[FS#527] QMI modem Olivetti Techcenter (0b3c:c00a) freezes on uqmi --sync call (never connects)

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - Luiz Angelo Daros de Luca (luizluca) 

Attached to Project - LEDE Project
Summary - QMI modem Olivetti Techcenter (0b3c:c00a) freezes on uqmi --sync call (never connects)
Task Type - Bug Report
Category - Packages
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Medium
Priority - Very Low
Reported Version - lede-17.01
Due in Version - Undecided
Due Date - Undecided
Details - Hello,

I used to use modem Olivetti Techcenter (0b3c:c00a) on OpenWRT CC.1 without problems.
However, testing on LEDE 17.01.0-rc2, I'm unable to connect.

I traced the problem to 'uqmi -s -d "$device" --sync' at [[https://github.com/lede-project/source/blob/master/package/network/utils/uqmi/files/lib/netifd/proto/qmi.sh#L101]].

My config is simple as:


config interface 'wwan'
        option ifname 'wwan0'
        option proto 'qmi'
        option device '/dev/cdc-wdm0'
        option apn 'gprs.oi.com.br'
        option auth 'none'


Using strace, it always stops at this point:


...
open("/dev/cdc-wdm0", O_RDWR|O_EXCL|O_NOCTTY|O_NONBLOCK|O_LARGEFILE) = 6
fcntl64(6, F_GETFL)                     = 0x2082 (flags O_RDWR|O_NONBLOCK|O_LARGEFILE)
fcntl64(6, F_SETFL, O_RDWR|O_NONBLOCK|O_LARGEFILE) = 0
epoll_ctl(3, EPOLL_CTL_ADD, 6, {EPOLLIN|EPOLLRDHUP|EPOLLET, {u32=4305304, u64=18491139879337984}}) = 0
write(6, "\1\v\0\0\0\0\0\1'\0\0\0", 12) = 12
rt_sigaction(SIGINT, NULL, {sa_handler=0x401071, sa_mask=[RT_66 RT_67 RT_68 RT_69 RT_70 RT_71], sa_flags=SA_RESTORER|SA_RESTART, sa_restorer=0}, 16) = 0
rt_sigaction(SIGTERM, NULL, {sa_handler=0x401071, sa_mask=[RT_66 RT_67 RT_68 RT_69 RT_70 RT_71], sa_flags=SA_RESTORER|SA_RESTART, sa_restorer=0}, 16) = 0
rt_sigaction(SIGCHLD, NULL, {sa_handler=SIG_DFL, sa_mask=[RT_66 RT_67 RT_68 RT_69 RT_70 RT_71], sa_flags=0}, 16) = 0
rt_sigaction(SIGCHLD, {sa_handler=0x77d85541, sa_mask=[RT_68 RT_69 RT_73 RT_74 RT_75 RT_76 RT_78 RT_80 RT_82 RT_84 RT_85 RT_87 RT_88 RT_89 RT_90 RT_91 RT_93 RT_94 RT_95], sa_flags=SA_RESTORER, sa_restorer=0}, NULL, 16) = 0
rt_sigaction(SIGPIPE, NULL, {sa_handler=SIG_DFL, sa_mask=[RT_65 RT_68 RT_70], sa_flags=0}, 16) = 0
rt_sigaction(SIGPIPE, {sa_handler=SIG_IGN, sa_mask=[RT_68 RT_69 RT_73 RT_74 RT_75 RT_76 RT_78 RT_80 RT_82 RT_84 RT_85 RT_87 RT_88 RT_89 RT_90 RT_91 RT_93 RT_94 RT_95], sa_flags=SA_RESTORER, sa_restorer=0}, NULL, 16) = 0
clock_gettime(CLOCK_MONOTONIC, {tv_sec=7909, tv_nsec=543507701}) = 0
clock_gettime(CLOCK_MONOTONIC, {tv_sec=7909, tv_nsec=544052152}) = 0
epoll_pwait(3, 


If I comment the "uqmi --sync" call, it simply works. "--sync" is a new action for uqmi since OpenWRT CC.1

My System is:
  
LEDE 17.01.0-rc2, r3131-42f3c1f
uqmi 2016-12-19-8ceeab69-1
machine: TP-LINK TL-WDR3600/4300/4310 (ar71xx) with QMI modem Olivetti Techcenter (0b3c:c00a) 







More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=527