我有一张 16 GB 的 SanDisk MicroSD 卡，可以使用 MicroSD 转 SD 卡适配器（该适配器插入 SD 转 USB 适配器）插入我的笔记本电脑。
它曾经工作正常，但是现在当我插入卡时，我收到一条错误消息，说无法安装其中一个分区：
无法访问“用户数据” - 在 /media/krisztian/userdata 上安装 /dev/sdb4 时出错：无法以只读方式安装 /dev/sdb4
这是输出dmesg：
[ 635.485229] usb 1-1: new high-speed USB device number 5 using xhci_hcd
[ 635.647023] usb 1-1: New USB device found, idVendor=05e3, idProduct=0723, bcdDevice=94.51
[ 635.647032] usb 1-1: New USB device strings: Mfr=3, Product=4, SerialNumber=2
[ 635.647038] usb 1-1: Product: USB Storage
[ 635.647042] usb 1-1: Manufacturer: Generic
[ 635.647046] usb 1-1: SerialNumber: 000000009451
[ 635.700240] usb-storage 1-1:1.0: USB Mass Storage device detected
[ 635.700345] usb-storage 1-1:1.0: Quirks match for vid 05e3 pid 0723: 8000
[ 635.700392] scsi host3: usb-storage 1-1:1.0
[ 635.700549] usbcore: registered new interface driver usb-storage
[ 635.705394] usbcore: registered new interface driver uas
[ 636.710912] scsi 3:0:0:0: Direct-Access Generic STORAGE DEVICE 9451 PQ: 0 ANSI: 0
[ 636.711702] scsi 3:0:0:0: Attached scsi generic sg2 type 0
[ 636.958089] sd 3:0:0:0: [sdb] 31116288 512-byte logical blocks: (15.9 GB/14.8 GiB)
[ 636.959123] sd 3:0:0:0: [sdb] Write Protect is on
[ 636.959126] sd 3:0:0:0: [sdb] Mode Sense: 03 00 80 00
[ 636.960057] sd 3:0:0:0: [sdb] No Caching mode page found
[ 636.960062] sd 3:0:0:0: [sdb] Assuming drive cache: write through
[ 636.985619] sdb: sdb1 sdb2 sdb3 sdb4
[ 636.989887] sd 3:0:0:0: [sdb] Attached SCSI removable disk
[ 637.803657] EXT4-fs (sdb2): mounted filesystem without journal. Opts: (null)
[ 637.841704] EXT4-fs (sdb3): mounted filesystem without journal. Opts: (null)
[ 637.867540] EXT4-fs (sdb4): INFO: recovery required on readonly filesystem
[ 637.867542] EXT4-fs (sdb4): write access unavailable, cannot proceed (try mounting with noload)
[ 648.934742] EXT4-fs (sdb4): INFO: recovery required on readonly filesystem
[ 648.934745] EXT4-fs (sdb4): write access unavailable, cannot proceed (try mounting with noload)
[ 655.244375] EXT4-fs (sdb4): INFO: recovery required on readonly filesystem
[ 655.244379] EXT4-fs (sdb4): write access unavailable, cannot proceed (try mounting with noload)
[ 676.986825] EXT4-fs (sdb4): INFO: recovery required on readonly filesystem
[ 676.986829] EXT4-fs (sdb4): write access unavailable, cannot proceed (try mounting with noload)
它显示“写保护已打开”，但我不知道为什么。我检查了适配器的锁定开关。它肯定处于“解锁”位置。
这是输出mount：
/dev/sdb1 on /media/krisztian/boot type vfat (ro,nosuid,nodev,relatime,uid=1000,gid=1000,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,showexec,utf8,flush,errors=remount-ro,uhelper=udisks2)
/dev/sdb2 on /media/krisztian/_ type ext4 (ro,nosuid,nodev,relatime,uhelper=udisks2)
/dev/sdb3 on /media/krisztian/vendor type ext4 (ro,nosuid,nodev,relatime,uhelper=udisks2)
如您所见，/dev/sdb4它没有显示出来，并且所有其他分区都以只读方式安装。
在 MicroSD 卡上，我已将 LineageOS 刷入其中。我尝试再次将图像刷入卡中，但收到以下消息：
krisztian@laptop:~/Downloads$ unzip -p lineage-17.1-20201108-UNOFFICIAL-KonstaKANG-rpi3.zip | sudo dd of=/dev/sdb bs=4M conv=fsync
[sudo] password for krisztian:
dd: failed to open '/dev/sdb': Read-only file system
有任何想法吗？
更新：
我也试过其他 SD 卡，它们都安装时显示“写保护已打开”。所以我认为问题不在于卡。可能是 USB 读卡器坏了。
答案1
我终于买了一个新的读卡器，卡可以用它。所以问题只是读卡器坏了。