# Mounting of Android storage

## david.cimburek

Hi there,

I have troubles with mount of mass storage of my Android phone. When I connect the phone with my PC via the usb cable, system recognizes new sdb device:

```
$ dmesg

[945984.008729] hub 2-1:1.0: state 7 ports 4 chg 0000 evt 0008

[945984.009407] hub 2-1:1.0: port 3, status 0101, change 0001, 12 Mb/s

[945984.114438] hub 2-1:1.0: debounce: port 3: total 100ms stable 100ms status 0x101

[945984.125430] hub 2-1:1.0: port 3 not reset yet, waiting 10ms

[945984.187433] usb 2-1.3: new high-speed USB device number 28 using ehci_hcd

[945984.262806] usb 2-1.3: skipped 1 descriptor after configuration

[945984.262905] usb 2-1.3: default language 0x0409

[945984.263283] usb 2-1.3: udev 28, busnum 2, minor = 155

[945984.263289] usb 2-1.3: New USB device found, idVendor=0fce, idProduct=e168

[945984.263294] usb 2-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3

[945984.263299] usb 2-1.3: Product: SEMC HSUSB Device

[945984.263303] usb 2-1.3: Manufacturer: SEMC

[945984.263307] usb 2-1.3: SerialNumber: 43423541314A51563336

[945984.263404] usb 2-1.3: usb_probe_device

[945984.263410] usb 2-1.3: configuration #1 chosen from 1 choice

[945984.263664] usb 2-1.3: adding 2-1.3:1.0 (config #1, interface 0)

[945984.263729] uas 2-1.3:1.0: usb_probe_interface

[945984.263733] uas 2-1.3:1.0: usb_probe_interface - got id

[945984.263754] usb-storage 2-1.3:1.0: usb_probe_interface

[945984.263763] usb-storage 2-1.3:1.0: usb_probe_interface - got id

[945984.263933] scsi23 : usb-storage 2-1.3:1.0

[945984.264092] drivers/usb/core/inode.c: creating file '028'

[945985.266821] scsi 23:0:0:0: Direct-Access     SEMC     Mass Storage     0100 PQ: 0 ANSI: 4

[945985.267050] sd 23:0:0:0: Attached scsi generic sg2 type 0

[945985.270544] sd 23:0:0:0: [sdb] Attached SCSI removable disk
```

But from some strange reason it doesn't recognize that this device has a sdb1 partition and in /proc/partitions is this device missing completely:

```
$ cat /proc/partitions 

major minor  #blocks  name

   8        0  244198584 sda

   8        1   83886080 sda1

   8        2  150994944 sda2

   8        3    9316536 sda3

  11        0     665056 sr0
```

But when I access sdb device somehow as root user, the missing partition suddenly appears!

```
$ sudo /sbin/fdisk -l /dev/sdb

$ dmesg

[946085.910478] sd 23:0:0:0: [sdb] 31116288 512-byte logical blocks: (15.9 GB/14.8 GiB)

[946085.912175] sd 23:0:0:0: [sdb] No Caching mode page present

[946085.912179] sd 23:0:0:0: [sdb] Assuming drive cache: write through

[946085.914185] sd 23:0:0:0: [sdb] No Caching mode page present

[946085.914189] sd 23:0:0:0: [sdb] Assuming drive cache: write through

[946085.916692]  sdb: sdb1

$ cat /proc/partitions 

major minor  #blocks  name

   8        0  244198584 sda

   8        1   83886080 sda1

   8        2  150994944 sda2

   8        3    9316536 sda3

  11        0     665056 sr0

   8       16   15558144 sdb

   8       17   15554048 sdb1
```

What's wrong with my system that it doesn't recognize the device correctly on it's own automatically?

I'm running kernel 3.4.5-gentoo.

Thanks.

----------

## lxg

What version of Android is this? Does the device have an SD slot or only internal storage?

Recent versions of Android don't support USB mounting anymore, you need to use MTP.

Can you mount other USB storage devices?

----------

## david.cimburek

Thanks for reply, I have two phones which behave the same way, one is running Android 2.1 and another 2.3. Both devices have SD cards. The strange thing is that when i touch the /dev/sdb device (as root), the /dev/sdb1 device appears and can be normally mounted...

----------

## lxg

Strange indeed. Can you reproduce it? And, does this still occur after a reboot?

If you can reproduce it, can you say what happens in /var/log/messages *after* you touched /dev/sdb? (Run tail -f /var/log/messages in one console and touch /dev/sdb in another one)

If I'd had to guess, this sounds a bit like a udev hiccup.

----------

## david.cimburek

Yes, this behaviour is 100% reproducible, even after reboot. I'm using metalog so I don't have /var/log/messages, but I can post here content of my /var/log/everything/current. However during the whole procedure there is no udev record in this log file. When I increased the udev verbosity to info level, I've found this interesting part (among lots of other lines):

```
Dec 21 16:16:06 [udevd] IMPORT '/sbin/blkid -o udev -p /dev/sdb' /lib/udev/rules.d/60-persistent-storage.rules:70_

Dec 21 16:16:06 [udevd] starting '/sbin/blkid -o udev -p /dev/sdb'_

Dec 21 16:16:06 [udevd] '/sbin/blkid -o udev -p /dev/sdb'(err) 'error: /dev/sdb: No medium found'_

Dec 21 16:16:06 [udevd] '/sbin/blkid -o udev -p /dev/sdb' [22197] exit with return code 2_ 
```

After accessing /dev/sdb (via fdisk -l) blkid didn't have problems anymore:

```
Dec 21 16:17:01 [udevd] IMPORT '/sbin/blkid -o udev -p /dev/sdb' /lib/udev/rules.d/60-persistent-storage.rules:70_

Dec 21 16:17:01 [udevd] starting '/sbin/blkid -o udev -p /dev/sdb'_

Dec 21 16:17:01 [kernel] [1028240.307181] sd 26:0:0:0: [sdb] No Caching mode page present

Dec 21 16:17:01 [kernel] [1028240.307188] sd 26:0:0:0: [sdb] Assuming drive cache: write through

Dec 21 16:17:01 [udevd] seq 3530 queued, 'change' 'block'_

Dec 21 16:17:01 [udevd] seq 3531 queued, 'add' 'block'_

Dec 21 16:17:01 [kernel] [1028240.310290]  sdb: sdb1
```

This behavior is reproducible in command line:

```
# /sbin/blkid -o udev -p /dev/sdb

error: /dev/sdb: No medium found

# fdisk -l /dev/sdb

# /sbin/blkid -o udev -p /dev/sdb

ID_PART_TABLE_TYPE=dos
```

Why can't blkid locate /dev/sdb during the first attempt?

----------

## lxg

Is this behaviour reproducible with other USB storage devices like USB keys or external harddisks?

----------

## david.cimburek

Other storages are OK, this is only problem of Android...

----------

## VoidMage

If we're talking about logs, perhaps following will show the problem:

- before the device is plugged, run 'udevadm monitor' in terminal

- plug the device in, make sure you can't mount it yet

- do whatever you do to make the device appear, make sure you can mount it now

If the output of 'udevadm monitor' is short enough, paste, otherwise pastebin.

----------

## david.cimburek

Here are the 'udevadm monitor' logs after connecting the phone to PC, now it is /dev/sdc device:

```
KERNEL[1356289952.224460] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5 (usb)

KERNEL[1356289952.224773] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0 (usb)

KERNEL[1356289952.225022] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13 (scsi)

KERNEL[1356289952.225085] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/scsi_host/host13 (scsi_host)

UDEV  [1356289952.228500] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5 (usb)

UDEV  [1356289952.228977] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0 (usb)

UDEV  [1356289952.229331] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13 (scsi)

UDEV  [1356289952.229904] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/scsi_host/host13 (scsi_host)

KERNEL[1356289953.227923] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0 (scsi)

KERNEL[1356289953.228015] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0 (scsi)

KERNEL[1356289953.228063] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/scsi_disk/13:0:0:0 (scsi_disk)

KERNEL[1356289953.228106] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/scsi_device/13:0:0:0 (scsi_device)

KERNEL[1356289953.228152] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/scsi_generic/sg3 (scsi_generic)

KERNEL[1356289953.228200] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/bsg/13:0:0:0 (bsg)

UDEV  [1356289953.228457] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0 (scsi)

UDEV  [1356289953.228914] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0 (scsi)

UDEV  [1356289953.229686] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/scsi_disk/13:0:0:0 (scsi_disk)

UDEV  [1356289953.229745] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/scsi_device/13:0:0:0 (scsi_device)

KERNEL[1356289953.230571] add      /devices/virtual/bdi/8:32 (bdi)

KERNEL[1356289953.230632] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc (block)

UDEV  [1356289953.231371] add      /devices/virtual/bdi/8:32 (bdi)

UDEV  [1356289953.231431] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/bsg/13:0:0:0 (bsg)

UDEV  [1356289953.231485] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/scsi_generic/sg3 (scsi_generic)

KERNEL[1356289953.232967] change   /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc (block)

KERNEL[1356289953.241411] change   /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc (block)

UDEV  [1356289953.248506] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc (block)

UDEV  [1356289953.263452] change   /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc (block)

UDEV  [1356289953.276738] change   /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc (block)
```

and here after 'fdisk -l /dev/sdc' command:

```
KERNEL[1356290122.149694] change   /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc (block)

KERNEL[1356290122.156506] change   /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc (block)

KERNEL[1356290122.156844] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc/sdc1 (block)

UDEV  [1356290122.258834] change   /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc (block)

UDEV  [1356290122.319878] change   /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc (block)

UDEV  [1356290122.414072] add      /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.5/1-1.5:1.0/host13/target13:0:0/13:0:0:0/block/sdc/sdc1 (block)
```

----------

## carlosp

Funny, I have the same behavior. At least the tip about touching /dev/sdc [in my case] solves partially the problem. Please let me know if you founf a solution. I am also with an android phone (2.2).

----------

## GFCCAE6xF

Did any of you have this working before and then it stop?

Thing is, a week or so back I moved from pf-sources to gentoo-sources and decided to go with a new config file, only just now I have needed to use my Android mass storage and I have this exact same issue, opening my file manager as root makes the partitions available and can then be used by my normal user. All other usb mass storage devices work as normal. I'm going to diff an old config (I don't back them up too often) and see if I can see anything that could have caused it. I shall report back if I have any success.

Edit: I keep the previous kernel as backup and forgot it was the pf one, I booted it up and everything works fine. I can't see anything in the configs though, if anyone else could take a look and suggest anything please do: pf.config g2.config

Note: I have kernel config enabled so those are for the kernels, not an older one like I previously mentioned.

Add:

# udevadm monitor results:

```
KERNEL[544.808248] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1 (usb)

KERNEL[544.809328] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0 (usb)

UDEV  [544.809357] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1 (usb)

KERNEL[544.809368] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3 (scsi)

KERNEL[544.809377] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/scsi_host/host3 (scsi_host)

UDEV  [544.809492] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0 (usb)

UDEV  [544.809569] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3 (scsi)

UDEV  [544.809660] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/scsi_host/host3 (scsi_host)

KERNEL[545.810661] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0 (scsi)

KERNEL[545.810698] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0 (scsi)

KERNEL[545.810718] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/scsi_disk/3:0:0:0 (scsi_disk)

KERNEL[545.810805] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/scsi_device/3:0:0:0 (scsi_device)

KERNEL[545.810919] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/scsi_generic/sg2 (scsi_generic)

UDEV  [545.811055] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0 (scsi)

KERNEL[545.811142] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/bsg/3:0:0:0 (bsg)

UDEV  [545.811456] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0 (scsi)

UDEV  [545.811585] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/scsi_disk/3:0:0:0 (scsi_disk)

UDEV  [545.812462] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/scsi_device/3:0:0:0 (scsi_device)

UDEV  [545.812483] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/bsg/3:0:0:0 (bsg)

UDEV  [545.812494] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/scsi_generic/sg2 (scsi_generic)

KERNEL[545.812624] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1 (scsi)

KERNEL[545.812664] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/scsi_disk/3:0:0:1 (scsi_disk)

KERNEL[545.812675] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/scsi_device/3:0:0:1 (scsi_device)

KERNEL[545.812816] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/scsi_generic/sg3 (scsi_generic)

KERNEL[545.812877] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/bsg/3:0:0:1 (bsg)

UDEV  [545.812959] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1 (scsi)

KERNEL[545.813230] add      /devices/virtual/bdi/8:16 (bdi)

UDEV  [545.813424] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/scsi_disk/3:0:0:1 (scsi_disk)

UDEV  [545.813673] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/scsi_generic/sg3 (scsi_generic)

UDEV  [545.813816] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/bsg/3:0:0:1 (bsg)

UDEV  [545.813828] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/scsi_device/3:0:0:1 (scsi_device)

KERNEL[545.813905] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/block/sdb (block)

UDEV  [545.814601] add      /devices/virtual/bdi/8:16 (bdi)

KERNEL[545.815723] add      /devices/virtual/bdi/8:32 (bdi)

KERNEL[545.816077] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/block/sdc (block)

UDEV  [545.816089] add      /devices/virtual/bdi/8:32 (bdi)

KERNEL[545.816837] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/block/sdb (block)

KERNEL[545.817459] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/block/sdc (block)

KERNEL[545.819338] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/block/sdb (block)

UDEV  [545.819689] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/block/sdb (block)

KERNEL[545.820025] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/block/sdc (block)

UDEV  [545.820264] add      /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/block/sdc (block)

UDEV  [545.824241] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/block/sdb (block)

UDEV  [545.827380] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/block/sdb (block)

UDEV  [545.827490] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/block/sdc (block)

UDEV  [545.832956] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/block/sdc (block)

```

After I open up root file manager:

```
KERNEL[589.082295] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/block/sdb (block)

KERNEL[589.088793] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/block/sdb (block)

KERNEL[589.090780] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/block/sdc (block)

KERNEL[589.096544] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/block/sdc (block)

UDEV  [589.285360] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/block/sdb (block)

UDEV  [589.296058] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/block/sdc (block)

UDEV  [589.376655] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:0/block/sdb (block)

UDEV  [589.389063] change   /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0/host3/target3:0:0/3:0:0:1/block/sdc (block)

```

Output of file manager:

```
ray@gentoo ~ % sudo spacefm

udev changed: /dev/sdb

udev changed: /dev/sdc

udev changed: /dev/sdb

udev changed: /dev/sdc

mount changed: /dev/sdc

mount changed: /dev/sdb

```

----------

## s4e8

When you connect the phone, kernel found it as removable device but no media present. When your phone prepared the media, but no method to send media change signal. Kernel will wait and re-detected media after your first access.

The old hal-daemon or some other software would poll removable device, which can trigger the partition scan. Or you can increase usb_storage.delay_use module parameter, and enable android USB storage quickly.

----------

