Hmm, so the patch that makes MM use +CSIM? errors to determine if the modem is a GSM modem doesn't fix this for us? (i.e. it doesn't also expose the 3gpp interface?)

I'm wondering now why we'd hit that interface for IMEI/MEID when it's exposed on a more general one already, and the +CSIM? patch fixes it there.

The following revision refers to this bug:
  https://chromium.googlesource.com/aosp/platform/system/connectivity/shill/+/1ddcc05a84f8d1172d6048306b60370074db90be

commit 1ddcc05a84f8d1172d6048306b60370074db90be
Author: Ben Chan <benchan@chromium.org>
Date: Sat Dec 30 02:10:21 2017

shill: cellular: use equipment ID when IMEI/MEID isn't available

CL:715179 improved the device storage identifier generation for cellular
devices by using IMEI or MEID, reported by ModemManager, as a unique
device identifier. IMEI is retrieved from the
org.freedesktop.ModemManager1.Modem.Modem3gpp interface and MEID is
retrieved from the org.freedesktop.ModemManager1.Modem.ModemCdma
interface. However, ModemManager doesn't expose the Modem3gpp or
ModemCdma interface if it fails to complete the modem initialization
(e.g. when a SIM is missing). Instead of falling back to use MAC address
when neither IMEI nor MEID is available, this CL modifies shill to use
the equipment ID property reported on the
org.freedesktop.ModemManager1.Modem interface, which is still a better
choice for a unique device identifier than the MAC address.

BUG= chromium:797447 
TEST=Run unit tests.
TEST=Test with a cellular device without a SIM and verify that shill
     creates and uses the same device entry in the profile for the
     device even though the device has a varying MAC address randomly
     generated by the kernel.

Change-Id: I3130fb0febc77a4ad4df145832300b4c91ddac7e
Reviewed-on: https://chromium-review.googlesource.com/843656
Commit-Ready: Ben Chan <benchan@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
Reviewed-by: Ben Chan <benchan@chromium.org>

[modify] https://crrev.com/1ddcc05a84f8d1172d6048306b60370074db90be/cellular/cellular_unittest.cc
[modify] https://crrev.com/1ddcc05a84f8d1172d6048306b60370074db90be/cellular/cellular.cc
[modify] https://crrev.com/1ddcc05a84f8d1172d6048306b60370074db90be/cellular/cellular.h
[modify] https://crrev.com/1ddcc05a84f8d1172d6048306b60370074db90be/cellular/cellular_capability_universal.cc

This bug requires manual review: M64 has already been promoted to the beta branch, so this requires manual review
Please contact the milestone owner if you have questions.
Owners: cmasso@(Android), cmasso@(iOS), kbleicher@(ChromeOS), abdulsyed@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Did #4 get addressed?  Is this a M-64 regression or a nice to have? 

Re #4: Unfortunately no. ModemManager doesn't expose Modem3gpp interface when the SIM is missing.

Re #9: Addressed your question over email

Approving merge to M64 Chrome OS.

The following revision refers to this bug:
  https://chromium.googlesource.com/aosp/platform/system/connectivity/shill/+/bf23013171c9337bf7b1a6a01dddf144b71e3514

commit bf23013171c9337bf7b1a6a01dddf144b71e3514
Author: Ben Chan <benchan@chromium.org>
Date: Thu Jan 04 16:56:28 2018

shill: cellular: use equipment ID when IMEI/MEID isn't available

CL:715179 improved the device storage identifier generation for cellular
devices by using IMEI or MEID, reported by ModemManager, as a unique
device identifier. IMEI is retrieved from the
org.freedesktop.ModemManager1.Modem.Modem3gpp interface and MEID is
retrieved from the org.freedesktop.ModemManager1.Modem.ModemCdma
interface. However, ModemManager doesn't expose the Modem3gpp or
ModemCdma interface if it fails to complete the modem initialization
(e.g. when a SIM is missing). Instead of falling back to use MAC address
when neither IMEI nor MEID is available, this CL modifies shill to use
the equipment ID property reported on the
org.freedesktop.ModemManager1.Modem interface, which is still a better
choice for a unique device identifier than the MAC address.

BUG= chromium:797447 
TEST=Run unit tests.
TEST=Test with a cellular device without a SIM and verify that shill
     creates and uses the same device entry in the profile for the
     device even though the device has a varying MAC address randomly
     generated by the kernel.

Change-Id: I3130fb0febc77a4ad4df145832300b4c91ddac7e
Reviewed-on: https://chromium-review.googlesource.com/843656
Commit-Ready: Ben Chan <benchan@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
Reviewed-by: Ben Chan <benchan@chromium.org>
(cherry picked from commit 1ddcc05a84f8d1172d6048306b60370074db90be)

[modify] https://crrev.com/bf23013171c9337bf7b1a6a01dddf144b71e3514/cellular/cellular_unittest.cc
[modify] https://crrev.com/bf23013171c9337bf7b1a6a01dddf144b71e3514/cellular/cellular.cc
[modify] https://crrev.com/bf23013171c9337bf7b1a6a01dddf144b71e3514/cellular/cellular.h
[modify] https://crrev.com/bf23013171c9337bf7b1a6a01dddf144b71e3514/cellular/cellular_capability_universal.cc

benchan@ - do you need help with testing / verifying this fix? 

This issue has been approved for a merge. Please merge the fix to any appropriate branches as soon as possible!

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This issue has been approved for a merge. Please merge the fix to any appropriate branches as soon as possible!

If all merges have been completed, please remove any remaining Merge-Approved labels from this issue.

Thanks for your time! To disable nags, add the Disable-Nags label.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot