diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h
index 0a4fcb2800..b5beb7f90e 100644
--- a/include/hw/cxl/cxl_device.h
+++ b/include/hw/cxl/cxl_device.h
@@ -397,6 +397,11 @@ static inline void __toggle_media(CXLDeviceState *cxl_dstate, int val)
 #define cxl_dev_enable_media(cxlds)                     \
         do { __toggle_media((cxlds), 0x1); } while (0)
 
+static inline bool scan_media_running(CXLCCI *cci)
+{
+    return !!cci->bg.runtime && cci->bg.opcode == 0x4304;
+}
+
 static inline bool sanitize_running(CXLCCI *cci)
 {
     return !!cci->bg.runtime && cci->bg.opcode == 0x4400;
@@ -491,6 +496,9 @@ struct CXLType3Dev {
     unsigned int poison_list_cnt;
     bool poison_list_overflowed;
     uint64_t poison_list_overflow_ts;
+    /* Poison Injection - backup */
+    CXLPoisonList poison_list_bkp;
+    CXLPoisonList scan_media_results;
 
     struct dynamic_capacity {
         HostMemoryBackend *host_dc;
@@ -558,6 +566,7 @@ CXLRetCode cxl_event_clear_records(CXLDeviceState *cxlds,
 void cxl_event_irq_assert(CXLType3Dev *ct3d);
 
 void cxl_set_poison_list_overflowed(CXLType3Dev *ct3d);
+void cxl_clear_poison_list_overflowed(CXLType3Dev *ct3d);
 
 CXLDCRegion *cxl_find_dc_region(CXLType3Dev *ct3d, uint64_t dpa, uint64_t len);
 
diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
index facec42dc8..8ae9c6a699 100644
--- a/hw/cxl/cxl-mailbox-utils.c
+++ b/hw/cxl/cxl-mailbox-utils.c
@@ -83,6 +83,8 @@ enum {
         #define GET_POISON_LIST        0x0
         #define INJECT_POISON          0x1
         #define CLEAR_POISON           0x2
+        #define GET_SCAN_MEDIA_CAPABILITIES 0x3
+        #define SCAN_MEDIA             0x4
     DCD_CONFIG  = 0x48,
         #define GET_DC_CONFIG          0x0
         #define GET_DYN_CAP_EXT_LIST   0x1
@@ -1110,6 +1112,10 @@ static CXLRetCode cmd_media_get_poison_list(const struct cxl_cmd *cmd,
         out->flags = (1 << 1);
         stq_le_p(&out->overflow_timestamp, ct3d->poison_list_overflow_ts);
     }
+    if (scan_media_running(cci)) {
+        out->flags |= (1 << 2);
+    }
+
     stw_le_p(&out->count, record_count);
     *len_out = out_pl_len;
     return CXL_MBOX_SUCCESS;
@@ -1139,6 +1145,16 @@ static CXLRetCode cmd_media_inject_poison(const struct cxl_cmd *cmd,
             return CXL_MBOX_SUCCESS;
         }
     }
+    /*
+     * Freeze the list if there is an on-going scan media operation.
+     */
+    if (scan_media_running(cci)) {
+        /*
+         * XXX: Spec is ambiguous - is this case considered
+         * a successful return despite not adding to the list?
+         */
+        goto success;
+    }
 
     if (ct3d->poison_list_cnt == CXL_POISON_LIST_LIMIT) {
         return CXL_MBOX_INJECT_POISON_LIMIT;
@@ -1154,6 +1170,7 @@ static CXLRetCode cmd_media_inject_poison(const struct cxl_cmd *cmd,
      */
     QLIST_INSERT_HEAD(poison_list, p, node);
     ct3d->poison_list_cnt++;
+success:
     *len_out = 0;
 
     return CXL_MBOX_SUCCESS;
@@ -1193,6 +1210,17 @@ static CXLRetCode cmd_media_clear_poison(const struct cxl_cmd *cmd,
         }
     }
 
+    /*
+     * Freeze the list if there is an on-going scan media operation.
+     */
+    if (scan_media_running(cci)) {
+        /*
+         * XXX: Spec is ambiguous - is this case considered
+         * a successful return despite not removing from the list?
+         */
+        goto success;
+    }
+
     QLIST_FOREACH(ent, poison_list, node) {
         /*
          * Test for contained in entry. Simpler than general case
@@ -1203,7 +1231,7 @@ static CXLRetCode cmd_media_clear_poison(const struct cxl_cmd *cmd,
         }
     }
     if (!ent) {
-        return CXL_MBOX_SUCCESS;
+        goto success;
     }
 
     QLIST_REMOVE(ent, node);
@@ -1240,11 +1268,180 @@ static CXLRetCode cmd_media_clear_poison(const struct cxl_cmd *cmd,
     }
     /* Any fragments have been added, free original entry */
     g_free(ent);
+success:
     *len_out = 0;
 
     return CXL_MBOX_SUCCESS;
 }
 
+/*
+ * CXL r3.1 section 8.2.9.9.4.4: Get Scan Media Capabilities
+ */
+static CXLRetCode
+cmd_media_get_scan_media_capabilities(const struct cxl_cmd *cmd,
+                                      uint8_t *payload_in,
+                                      size_t len_in,
+                                      uint8_t *payload_out,
+                                      size_t *len_out,
+                                      CXLCCI *cci)
+{
+    struct get_scan_media_capabilities_pl {
+        uint64_t pa;
+        uint64_t length;
+    } QEMU_PACKED;
+
+    struct get_scan_media_capabilities_out_pl {
+        uint32_t estimated_runtime_ms;
+    };
+
+    CXLType3Dev *ct3d = CXL_TYPE3(cci->d);
+    CXLDeviceState *cxl_dstate = &ct3d->cxl_dstate;
+    struct get_scan_media_capabilities_pl *in = (void *)payload_in;
+    struct get_scan_media_capabilities_out_pl *out = (void *)payload_out;
+    uint64_t query_start;
+    uint64_t query_length;
+
+    query_start = ldq_le_p(&in->pa);
+    /* 64 byte alignment required */
+    if (query_start & 0x3f) {
+        return CXL_MBOX_INVALID_INPUT;
+    }
+    query_length = ldq_le_p(&in->length) * CXL_CACHE_LINE_SIZE;
+
+    if (query_start + query_length > cxl_dstate->static_mem_size) {
+        return CXL_MBOX_INVALID_PA;
+    }
+
+    /*
+     * Just use 400 nanosecond access/read latency + 100 ns for
+     * the cost of updating the poison list. For small enough
+     * chunks return at least 1 ms.
+     */
+    stl_le_p(&out->estimated_runtime_ms,
+             MAX(1, query_length * (0.0005L / 64)));
+
+    *len_out = sizeof(*out);
+    return CXL_MBOX_SUCCESS;
+}
+
+static void __do_scan_media(CXLType3Dev *ct3d)
+{
+    CXLPoison *ent;
+    unsigned int results_cnt = 0;
+
+    QLIST_FOREACH(ent, &ct3d->scan_media_results, node) {
+        results_cnt++;
+    }
+
+    /* only scan media may clear the overflow */
+    if (ct3d->poison_list_overflowed &&
+        ct3d->poison_list_cnt == results_cnt) {
+        cxl_clear_poison_list_overflowed(ct3d);
+    }
+}
+
+/*
+ * CXL r3.1 section 8.2.9.9.4.5: Scan Media
+ */
+static CXLRetCode cmd_media_scan_media(const struct cxl_cmd *cmd,
+                                       uint8_t *payload_in,
+                                       size_t len_in,
+                                       uint8_t *payload_out,
+                                       size_t *len_out,
+                                       CXLCCI *cci)
+{
+    struct scan_media_pl {
+        uint64_t pa;
+        uint64_t length;
+        uint8_t flags;
+    } QEMU_PACKED;
+
+    struct scan_media_pl *in = (void *)payload_in;
+    CXLType3Dev *ct3d = CXL_TYPE3(cci->d);
+    CXLDeviceState *cxl_dstate = &ct3d->cxl_dstate;
+    uint64_t query_start;
+    uint64_t query_length;
+    CXLPoison *ent, *next;
+
+    query_start = ldq_le_p(&in->pa);
+    /* 64 byte alignment required */
+    if (query_start & 0x3f) {
+        return CXL_MBOX_INVALID_INPUT;
+    }
+    query_length = ldq_le_p(&in->length) * CXL_CACHE_LINE_SIZE;
+
+    if (query_start + query_length > cxl_dstate->static_mem_size) {
+        return CXL_MBOX_INVALID_PA;
+    }
+    if (ct3d->dc.num_regions && query_start + query_length >=
+            cxl_dstate->static_mem_size + ct3d->dc.total_capacity) {
+        return CXL_MBOX_INVALID_PA;
+    }
+
+    if (in->flags == 0) { /* TODO */
+        qemu_log_mask(LOG_UNIMP,
+                      "Scan Media Event Log is unsupported\n");
+    }
+
+    /* any previous results are discarded upon a new Scan Media */
+    QLIST_FOREACH_SAFE(ent, &ct3d->scan_media_results, node, next) {
+        QLIST_REMOVE(ent, node);
+        g_free(ent);
+    }
+
+    /* kill the poison list - it will be recreated */
+    if (ct3d->poison_list_overflowed) {
+        QLIST_FOREACH_SAFE(ent, &ct3d->poison_list, node, next) {
+            QLIST_REMOVE(ent, node);
+            g_free(ent);
+            ct3d->poison_list_cnt--;
+        }
+    }
+
+    /*
+     * Scan the backup list and move corresponding entries
+     * into the results list, updating the poison list
+     * when possible.
+     */
+    QLIST_FOREACH_SAFE(ent, &ct3d->poison_list_bkp, node, next) {
+        CXLPoison *res;
+
+        if (ent->start >= query_start + query_length ||
+            ent->start + ent->length <= query_start) {
+            continue;
+        }
+
+        /*
+         * If a Get Poison List cmd comes in while this
+         * scan is being done, it will see the new complete
+         * list, while setting the respective flag.
+         */
+        if (ct3d->poison_list_cnt < CXL_POISON_LIST_LIMIT) {
+            CXLPoison *p = g_new0(CXLPoison, 1);
+
+            p->start = ent->start;
+            p->length = ent->length;
+            p->type = ent->type;
+            QLIST_INSERT_HEAD(&ct3d->poison_list, p, node);
+            ct3d->poison_list_cnt++;
+        }
+
+        res = g_new0(CXLPoison, 1);
+        res->start = ent->start;
+        res->length = ent->length;
+        res->type = ent->type;
+        QLIST_INSERT_HEAD(&ct3d->scan_media_results, res, node);
+
+        QLIST_REMOVE(ent, node);
+        g_free(ent);
+    }
+
+    cci->bg.runtime = MAX(1, query_length * (0.0005L / 64));
+    *len_out = 0;
+
+    return CXL_MBOX_BG_STARTED;
+}
+
 /*
  * CXL r3.1 section 8.2.9.9.9.1: Get Dynamic Capacity Configuration
  * (Opcode: 4800h)
@@ -1857,6 +2054,11 @@ static const struct cxl_cmd cxl_cmd_set[256][256] = {
         cmd_media_inject_poison, 8, 0 },
     [MEDIA_AND_POISON][CLEAR_POISON] = { "MEDIA_AND_POISON_CLEAR_POISON",
         cmd_media_clear_poison, 72, 0 },
+    [MEDIA_AND_POISON][GET_SCAN_MEDIA_CAPABILITIES] = {
+        "MEDIA_AND_POISON_GET_SCAN_MEDIA_CAPABILITIES",
+        cmd_media_get_scan_media_capabilities, 16, 0 },
+    [MEDIA_AND_POISON][SCAN_MEDIA] = { "MEDIA_AND_POISON_SCAN_MEDIA",
+        cmd_media_scan_media, 17, BACKGROUND_OPERATION },
 };
 
 static const struct cxl_cmd cxl_cmd_set_dcd[256][256] = {
@@ -1988,8 +2190,13 @@ static void bg_timercb(void *opaque)
             cxl_dev_enable_media(&ct3d->cxl_dstate);
         }
         break;
-        case 0x4304: /* TODO: scan media */
+        case 0x4304: /* scan media */
+        {
+            CXLType3Dev *ct3d = CXL_TYPE3(cci->d);
+
+            __do_scan_media(ct3d);
             break;
+        }
         default:
             __builtin_unreachable();
             break;
diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c
index e7fbbb4d51..e763b9bff0 100644
--- a/hw/mem/cxl_type3.c
+++ b/hw/mem/cxl_type3.c
@@ -1319,6 +1319,12 @@ void cxl_set_poison_list_overflowed(CXLType3Dev *ct3d)
             cxl_device_get_timestamp(&ct3d->cxl_dstate);
 }
 
+void cxl_clear_poison_list_overflowed(CXLType3Dev *ct3d)
+{
+    ct3d->poison_list_overflowed = false;
+    ct3d->poison_list_overflow_ts = 0;
+}
+
 void qmp_cxl_inject_poison(const char *path, uint64_t start, uint64_t length,
                            Error **errp)
 {
@@ -1355,19 +1361,21 @@ void qmp_cxl_inject_poison(const char *path, uint64_t start, uint64_t length,
         }
     }
 
-    if (ct3d->poison_list_cnt == CXL_POISON_LIST_LIMIT) {
-        cxl_set_poison_list_overflowed(ct3d);
-        return;
-    }
-
     p = g_new0(CXLPoison, 1);
     p->length = length;
     p->start = start;
     /* Different from injected via the mbox */
     p->type = CXL_POISON_TYPE_INTERNAL;
 
-    QLIST_INSERT_HEAD(&ct3d->poison_list, p, node);
-    ct3d->poison_list_cnt++;
+    if (ct3d->poison_list_cnt < CXL_POISON_LIST_LIMIT) {
+        QLIST_INSERT_HEAD(&ct3d->poison_list, p, node);
+        ct3d->poison_list_cnt++;
+    } else {
+        if (!ct3d->poison_list_overflowed) {
+            cxl_set_poison_list_overflowed(ct3d);
+        }
+        QLIST_INSERT_HEAD(&ct3d->poison_list_bkp, p, node);
+    }
 }
 
 /* For uncorrectable errors include support for multiple header recording */
