Bug#996672: linux-image-5.10.0-9-amd64: ite_cir floods syslog with receive overflow warning messages

[Salvatore Bonaccorso <carnil@debian.org>]

Hi Björn,

On Sun, Oct 17, 2021 at 08:51:02AM +0200, Björn Wiberg wrote:
> Package: src:linux
> Version: 5.10.70-1
> Severity: minor
> 
> Starting with inux-image-5.10.0-9-amd64, the ite_cir kernel module appears to massively flood (approximately 80 log entries per second) syslog with messages stating that a receive overflow has occurred:
> 
> /../
> Oct 10 19:31:39 glimmer kernel: [    3.758499] rc rc0: ITE8708 CIR transceiver as /devices/virtual/rc/rc0
> Oct 10 19:31:39 glimmer kernel: [    3.758557] rc rc0: lirc_dev: driver ite-cir registered at minor = 0, raw IR receiver, raw IR transmitter
> Oct 10 19:31:39 glimmer kernel: [    3.758619] input: ITE8708 CIR transceiver as /devices/virtual/rc/rc0/input3
> Oct 10 19:31:39 glimmer kernel: [    3.760191] ite_cir: driver has been successfully loaded
> /../
> Oct 10 20:42:51 glimmer kernel: [ 4276.187105] rc rc0: receive overflow
> Oct 10 20:42:51 glimmer kernel: [ 4276.195016] rc rc0: receive overflow
> /../ (repeated receive overflow messages)
> 
> This always occurs first after the system has been running for some time (approximately 1½ hours).
> 
> The logging of this condition appears to have been added to the source code earlier this year:
> https://lore.kernel.org/lkml/20210510102009.237644288@linuxfoundation.org/
> 
> It appears from the source code that some kind of reset is attempted, however the outcome of this is unknown (and apparently does not succeed and/or solve the receive overflow condition).
> 
> The machine in question is located in a closet with no known IR sending from other devices.
> There are no known applications running that are using the input device (/devices/virtual/rc/rc0/input3).
> 
> Output from lsmod shows the following:
> 
> root@glimmer:~# lsmod | grep -Ei '(ir_|_ir|rc_|_rc|ite)' | grep -v crc
> ir_rc6_decoder         20480  0
> rc_rc6_mce             16384  0
> ite_cir                32768  0
> rc_core                61440  4 ite_cir,ir_rc6_decoder,rc_rc6_mce
> 
> Possible work-arounds include blacklisting the ite_cir module (e.g. in /etc/modprobe.d/local.conf):
> blacklist ite_cir
> 
> ...which would then disable the IR functionality altogether, or to temporarily discard the log messages (e.g. in /etc/rsyslog.d/local.conf):
> if $syslogfacility-text == 'kern' and $programname == 'kernel' and re_match($msg, '\\] rc rc[^:]+: receive overflow$') and $syslogseverity >= 4 then stop
> 
> However this does not solve the underlying problem.
> 
> I understand that the problem could potentially be because of "iffy" hardware, but still wanted to report this, e.g. in case many others are seeing the same thing on their systems.

I assume you get the same logged as well using newer kernel from
unstable (or bullseye-backports, 5.14.9-2~bpo11+1, there are though
not yet signed packages)?

If so it might be best to ask upstream to rule out the iffy hardware
part.

Regards,
Salvatore