无法访问SD卡
我将SD卡的文件系统格式更改为NTFS，以便我的系统上的应用程序写入它。 我再也无法访问它，所以我将其更改回FAT，但我仍然无法以root用户身份或常规用户访问它。 作为root，它没有列出。 至于用户访问，我收到一个错误弹出窗口，显示“无法访问32 GB卷，无权执行操作”。
df命令给出了以下输出：
Filesystem 1K-blocks Used Available Use% Mounted on /dev/mmcblk0p1 10732080 8523064 1640800 84% / devtmpfs 995380 0 995380 0% /dev shmfs 997360 52396 944964 6% /dev/shm tmp 997360 19924 977436 2% /tmp tmpfs 199476 56 199420 1% /run tmpfs 5120 0 5120 0% /run/lock run 997360 448 996912 1% /var/host/dbus /dev/mapper/encstateful 3164880 139276 3009220 5% /var/host/timezone /dev/root 1763840 1583608 180232 90% /lib/modules/3.18.0-13527-gc2f2230 media 997360 4 997356 1% /var/host/media /home/.shadow/dbb3045.../vault 10732080 8523064 1640800 84% /home/friskybits/Downloads none 997360 0 997360 0% /sys/fs/cgroup none 997360 4
sudo lsblk -f命令给出了以下输出：
NAME FSTYPE LABEL MOUNTPOINT loop0 └─encstateful (dm-1) ext4 loop1 squashfs loop2 squashfs loop3 squashfs loop4 squashfs loop5 squashfs loop6 squashfs zram0 [SWAP] mmcblk0rpmb mmcblk0boot0 mmcblk0boot1 mmcblk0 ├─mmcblk0p1 ext4 ├─mmcblk0p2 ├─mmcblk0p3 ext4 ROOT-A │ └─vroot (dm-0) ├─mmcblk0p4 ├─mmcblk0p5 ext4 ROOT-A ├─mmcblk0p6 ├─mmcblk0p7 ├─mmcblk0p8 ext4 OEM ├─mmcblk0p9 ├─mmcblk0p10 ├─mmcblk0p11 └─mmcblk0p12 vfat EFI-SYSTEM mmcblk1 └─mmcblk1p1 vfat
sudo lsblk -m命令给出了以下输出：
NAME SIZE OWNER GROUP MODE loop0 3.1G root disk brw-rw---- └─encstateful (dm-1) 3.1G root root brw------- loop1 397.5M root disk brw-rw---- loop2 48.8M root disk brw-rw---- loop3 4K root disk brw-rw---- loop4 4K root disk brw-rw---- loop5 4K root disk brw-rw---- loop6 4K root disk brw-rw---- zram0 2.8G root disk brw-rw---- mmcblk0rpmb 4M root disk brw-rw---- mmcblk0boot0 4M root disk brw-rw---- mmcblk0boot1 4M root disk brw-rw---- mmcblk0 14.7G root disk brw-rw---- ├─mmcblk0p1 10.5G root disk brw-rw---- ├─mmcblk0p2 16M root disk brw-rw---- ├─mmcblk0p3 2G root disk brw-rw---- │ └─vroot (dm-0) 1.7G root root --------- ├─mmcblk0p4 16M root disk brw-rw---- ├─mmcblk0p5 2G root disk brw-rw---- ├─mmcblk0p6 512B root disk brw-rw---- ├─mmcblk0p7 512B root disk brw-rw---- ├─mmcblk0p8 16M root disk brw-rw---- ├─mmcblk0p9 512B root disk brw-rw---- ├─mmcblk0p10 512B root disk brw-rw---- ├─mmcblk0p11 8M root disk brw-rw---- └─mmcblk0p12 16M root disk brw-rw---- mmcblk1 29.7G root disk brw-rw---- └─mmcblk1p1 29.7G root disk brw-rw----
而sudo parted -ls命令给了我以下输出：
Model: Linux device-mapper (crypt) (dm) Disk /dev/mapper/encstateful: 3297MB Sector size (logical/physical): 512B/512B Partition Table: loop Number Start End Size File system Flags 1 0.00B 3297MB 3297MB ext4 Error: /dev/mmcblk0rpmb: unrecognised disk label Warning: Error fsyncing/closing /dev/mmcblk0rpmb: Input/output error Error: /dev/mmcblk0boot0: unrecognised disk label Error: /dev/mmcblk0boot1: unrecognised disk label Model: MMC 400073 (sd/mmc) Disk /dev/mmcblk0: 15.8GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 11 32.8kB 8421kB 8389kB RWFW 6 8421kB 8422kB 512B KERN-C 7 8422kB 8422kB 512B ROOT-C 9 8422kB 8423kB 512B reserved 10 8423kB 8423kB 512B reserved 2 10.5MB 27.3MB 16.8MB KERN-A 4 27.3MB 44.0MB 16.8MB KERN-B 8 44.0MB 60.8MB 16.8MB ext4 OEM msftdata 12 128MB 145MB 16.8MB fat16 EFI-SYSTEM boot 5 145MB 2292MB 2147MB ext2 ROOT-B 3 2292MB 4440MB 2147MB ext2 ROOT-A 1 4440MB 15.7GB 11.3GB ext4 STATE msftdata Warning: /dev/mmcblk1 contains GPT signatures, indicating that it has a GPT table. However, it does not have a valid fake msdos partition table, as it should. Perhaps it was corrupted -- possibly by a program that doesn't understand GPT partition tables. Or perhaps you deleted the GPT table, and are now using an msdos partition table. Is this a GPT partition table? Error: The backup GPT table is corrupt, but the primary appears OK, so that will be used. Model: SD SS32G (sd/mmc) Disk /dev/mmcblk1: 31.9GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 11 32.8kB 8421kB 8389kB RWFW 6 8421kB 8422kB 512B KERN-C 7 8422kB 8422kB 512B ROOT-C 9 8422kB 8423kB 512B reserved 10 8423kB 8423kB 512B reserved 2 10.5MB 27.3MB 16.8MB KERN-A 4 27.3MB 44.0MB 16.8MB KERN-B 8 44.0MB 60.8MB 16.8MB OEM msftdata 12 128MB 145MB 16.8MB EFI-SYSTEM boot 5 145MB 147MB 2097kB ROOT-B 3 147MB 2244MB 2097MB ROOT-A 1 2244MB 2263MB 18.9MB STATE msftdata
我该如何访问SD卡？
听起来你已经打开了一些安装了SD卡的应用程序，阻止root /用户安装它。 检查gparted是否打开它。
在具有每个人写入权限的SD卡中安装FAT32分区
（假设：SD卡被视为/dev/mmcblk1 ，将mmcblk1p1替换为分区的实际字母，例如sdb1如果USB pendrive或通过USB连接的SD卡， /dev/mmcblk1p1 —> /dev/sdb1 ）
sudo mkdir -p /mnt/sd1 # only if you want a new mountpoint sudo umount /dev/mmcblk1p1 # only if already mounted (but with bad permissions) sudo mount -o rw,users,umask=000 /dev/mmcblk1p1 /mnt/sd1 # mount
或（如果通过USB连接）
sudo mkdir -p /mnt/sd1 # only if you want a new mountpoint sudo umount /dev/sdb1 # only if already mounted (but with bad permissions) sudo mount -o rw,users,umask=000 /dev/sdb1 /mnt/sd1 # mount
检查权限
ls -ld /mnt/sd1
测试
sudo bash -c "echo 'Hello World' > /mnt/sd1/hello.txt" # test writing with sudo cat /mnt/sd1/hello.txt # test reading (as user) ls -l /mnt/sd1 # check permissions of the content rm /mnt/sd1/hello.txt # test removing (as user) echo 'I am a user' > /mnt/sd1/user.txt # test writing (as user)
编辑：使用以下命令行说明不同的umask替代方案，在本例中假设为device /dev/sdb1
$ sudo umount /mnt/sd1; sudo mount -o rw,users,umask=077 /dev/sdb1 /mnt/sd1;ls -ld /mnt/sd1 drwx------ 2 root root 4096 jan 1 1970 /mnt/sd1 # only root has permissions $ sudo umount /mnt/sd1; sudo mount -o rw,users,umask=033 /dev/sdb1 /mnt/sd1;ls -ld /mnt/sd1 drwxr--r-- 2 root root 4096 jan 1 1970 /mnt/sd1 # users have read permissions $ sudo umount /mnt/sd1; sudo mount -o rw,users,umask=022 /dev/sdb1 /mnt/sd1;ls -ld /mnt/sd1 drwxr-xr-x 2 root root 4096 jan 1 1970 /mnt/sd1 # users have read and execute permissions $ sudo umount /mnt/sd1; sudo mount -o rw,users,umask=011 /dev/sdb1 /mnt/sd1;ls -ld /mnt/sd1 drwxrw-rw- 2 root root 4096 jan 1 1970 /mnt/sd1 # users have read and write permissions $ sudo umount /mnt/sd1; sudo mount -o rw,users,umask=000 /dev/sdb1 /mnt/sd1;ls -ld /mnt/sd1 drwxrwxrwx 2 root root 4096 jan 1 1970 /mnt/sd1 # users have full permissions
如果这不起作用
如果这不起作用，您可以在以下链接中找到解决方案或至少解释，
无法格式化我的USB驱动器。 我已经尝试过使用mkdosfs和gparted：分析问题