[Magisk] Nephiel:
I am trying to install modules on a Doogee S60 (Android 7.0) but I am stumped.

Apparently, Magisk 15.2 is installed OK:

Root apps work.

Passes SafetyNet checks (although I understand it won't pass once Xposed is installed).

Here's the Magisk log:

01-03 22:11:19.592 303 303 I Magisk : Magisk v15.2(1520) daemon started
01-03 22:11:19.600 303 308 I Magisk : ** post-fs mode running
01-03 22:11:46.316 303 2012 I Magisk : ** post-fs-data mode running
01-03 23:11:46.323 303 2012 I Magisk : * Creating /sbin overlay
01-03 23:11:46.325 303 2012 I Magisk : * Mounting mirrors
01-03 23:11:46.326 303 2012 I Magisk : mount: /sbin/.core/mirror/system
01-03 23:11:46.326 303 2012 I Magisk : link: /sbin/.core/mirror/vendor
01-03 23:11:46.328 303 2012 I Magisk : bind_mount: /sbin/.core/mirror/bin
01-03 23:11:46.328 303 2012 I Magisk : * Setting up internal busybox
01-03 23:11:46.359 303 2012 I Magisk : * Mounting /data/adb/magisk.img
01-03 23:11:46.411 303 2012 E Magisk : mount /dev/block/loop0->/sbin/.core/img failed with 13: Permission denied
01-03 23:11:46.412 303 2012 E Magisk : umount /sbin/.core/img failed with 22: Invalid argument
01-03 23:11:46.493 303 2012 E Magisk : mount /dev/block/loop0->/sbin/.core/img failed with 13: Permission denied
01-03 23:11:46.495 303 2012 I Magisk : * Running post-fs-data.d scripts
01-03 23:11:46.495 303 2012 I Magisk : * Running module post-fs-data scripts
01-03 23:11:46.495 303 2012 I Magisk : * Loading modules
01-03 23:11:46.496 303 2019 I Magisk : * Starting MagiskHide
01-03 23:11:46.496 303 2019 I Magisk : hide_utils: Hiding sensitive props
01-03 23:11:46.498 303 2019 E Magisk : fopen: /sbin/.core/img/.core/hidelist failed with 2: No such file or directory
01-03 23:11:46.498 303 2019 I Magisk : hide_list add: [com.google.android.gms.unstable]
01-03 23:11:46.569 303 2019 I Magisk : proc_monitor: init ns=mnt:[4026531840]
01-03 23:11:47.726 303 2159 I Magisk : ** late_start service mode running
01-03 23:11:47.726 303 2159 I Magisk : * Running service.d scripts
01-03 23:11:47.727 303 2159 I Magisk : * Running module service scripts
01-03 23:11:49.364 303 2019 I Magisk : proc_monitor: zygote ns=mnt:[4026533993] zygote64 ns=mnt:[4026533992]
01-03 23:12:30.060 303 2019 I Magisk : proc_monitor: com.google.android.gms.unstable (PID=5454 ns=mnt:[4026534053])
01-03 23:12:49.862 303 2019 I Magisk : proc_monitor: com.google.android.gms.unstable (PID=6738 ns=mnt:[4026534050])

Looks like it's failing to mount /dev/block/loop0 to /sbin/.core/img due to permissions, but when I check, it seems to be mounted:

S60:/ $ su
S60:/ # ls -lha /sbin/.core/img
total 0
drwxr-xr-x 3 root root 60 2018-01-03 23:11 .
drwxr-xr-x 5 root root 100 2018-01-03 23:11 ..
drwxr-xr-x 5 root root 120 2018-01-03 23:11 .core
S60:/ # ls -lha /sbin/.core/img/.core
total 4.0K
drwxr-xr-x 5 root root 120 2018-01-03 23:11 .
drwxr-xr-x 3 root root 60 2018-01-03 23:11 ..
-rw-rw-rw- 1 root root 32 2018-01-03 23:11 hidelist
drwxr-xr-x 2 root root 40 2018-01-03 23:11 post-fs-data.d
drwxr-xr-x 2 root root 40 2018-01-03 23:11 props
drwxr-xr-x 2 root root 40 2018-01-03 23:11 service.d
S60:/ #

Here's the output of "mount", no F2FS partitions AFAIK:

rootfs on / type rootfs (ro,seclabel)
tmpfs on /dev type tmpfs (rw,seclabel,nosuid,relatime,mode=755)
devpts on /dev/pts type devpts (rw,seclabel,relatime,mode=600)
proc on /proc type proc (rw,relatime,gid=3009,hidepid=2)
sysfs on /sys type sysfs (rw,seclabel,relatime)
selinuxfs on /sys/fs/selinux type selinuxfs (rw,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,seclabel,relatime)
none on /acct type cgroup (rw,relatime,cpuacct)
tmpfs on /mnt type tmpfs (rw,seclabel,relatime,mode=755,gid=1000)
none on /config type configfs (rw,relatime)
none on /dev/cpuctl type cgroup (rw,relatime,cpu)
pstore on /sys/fs/pstore type pstore (rw,seclabel,relatime)
tracefs on /sys/kernel/debug/tracing type tracefs (rw,seclabel,relatime)
/dev/block/mmcblk0p25 on /system type ext4 (ro,seclabel,relatime,data=ordered)
/dev/block/mmcblk0p26 on /cache type ext4 (rw,seclabel,nosuid,nodev,noatime,discard,noauto_da_alloc,data=ordered)
/dev/block/mmcblk0p9 on /protect_f type ext4 (rw,seclabel,nosuid,nodev,noatime,nodelalloc,noauto_da_alloc,commit=1,data=ordered)
/dev/block/mmcblk0p10 on /protect_s type ext4 (rw,seclabel,nosuid,nodev,noatime,nodelalloc,noauto_da_alloc,commit=1,data=ordered)
/dev/block/mmcblk0p7 on /nvdata type ext4 (rw,seclabel,nosuid,nodev,noatime,discard,noauto_da_alloc,data=ordered)
/dev/block/mmcblk0p6 on /nvcfg type ext4 (rw,seclabel,nosuid,nodev,noatime,nodelalloc,noauto_da_alloc,commit=1,data=ordered)
adb on /dev/usb-ffs/adb type functionfs (rw,relatime)
tmpfs on /storage type tmpfs (rw,seclabel,relatime,mode=755,gid=1000)
/dev/block/dm-0 on /data type ext4 (rw,seclabel,nosuid,nodev,noatime,discard,noauto_da_alloc,resuid=10010,data=ordered)
tmpfs on /sbin type tmpfs (rw,seclabel,relatime)
/dev/block/mmcblk0p25 on /sbin/.core/mirror/system type ext4 (ro,seclabel,relatime,data=ordered)
/dev/block/dm-0 on /sbin/.core/mirror/bin type ext4 (rw,seclabel,nosuid,nodev,noatime,discard,noauto_da_alloc,resuid=10010,data=ordered)
/data/media on /mnt/runtime/default/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,uid=1023,gid=1023,multiuser)
/data/media on /storage/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,uid=1023,gid=1023,multiuser)
/data/media on /mnt/runtime/read/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,uid=1023,gid=1023,multiuser)
/data/media on /mnt/runtime/write/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,uid=1023,gid=1023,multiuser)
/dev/block/vold/public:179,129 on /mnt/media_rw/9689-3FAB type vfat (rw,dirsync,nosuid,nodev,noexec,relatime,uid=1023,gid=1023,fmask=0007,dmask=0007,allow_utime=0020,codepage=437,iocharset=iso8859-1,shortname=mixed,utf8,errors=remount-ro)
/mnt/media_rw/9689-3FAB on /mnt/runtime/default/9689-3FAB type sdcardfs (rw,nosuid,nodev,noexec,noatime,uid=1023,gid=1023)
/mnt/media_rw/9689-3FAB on /storage/9689-3FAB type sdcardfs (rw,nosuid,nodev,noexec,noatime,uid=1023,gid=1023)
/mnt/media_rw/9689-3FAB on /mnt/runtime/read/9689-3FAB type sdcardfs (rw,nosuid,nodev,noexec,noatime,uid=1023,gid=1023)
/mnt/media_rw/9689-3FAB on /mnt/runtime/write/9689-3FAB type sdcardfs (rw,nosuid,nodev,noexec,noatime,uid=1023,gid=1023)
/dev/block/dm-0 on /data/user_de/0/com.topjohnwu.magisk/databases/su.db type ext4 (rw,seclabel,nosuid,nodev,noatime,discard,noauto_da_alloc,resuid=10010,data=ordered)

Here's the install log for one of the Xposed Framework modules (the one by ahrion):

- Copying zip to temp directory
- Installing Xposed_Framework-v89r4.zip

Unzipping files...
Archive: /data/user/0/com.topjohnwu.magisk/cache/install.zip
inflating: .gitattributes
inflating: META-INF/com/google/android/update-binary
inflating: META-INF/com/google/android/updater-script
inflating: README.md
inflating: common/aml-patches-remove.sh
inflating: common/aml-patches-wipe.sh
inflating: common/aml-patches.sh
inflating: common/post-fs-data.sh
inflating: common/service.sh
inflating: common/system.prop
inflating: common/unity-audmodlib/audmodlib-post-fs-data.sh
inflating: common/unity-audmodlib/audmodlibmodule.prop
inflating: common/unity-audmodlib/modid.sh
inflating: common/unity-customrules1.sh
inflating: common/unity-customrules2.sh
inflating: common/unity-customrules3.sh
inflating: common/unity-files-wipe.sh
inflating: common/unity-uservariables.sh
inflating: config.sh
inflating: custom/21/arm/bin/app_process32
inflating: custom/21/arm/bin/app_process32_magisk
inflating: custom/21/arm/bin/dex2oat
inflating: custom/21/arm/bin/oatdump
inflating: custom/21/arm/bin/patchoat
inflating: custom/21/arm/lib/libart-compiler.so
inflating: custom/21/arm/lib/libart-disassembler.so
inflating: custom/21/arm/lib/libart.so
inflating: custom/21/arm/lib/libsigchain.so
inflating: custom/21/arm/lib/libxposed_art.so
inflating: custom/21/arm/xposed.prop
inflating: custom/21/arm64/bin/app_process32
inflating: custom/21/arm64/bin/app_process32_magisk
inflating: custom/21/arm64/bin/app_process64
inflating: custom/21/arm64/bin/app_process64_magisk
inflating: custom/21/arm64/bin/dex2oat
inflating: custom/21/arm64/bin/oatdump
inflating: custom/21/arm64/bin/patchoat
inflating: custom/21/arm64/lib/libart-compiler.so
inflating: custom/21/arm64/lib/libart.so
inflating: custom/21/arm64/lib/libsigchain.so
inflating: custom/21/arm64/lib/libxposed_art.so
inflating: custom/21/arm64/lib64/libart-disassembler.so
inflating: custom/21/arm64/lib64/libart.so
inflating: custom/21/arm64/lib64/libsigchain.so
inflating: custom/21/arm64/lib64/libxposed_art.so
inflating: custom/21/arm64/xposed.prop
inflating: custom/21/x86/bin/app_process32
inflating: custom/21/x86/bin/app_process32_magisk
inflating: custom/21/x86/bin/dex2oat
inflating: custom/21/x86/bin/oatdump
inflating: custom/21/x86/bin/patchoat
inflating: custom/21/x86/lib/libart-compiler.so
inflating: custom/21/x86/lib/libart-disassembler.so
inflating: custom/21/x86/lib/libart.so
inflating: custom/21/x86/lib/libsigchain.so
inflating: custom/21/x86/lib/libxposed_art.so
inflating: custom/21/x86/xposed.prop
inflating: custom/22/arm/bin/app_process32
inflating: custom/22/arm/bin/app_process32_magisk
inflating: custom/22/arm/bin/dex2oat
inflating: custom/22/arm/bin/oatdump
inflating: custom/22/arm/bin/patchoat
inflating: custom/22/arm/lib/libart-compiler.so
inflating: custom/22/arm/lib/libart-disassembler.so
inflating: custom/22/arm/lib/libart.so
inflating: custom/22/arm/lib/libsigchain.so
inflating: custom/22/arm/lib/libxposed_art.so
inflating: custom/22/arm/xposed.prop
inflating: custom/22/arm64/bin/app_process32
inflating: custom/22/arm64/bin/app_process32_magisk
inflating: custom/22/arm64/bin/app_process64
inflating: custom/22/arm64/bin/app_process64_magisk
inflating: custom/22/arm64/bin/dex2oat
inflating: custom/22/arm64/bin/oatdump
inflating: custom/22/arm64/bin/patchoat
inflating: custom/22/arm64/lib/libart-compiler.so
inflating: custom/22/arm64/lib/libart.so
inflating: custom/22/arm64/lib/libsigchain.so
inflating: custom/22/arm64/lib/libxposed_art.so
inflating: custom/22/arm64/lib64/libart-disassembler.so
inflating: custom/22/arm64/lib64/libart.so
inflating: custom/22/arm64/lib64/libsigchain.so
inflating: custom/22/arm64/lib64/libxposed_art.so
inflating: custom/22/arm64/xposed.prop
inflating: custom/22/x86/bin/app_process32
inflating: custom/22/x86/bin/app_process32_magisk
inflating: custom/22/x86/bin/dex2oat
inflating: custom/22/x86/bin/oatdump
inflating: custom/22/x86/bin/patchoat
inflating: custom/22/x86/lib/libart-compiler.so
inflating: custom/22/x86/lib/libart-disassembler.so
inflating: custom/22/x86/lib/libart.so
inflating: custom/22/x86/lib/libsigchain.so
inflating: custom/22/x86/lib/libxposed_art.so
inflating: custom/22/x86/xposed.prop
inflating: custom/23/arm/bin/app_process32
inflating: custom/23/arm/bin/app_process32_magisk
inflating: custom/23/arm/bin/dex2oat
inflating: custom/23/arm/bin/oatdump
inflating: custom/23/arm/bin/patchoat
inflating: custom/23/arm/lib/libart-compiler.so
inflating: custom/23/arm/lib/libart-disassembler.so
inflating: custom/23/arm/lib/libart.so
inflating: custom/23/arm/lib/libsigchain.so
inflating: custom/23/arm/lib/libxposed_art.so
inflating: custom/23/arm/xposed.prop
inflating: custom/23/arm64/bin/app_process32
inflating: custom/23/arm64/bin/app_process32_magisk
inflating: custom/23/arm64/bin/app_process64
inflating: custom/23/arm64/bin/app_process64_magisk
inflating: custom/23/arm64/bin/dex2oat
inflating: custom/23/arm64/bin/oatdump
inflating: custom/23/arm64/bin/patchoat
inflating: custom/23/arm64/lib/libart-compiler.so
inflating: custom/23/arm64/lib/libart.so
inflating: custom/23/arm64/lib/libsigchain.so
inflating: custom/23/arm64/lib/libxposed_art.so
inflating: custom/23/arm64/lib64/libart-disassembler.so
inflating: custom/23/arm64/lib64/libart.so
inflating: custom/23/arm64/lib64/libsigchain.so
inflating: custom/23/arm64/lib64/libxposed_art.so
inflating: custom/23/arm64/xposed.prop
inflating: custom/23/x86/bin/app_process32
inflating: custom/23/x86/bin/app_process32_magisk
inflating: custom/23/x86/bin/dex2oat
inflating: custom/23/x86/bin/oatdump
inflating: custom/23/x86/bin/patchoat
inflating: custom/23/x86/lib/libart-compiler.so
inflating: custom/23/x86/lib/libart-disassembler.so
inflating: custom/23/x86/lib/libart.so
inflating: custom/23/x86/lib/libsigchain.so
inflating: custom/23/x86/lib/libxposed_art.so
inflating: custom/23/x86/xposed.prop
inflating: custom/24/arm/bin/app_process32
inflating: custom/24/arm/bin/app_process32_magisk
inflating: custom/24/arm/bin/dex2oat
inflating: custom/24/arm/bin/oatdump
inflating: custom/24/arm/bin/patchoat
inflating: custom/24/arm/lib/libart-compiler.so
inflating: custom/24/arm/lib/libart-disassembler.so
inflating: custom/24/arm/lib/libart.so
inflating: custom/24/arm/lib/libsigchain.so
inflating: custom/24/arm/lib/libxposed_art.so
inflating: custom/24/arm/xposed.prop
inflating: custom/24/arm64/bin/app_process32
inflating: custom/24/arm64/bin/app_process32_magisk
inflating: custom/24/arm64/bin/app_process64
inflating: custom/24/arm64/bin/app_process64_magisk
inflating: custom/24/arm64/bin/dex2oat
inflating: custom/24/arm64/bin/oatdump
inflating: custom/24/arm64/bin/patchoat
inflating: custom/24/arm64/lib/libart-compiler.so
inflating: custom/24/arm64/lib/libart.so
inflating: custom/24/arm64/lib/libsigchain.so
inflating: custom/24/arm64/lib/libxposed_art.so
inflating: custom/24/arm64/lib64/libart-compiler.so
inflating: custom/24/arm64/lib64/libart-disassembler.so
inflating: custom/24/arm64/lib64/libart.so
inflating: custom/24/arm64/lib64/libsigchain.so
inflating: custom/24/arm64/lib64/libxposed_art.so
inflating: custom/24/arm64/xposed.prop
inflating: custom/24/x86/bin/app_process32
inflating: custom/24/x86/bin/app_process32_magisk
inflating: custom/24/x86/bin/dex2oat
inflating: custom/24/x86/bin/oatdump
inflating: custom/24/x86/bin/patchoat
inflating: custom/24/x86/lib/libart-compiler.so
inflating: custom/24/x86/lib/libart-disassembler.so
inflating: custom/24/x86/lib/libart.so
inflating: custom/24/x86/lib/libsigchain.so
inflating: custom/24/x86/lib/libxposed_art.so
inflating: custom/24/x86/xposed.prop
inflating: custom/25/arm/bin/app_process32
inflating: custom/25/arm/bin/app_process32_magisk
inflating: custom/25/arm/bin/dex2oat
inflating: custom/25/arm/bin/oatdump
inflating: custom/25/arm/bin/patchoat
inflating: custom/25/arm/lib/libart-compiler.so
inflating: custom/25/arm/lib/libart-disassembler.so
inflating: custom/25/arm/lib/libart.so
inflating: custom/25/arm/lib/libsigchain.so
inflating: custom/25/arm/lib/libxposed_art.so
inflating: custom/25/arm/xposed.prop
inflating: custom/25/arm64/bin/app_process32
inflating: custom/25/arm64/bin/app_process32_magisk
inflating: custom/25/arm64/bin/app_process64
inflating: custom/25/arm64/bin/app_process64_magisk
inflating: custom/25/arm64/bin/dex2oat
inflating: custom/25/arm64/bin/oatdump
inflating: custom/25/arm64/bin/patchoat
inflating: custom/25/arm64/lib/libart-compiler.so
inflating: custom/25/arm64/lib/libart.so
inflating: custom/25/arm64/lib/libsigchain.so
inflating: custom/25/arm64/lib/libxposed_art.so
inflating: custom/25/arm64/lib64/libart-compiler.so
inflating: custom/25/arm64/lib64/libart-disassembler.so
inflating: custom/25/arm64/lib64/libart.so
inflating: custom/25/arm64/lib64/libsigchain.so
inflating: custom/25/arm64/lib64/libxposed_art.so
inflating: custom/25/arm64/xposed.prop
inflating: custom/25/x86/bin/app_process32
inflating: custom/25/x86/bin/app_process32_magisk
inflating: custom/25/x86/bin/dex2oat
inflating: custom/25/x86/bin/oatdump
inflating: custom/25/x86/bin/patchoat
inflating: custom/25/x86/lib/libart-compiler.so
inflating: custom/25/x86/lib/libart-disassembler.so
inflating: custom/25/x86/lib/libart.so
inflating: custom/25/x86/lib/libsigchain.so
inflating: custom/25/x86/lib/libxposed_art.so
inflating: custom/25/x86/xposed.prop
inflating: data/placeholder
inflating: module.prop
inflating: system/addon.d/audmodlib.sh
inflating: system/addon.d/modid.sh
inflating: system/app/XposedInstaller/XposedInstaller.apk
inflating: system/framework/XposedBridge.jar
inflating: META-INF/MANIFEST.MF
inflating: META-INF/CERT.SF
inflating: META-INF/CERT.RSA

*******************************************
* Xposed Framework *
*******************************************
* v89r4 *
* by rovo89, ahrion, zackptg5 *
*******************************************

- Mounting /data, /cache
- Mounting /system, /vendor
- Magisk install detected
- Creating /data/adb/magisk_merge.img with size 224M
Creating filesystem with parameters:
Size: 234881024
Block size: 4096
Blocks per group: 32768
Inodes per group: 7168
Inode size: 256
Journal blocks: 1024
Label:
Blocks: 57344
Block groups: 2
Reserved block group size: 15
Created filesystem with 11/14336 inodes and 1961/57344 blocks
- Mounting /data/adb/magisk_merge.img to /dev/tmp/magisk_img
! /data/adb/magisk_merge.img mount failed...
Failed!
! Installation failed

Here's the install log for Xposed Framework SDK 24 (the one by topjohnwu):

- Copying zip to temp directory
- Installing Xposed_Framework_SDK_24-89.0_Systemless_by_topjohnwu.zip
- Mounting /system, /vendor, /data, /cache
! Magisk is not activated!
Failed!
! Installation failed

Any pointers?