Re: [PATCH v5 0/7] Add QMI Device Service Request Rate-limit Option

Hi Grant,

On 2/17/25 2:01 PM, Grant Erickson wrote:
> Certain modems, among them the Quectel Wireless Solutions Co.,
> Ltd. (2c7c) BG96 CAT-M1/NB-IoT modem (0296), have a firmware issue
> where they can lock up and hang (not responding to subsequent
> commands) due to high QMI service request arrival rates.
> 
> QMI service request rate limiting is achieved by:
> 
> 1. Adding a new, optional options structure to qmi_qmux_device_new
>     that has its rate-limit "quirk" and minimum request period fields
>     set when the modem "RequestThrottleTimeUs" integer property is set.
> 
> 2. Adding logic to the QMI driver that, when a minimum request period
>     is set, limits the QMI service request rate accordingly.
> 
> (1) and (2) are used by the udevng and gobi plugins such that when the
> modem vendor and model match 2c7c/0296, then the option to rate limit
> QMI service requests is set to no more than one every 2,000 us.
> 
> Grant Erickson (7):
>    qmi: Added enumeration for device quirk flags.
>    qmi: Added structure for device options.
>    qmi: Added device options parameter to 'qmi_qmux_device_new'.
>    qmi: Implement QMI service request rate limiting in 'can_write_data'.
>    qmi: Handle request rate limit option in 'qmi_qmux_device_new'.
>    udevng: Set the QMI minimum service request period for Quectel BG96
>      modems.
>    gobi: Pass QMI qmux device options to 'qmi_qmux_device_new'.
> 
>   drivers/qmimodem/qmi.c | 51 +++++++++++++++++++++++++++++++++++++++++-
>   drivers/qmimodem/qmi.h | 40 ++++++++++++++++++++++++++++++++-
>   plugins/gobi.c         | 22 +++++++++++++++++-
>   plugins/udevng.c       | 14 ++++++++++++
>   4 files changed, 124 insertions(+), 3 deletions(-)
> 

Alpine (musl) gcc debug
=======================
Configure: PASS
Build: FAIL
     drivers/qmimodem/qmi.c: In function 'can_write_data':
     drivers/qmimodem/qmi.c:701:1: error: unknown option after '#pragma GCC 
diagnostic' kind [-Werror=pragmas]
       701 | _Pragma("GCC diagnostic ignored \"-Wconditional-uninitialized\"")
           | ^~~~~~~
     drivers/qmimodem/qmi.c:701:1: note: did you mean '-Wno-uninitialized'?
     cc1: all warnings being treated as errors
     make[1]: *** [Makefile:4090: drivers/qmimodem/qmi.o] Error 1
     make[1]: Target 'all-am' not remade because of errors.
     make: *** [Makefile:2405: all] Error 2

Fedora (glibc) clang debug+sanitizers
=====================================
Configure: PASS
Build: PASS
Unit: PASS
Distcheck: PASS

Alpine (musl) gcc optimized
===========================
Configure: PASS
Build: FAIL
     drivers/qmimodem/qmi.c: In function 'can_write_data':
     drivers/qmimodem/qmi.c:701:1: error: unknown option after '#pragma GCC 
diagnostic' kind [-Werror=pragmas]
       701 | _Pragma("GCC diagnostic ignored \"-Wconditional-uninitialized\"")
           | ^~~~~~~
     drivers/qmimodem/qmi.c:701:1: note: did you mean '-Wno-uninitialized'?
     drivers/qmimodem/qmi.c:703:50: error: 'now' may be used uninitialized 
[-Werror=maybe-uninitialized]
       703 |                 transport->last_req_sent_time_us = now;
           |                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~
     drivers/qmimodem/qmi.c:669:18: note: 'now' was declared here
       669 |         uint64_t now;
           |                  ^~~
     cc1: all warnings being treated as errors
     make[1]: *** [Makefile:4090: drivers/qmimodem/qmi.o] Error 1
     make[1]: Target 'all-am' not remade because of errors.
     make: *** [Makefile:2405: all] Error 2

Regards,
-Denis