我有一张 8GB 的 SD 卡，用于扩展我的 Android 手机的存储空间。现在在 Android 或 Windows 上都检测不到它。Ubuntu 可以显示它，但无法格式化或删除分区，我尝试了其他问题中的解决方案。
这是 sudo fdisk -l /dev/mmcblk0 的输出
ubuntu@ubuntu:~$ sudo fdisk -l /dev/mmcblk0
Disk /dev/mmcblk0: 7.4 GiB, 7948206080 bytes, 15523840 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 321960E8-BABE-4EF1-907A-84F301351CAA
Device Start End Sectors Size Type
/dev/mmcblk0p1 2048 34815 32768 16M unknown
/dev/mmcblk0p2 34816 15523806 15488991 7.4G unknown
当我尝试格式化或删除分区时，磁盘和 gpart 显示操作成功，但它没有反映，只是显示分区为未知
https://i.stack.imgur.com/sm9CH.png
https://i.stack.imgur.com/Ob5CN.png
我尝试过 dd 命令的变体
ubuntu@ubuntu:~$ sudo dd if=/dev/zero of=/dev/mmcblk0p1 bs=2048 count=32
32+0 records in
32+0 records out
65536 bytes (66 kB, 64 KiB) copied, 0.311052 s, 211 kB/s
ubuntu@ubuntu:~$ sudo dd if=/dev/zero of=/dev/mmcblk0p2 bs=2048 count=32
32+0 records in
32+0 records out
65536 bytes (66 kB, 64 KiB) copied, 0.000156408 s, 419 MB/s
ubuntu@ubuntu:~$ sudo dd if=/dev/zero of=/dev/mmcblk0 bs=2048 count=32
32+0 records in
32+0 records out
65536 bytes (66 kB, 64 KiB) copied, 26.9264 s, 2.4 kB/s
请建议是否有办法删除这个讨厌的分区，或者这是否是一个失败的原因并且 SD 卡无法挽救。
ubuntu@ubuntu:~$ sudo fdisk /dev/mmcblk0
Welcome to fdisk (util-linux 2.36.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
The backup GPT table is corrupt, but the primary appears OK, so that will be used.
Command (m for help): p
Disk /dev/mmcblk0: 7.4 GiB, 7948206080 bytes, 15523840 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 321960E8-BABE-4EF1-907A-84F301351CAA
Device Start End Sectors Size Type
/dev/mmcblk0p1 2048 34815 32768 16M unknown
/dev/mmcblk0p2 34816 15523806 15488991 7.4G unknown
Command (m for help): d
Partition number (1,2, default 2): 1
Partition 1 has been deleted.
Command (m for help): d
Selected partition 2
Partition 2 has been deleted.
Command (m for help): p
Disk /dev/mmcblk0: 7.4 GiB, 7948206080 bytes, 15523840 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 321960E8-BABE-4EF1-907A-84F301351CAA
Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
ubuntu@ubuntu:~$ sudo fdisk /dev/mmcblk0
Welcome to fdisk (util-linux 2.36.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
The backup GPT table is corrupt, but the primary appears OK, so that will be used.
Command (m for help): p
Disk /dev/mmcblk0: 7.4 GiB, 7948206080 bytes, 15523840 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 321960E8-BABE-4EF1-907A-84F301351CAA
Device Start End Sectors Size Type
/dev/mmcblk0p1 2048 34815 32768 16M unknown
/dev/mmcblk0p2 34816 15523806 15488991 7.4G unknown
Command (m for help):