diff --git a/arch/x86/coco/sev/core.c b/arch/x86/coco/sev/core.c
index 068653865bfb..b0d423a353ab 100644
--- a/arch/x86/coco/sev/core.c
+++ b/arch/x86/coco/sev/core.c
@@ -2008,6 +2008,15 @@ int snp_send_guest_request(struct snp_msg_desc *mdesc, struct snp_guest_req *req
 	u64 seqno;
 	int rc;
 
+	/*
+	 * enc_payload() calls aesgcm_encrypt(), which can potentially offload to HW.
+	 * The offload's DMA SG list of data to encrypt has to be in linear mapping.
+	 */
+	if (!virt_addr_valid(req->req_buf) || !virt_addr_valid(req->resp_buf)) {
+		pr_warn("AES-GSM buffers must be in linear mapping");
+		return -EINVAL;
+	}
+
 	guard(mutex)(&snp_cmd_mutex);
 
 	/* Check if the VMPCK is not empty */