On Jun  9 13:46, Heinrich Schuchardt wrote:
>The EUI64 field is the only identifier for NVMe namespaces in UEFI device
>paths. Add a new namespace property "eui64", that provides the user the
>option to specify the EUI64.
>
>Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
>---
> docs/system/nvme.rst |  4 +++
> hw/nvme/ctrl.c       | 58 ++++++++++++++++++++++++++------------------
> hw/nvme/ns.c         |  2 ++
> hw/nvme/nvme.h       |  1 +
> 4 files changed, 42 insertions(+), 23 deletions(-)
>
>diff --git a/docs/system/nvme.rst b/docs/system/nvme.rst
>index f7f63d6bf6..a6042f942a 100644
>--- a/docs/system/nvme.rst
>+++ b/docs/system/nvme.rst
>@@ -81,6 +81,10 @@ There are a number of parameters available:
>   Set the UUID of the namespace. This will be reported as a "Namespace UUID"
>   descriptor in the Namespace Identification Descriptor List.
>
>+``eui64``
>+  Set the EUI64 of the namespace. This will be reported as a "IEEE Extended
>+  Unique Identifier" descriptor in the Namespace Identification Descriptor List.
>+
> ``bus``
>   If there are more ``nvme`` devices defined, this parameter may be used to
>   attach the namespace to a specific ``nvme`` device (identified by an ``id``
>diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c
>index 0bcaf7192f..21f2d6843b 100644
>--- a/hw/nvme/ctrl.c
>+++ b/hw/nvme/ctrl.c
>@@ -4426,19 +4426,19 @@ static uint16_t nvme_identify_ns_descr_list(NvmeCtrl *n, NvmeRequest *req)
>     NvmeIdentify *c = (NvmeIdentify *)&req->cmd;
>     uint32_t nsid = le32_to_cpu(c->nsid);
>     uint8_t list[NVME_IDENTIFY_DATA_SIZE] = {};
>-
>-    struct data {
>-        struct {
>-            NvmeIdNsDescr hdr;
>-            uint8_t v[NVME_NIDL_UUID];
>-        } uuid;
>-        struct {
>-            NvmeIdNsDescr hdr;
>-            uint8_t v;
>-        } csi;
>-    };
>-
>-    struct data *ns_descrs = (struct data *)list;
>+    uint8_t *pos = list;
>+    struct {
>+        NvmeIdNsDescr hdr;
>+        uint8_t v[NVME_NIDL_UUID];
>+    } QEMU_PACKED uuid;
>+    struct {
>+        NvmeIdNsDescr hdr;
>+        uint64_t v;
>+    } QEMU_PACKED eui64;
>+    struct {
>+        NvmeIdNsDescr hdr;
>+        uint8_t v;
>+    } QEMU_PACKED csi;
>
>     trace_pci_nvme_identify_ns_descr_list(nsid);
>
>@@ -4452,17 +4452,29 @@ static uint16_t nvme_identify_ns_descr_list(NvmeCtrl *n, NvmeRequest *req)
>     }
>
>     /*
>-     * Because the NGUID and EUI64 fields are 0 in the Identify Namespace data
>-     * structure, a Namespace UUID (nidt = 3h) must be reported in the
>-     * Namespace Identification Descriptor. Add the namespace UUID here.
>+     * If the EUI64 field is 0 and the NGUID field is 0, the namespace must
>+     * provide a valid Namespace UUID in the Namespace Identification Descriptor
>+     * data structure. QEMU does not yet support setting NGUID.
>      */
>-    ns_descrs->uuid.hdr.nidt = NVME_NIDT_UUID;
>-    ns_descrs->uuid.hdr.nidl = NVME_NIDL_UUID;
>-    memcpy(&ns_descrs->uuid.v, ns->params.uuid.data, NVME_NIDL_UUID);
>-
>-    ns_descrs->csi.hdr.nidt = NVME_NIDT_CSI;
>-    ns_descrs->csi.hdr.nidl = NVME_NIDL_CSI;
>-    ns_descrs->csi.v = ns->csi;
>+    uuid.hdr.nidt = NVME_NIDT_UUID;
>+    uuid.hdr.nidl = NVME_NIDL_UUID;
>+    memcpy(uuid.v, ns->params.uuid.data, NVME_NIDL_UUID);
>+    memcpy(pos, &uuid, sizeof(uuid));
>+    pos += sizeof(uuid);
>+
>+    if (ns->params.eui64) {
>+        eui64.hdr.nidt = NVME_NIDT_EUI64;
>+        eui64.hdr.nidl = NVME_NIDL_EUI64;
>+        eui64.v = cpu_to_be64(ns->params.eui64);
>+        memcpy(pos, &eui64, sizeof(eui64));
>+        pos += sizeof(eui64);
>+    }
>+
>+    csi.hdr.nidt = NVME_NIDT_CSI;
>+    csi.hdr.nidl = NVME_NIDL_CSI;
>+    csi.v = ns->csi;
>+    memcpy(pos, &csi, sizeof(csi));
>+    pos += sizeof(csi);
>
>     return nvme_c2h(n, list, sizeof(list), req);
> }
>diff --git a/hw/nvme/ns.c b/hw/nvme/ns.c
>index 992e5a13f5..ddf395d60e 100644
>--- a/hw/nvme/ns.c
>+++ b/hw/nvme/ns.c
>@@ -77,6 +77,7 @@ static int nvme_ns_init(NvmeNamespace *ns, Error **errp)
>     id_ns->mssrl = cpu_to_le16(ns->params.mssrl);
>     id_ns->mcl = cpu_to_le32(ns->params.mcl);
>     id_ns->msrc = ns->params.msrc;
>+    id_ns->eui64 = cpu_to_be64(ns->params.eui64);
>
>     ds = 31 - clz32(ns->blkconf.logical_block_size);
>     ms = ns->params.ms;
>@@ -518,6 +519,7 @@ static Property nvme_ns_props[] = {
>     DEFINE_PROP_BOOL("shared", NvmeNamespace, params.shared, false),
>     DEFINE_PROP_UINT32("nsid", NvmeNamespace, params.nsid, 0),
>     DEFINE_PROP_UUID("uuid", NvmeNamespace, params.uuid),
>+    DEFINE_PROP_UINT64("eui64", NvmeNamespace, params.eui64, 0),
>     DEFINE_PROP_UINT16("ms", NvmeNamespace, params.ms, 0),
>     DEFINE_PROP_UINT8("mset", NvmeNamespace, params.mset, 0),
>     DEFINE_PROP_UINT8("pi", NvmeNamespace, params.pi, 0),
>diff --git a/hw/nvme/nvme.h b/hw/nvme/nvme.h
>index 81a35cda14..abe7fab21c 100644
>--- a/hw/nvme/nvme.h
>+++ b/hw/nvme/nvme.h
>@@ -83,6 +83,7 @@ typedef struct NvmeNamespaceParams {
>     bool     shared;
>     uint32_t nsid;
>     QemuUUID uuid;
>+    uint64_t eui64;
>
>     uint16_t ms;
>     uint8_t  mset;
>--
>2.30.2
>
>

Would it make sense to provide a sensible default for EUI64 such that it 
is always there? That is, using the same IEEE OUI as we already report 
in the IEEE field and add an extension identifier by grabbing 5 bytes 
from the UUID?