Index: sys/dev/nvme/nvme.h
===================================================================
--- sys/dev/nvme/nvme.h
+++ sys/dev/nvme/nvme.h
@@ -614,7 +614,7 @@
 	uint32_t cdw13;		/* command-specific */
 	uint32_t cdw14;		/* command-specific */
 	uint32_t cdw15;		/* command-specific */
-} __packed;
+};
 
 _Static_assert(sizeof(struct nvme_command) == 16 * 4, "bad size for nvme_command");
 
@@ -632,7 +632,7 @@
 	/* dword 3 */
 	uint16_t		cid;	/* command identifier */
 	uint16_t		status;
-} __packed;
+} __aligned(16);
 
 _Static_assert(sizeof(struct nvme_completion) == 4 * 4, "bad size for nvme_completion");
 
@@ -640,7 +640,7 @@
 	uint32_t attributes;
 	uint32_t length;
 	uint64_t starting_lba;
-} __packed;
+} __aligned(16);
 
 /* Largest DSM Trim that can be done */
 #define NVME_MAX_DSM_TRIM		4096