RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Description of problem:
ModemManager is crashing when probing if there are multiple ttyUSB* devices (ttyUSB0 and ttyUSB1 in this case). 
The driver used here is 'cp210x'. During the use of minicom application on /tty/USB0, ModemManager crash is displayed.

When minicom first starts up it seems that before modemmanager quits, we get a lot of gibberish from that tty.

ERROR:mm-port-probe.c:1289:mm_port_probe_run: assertion failed: (self->priv->task == NULL)

Version-Release number of selected component (if applicable):
Red Hat Enterprise Linux Workstation release 7.1
ModemManager-1.1.0-6.git20130913.el7.x86_64

How reproducible:
Always

Steps to Reproduce:
1. Use of minicom program on /tty/USB0
2.
3.

Actual results:
ModemManager crash with below error.
ERROR:mm-port-probe.c:1289:mm_port_probe_run: assertion failed: (self->priv->task == NULL)

Expected results:
No crashes or errors.

Additional info:
ABT Server link : https://api.access.redhat.com/rs/telemetry/abrt/reports/bthash/671de6a93a6e76f8612c45a228276534a35db51c

Blacklisting the device with '/lib/udev/rules.d/100-mm-usb-device-blacklist.rules' didn't work after which the device nodes (/dev/ttyUSB*) aren't created.

ACTION!="add|change", GOTO="mm_usb_device_blacklist_end"
SUBSYSTEM!="usb", GOTO="mm_usb_device_blacklist_end"
ENV{DEVTYPE}!="usb_device",  GOTO="mm_usb_device_blacklist_end"

ATTRS{idVendor}=="10c4", ATTRS{idProduct}=="ea70", ENV{ID_MM_DEVICE_IGNORE}="1"

LABEL="mm_usb_device_blacklist_end"

The forced-close fix in fd1a1839ae1bcade2f9d422f6bc0d6e6040295e6 would avoid the repeated and unnecessary probes that lead to the crash.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHEA-2016-2556.html