source code:
 11 __attribute__ ((__section__(".init.data"))) uint32_t fw_ver = 0;

 20 struct spinlock {
 21         uint32_t lock;
 22 }__attribute__((packed));

 78 __attribute__ ((__section__(".init.data"))) spinlock_t dbg_lock = {.lock = 0};
 79 __attribute__ ((__section__(".init.data"))) uint32_t dbg_rd_idx = 0;

ldscript:
153 SECTIONS {
154 .init.data : {
155
156 } > INIT_DATA
157 }

system.map:
482  .init.data     0x000000000003fc00       0x10
483                 0x000000000003fc00                fw_ver
484                 0x000000000003fc08                dbg_lock
485                 0x000000000003fc0c                dbg_rd_idx