Failed to mount sdcardfs on DragonBoard 845c

I build and flash by referring to this site ( https://wiki.linaro.org/AOSP/db845c )
But failed to mount sdcardfs
when I use this image, device is normal operation
http://snapshots.linaro.org/96boards/dragonboard845c/linaro/aosp-master/408/
Is there anything else to check?

--------- beginning of system
08-31 05:32:17.572 1199 1199 W sdcard : Device explicitly enabled sdcardfs
08-31 05:32:17.572 1199 1199 W sdcard : Failed to mount sdcardfs with options fsuid=1023,fsgid=1023,multiuser,derive_gid,default_normal,unshared_obb,mask=6,userid=0,gid=1015: No such device
08-31 05:32:17.572 1199 1199 W sdcard : Failed to mount sdcardfs with options fsuid=1023,fsgid=1023,multiuser,derive_gid,default_normal,mask=6,userid=0,gid=1015: No such device
08-31 05:32:17.573 1199 1199 W sdcard : Failed to mount sdcardfs with options fsuid=1023,fsgid=1023,multiuser,derive_gid,mask=6,userid=0,gid=1015: No such device
08-31 05:32:17.573 1199 1199 W sdcard : Failed to mount sdcardfs with options fsuid=1023,fsgid=1023,multiuser,mask=6,userid=0,gid=1015: No such device
08-31 05:32:17.573 1199 1199 W sdcard : Failed to mount sdcardfs with options fsuid=1023,fsgid=1023,mask=6,userid=0,gid=1015: No such device
08-31 05:32:17.573 1199 1199 F sdcard : sdcard.cpp:190] failed to sdcardfs_setup
--------- beginning of crash
08-31 05:32:17.573 1199 1199 F libc : Fatal signal 6 (SIGABRT), code -1 (SI_QUEUE) in tid 1199 (sdcard), pid 1199 (sdcard)

Which kernel version failed to mount sdcardfs? sdcardfs is discontinued since android-mainline-5.7. So if you are booting v5.7 or newer there is no sdcardfs support.

http://snapshots.linaro.org/96boards/dragonboard845c/linaro/aosp-master/ prebuilt images boot with v5.4.y, hence you don’t see this sdcardfs mount problem there.

Thanks,
Amit Pundir

Which kernel version failed to mount sdcardfs?
-> 5.4 kernel

using this command for source download
Already sdcardfs has been deleted in common-android11-5.4
Therefore, this problem still occurs in db845c

repo init -u https://android.googlesource.com/kernel/manifest -b common-android11-5.4

commit c6d419d9ff6ee687a83dc4798e0e0be46fa3050a
Author: Greg Kroah-Hartman gregkh@google.com
Date: Fri May 29 09:37:57 2020 +0200

ANDROID: sdcardfs: remove sdcardfs from system

It's no longer needed on Android devices, so remove sdcardfs core code,
and a bunch of exports that were only added so that it could be built as
a module.

Bug: 157700134
Cc: Daniel Rosenberg <drosen@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I2b5c1103a79c07dcbd7273b42ac4b7ddf4615d38

Argh… I forgot about android11-5.4. Any reason you want to stick to android11-5.4? android12-5.4 still has sdcardfs support. If you want to stick to android11-5.4, I suggest you revert this commit (c6d419d9ff6ee6 ANDROID: sdcardfs: remove sdcardfs from system), since you are building your kernel from source anyway.

FWIW Android11 and beyond is not using sdcardfs. They have switched to a new feature called “scoped storage”, https://developer.android.com/preview/privacy/storage, implemented using Fuse and ext4/f2fs case folding. Scoped storage code has not landed in AOSP yet, so you have to live with sdcardfs till then.