongson.cn
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 tools/testing/selftests/kvm/lib/kvm_util.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index e08967ef7b7b..4ad015c6c44f 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -817,7 +817,7 @@ static void __vm_mem_region_delete(struct kvm_vm *vm,
 		kvm_munmap(region->mmap_alias, region->mmap_size);
 		close(region->fd);
 	}
-	if (region->region.guest_memfd >= 0)
+	if ((int)region->region.guest_memfd >= 0)
 		close(region->region.guest_memfd);
 
 	free(region);
-- 
2.54.0.794.g4f17f83d09-goog