diff --git a/Drivers/BSP/GD5F2GQ5UE/nand_ftl.c b/Drivers/BSP/GD5F2GQ5UE/nand_ftl.c
index 995f811a..f7ed20f7 100644
--- a/Drivers/BSP/GD5F2GQ5UE/nand_ftl.c
+++ b/Drivers/BSP/GD5F2GQ5UE/nand_ftl.c
@@ -52,6 +52,9 @@ static uint8_t                s_copy_buf[FTL_PAGE_SIZE];
 /* 初始化状态 */
 static uint8_t                s_initialized;
 
+/* resume 搜索探针日志窗口（诊断：逐探测记录判定输入） */
+static uint8_t                s_probe_log;
+
 /* ======================== 私有函数声明 ======================== */
 
 static int ftl_flush_cache(void);
@@ -94,7 +97,12 @@ static int ftl_read_page(dhara_sector_t lpn) {
 
 int dhara_nand_is_bad(const struct dhara_nand *n, dhara_block_t b) {
     (void)n;
-    return gd5f2gq5ue_is_block_bad(ftl_phy_block(b));
+    const int bad = gd5f2gq5ue_is_block_bad(ftl_phy_block(b));
+    if (s_probe_log) {
+        DBG_INFO("probe blk %lu: bbt_bad=%u", (unsigned long)b,
+                 (unsigned int)bad);
+    }
+    return bad;
 }
 
 void dhara_nand_mark_bad(const struct dhara_nand *n, dhara_block_t b) {
@@ -187,18 +195,42 @@ int dhara_nand_is_free(const struct dhara_nand *n, dhara_page_t p) {
 int dhara_nand_read(const struct dhara_nand *n, dhara_page_t p, size_t offset, size_t length, uint8_t *data, dhara_error_t *err) {
     (void)n;
     uint32_t phy_pg = ftl_phy_page(p);
+    int rret;
+    int eret;
 
-    if (gd5f_page_read(phy_pg) != GD5F_OK) {
+    if ((rret = gd5f_page_read(phy_pg)) != GD5F_OK) {
+        if (s_probe_log) {
+            DBG_INFO("probe pg %lu blk %lu: page_read=%d",
+                     (unsigned long)phy_pg, (unsigned long)(p >> 6),
+                     rret);
+        }
         dhara_set_error(err, DHARA_E_ECC);
         return -1;
     }
 
-    if (gd5f_check_ecc() != GD5F_OK) {
+    if ((eret = gd5f_check_ecc()) != GD5F_OK) {
+        if (s_probe_log) {
+            DBG_INFO("probe pg %lu blk %lu: ecc=%d",
+                     (unsigned long)phy_pg, (unsigned long)(p >> 6),
+                     eret);
+        }
         dhara_set_error(err, DHARA_E_ECC);
         return -1;
     }
 
     gd5f_read_from_cache((uint16_t)offset, data, length);
+
+    if (s_probe_log && offset == 0 && length == FTL_PAGE_SIZE) {
+        /* 组末页（组内偏移 15）= checkpoint 页：记录 magic/epoch 判定 */
+        if ((p & 63u) == 15u) {
+            const uint8_t *m = data;
+            DBG_INFO("probe pg %lu blk %lu chk: magic=%u epoch=%u",
+                     (unsigned long)phy_pg, (unsigned long)(p >> 6),
+                     (unsigned int)((m[0] == 'D' && m[1] == 'h' &&
+                                     m[2] == 'a') ? 1 : 0),
+                     (unsigned int)m[3]);
+        }
+    }
     return 0;
 }
 
@@ -248,6 +280,7 @@ DSTATUS disk_initialize(BYTE pdrv) {
 
     {
         dhara_error_t err;
+        s_probe_log = 1;
         if (dhara_map_resume(&s_map, &err) < 0) {
             DBG_INFO("No valid map found, creating fresh (err=%d)", err);
             dhara_map_clear(&s_map);
@@ -255,6 +288,7 @@ DSTATUS disk_initialize(BYTE pdrv) {
             DBG_INFO("Map resumed: %lu/%lu sectors used",
                      dhara_map_size(&s_map), dhara_map_capacity(&s_map));
         }
+        s_probe_log = 0;
     }
 
     s_initialized = 1;