evilsocket/pwnagotchi

nexmon blindness bug (brcmf_cfg80211_nexmon_set_channel)

Open

#267 opened on Oct 12, 2019

View on GitHub
 (96 comments) (0 reactions) (1 assignee)JavaScript (978 forks)batch import
bughacktoberfesthardwarehelp wanted

Repository metrics

Stars
 (6,243 stars)
PR merge metrics
 (No merged PRs in 30d)

Description

every once in a while, nexmon dies with:

[ 4341.527847] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4101, -110
[ 4344.327806] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4097, -110
[ 4347.127853] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4098, -110
[ 4349.927917] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4099, -110
[ 4352.728074] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4100, -110
[ 4355.527970] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4101, -110
[ 4358.328022] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4102, -110
[ 4361.208095] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4103, -110
[ 4364.008157] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4104, -110
[ 4366.808218] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4105, -110
[ 4369.608431] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4097, -110
[ 4372.408345] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4098, -110
[ 4375.288408] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4099, -110
[ 4378.088474] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4100, -110
[ 4380.891399] brcmfmac: brcmf_cfg80211_nexmon_set_channel: Set Channel failed: chspec=4101, -110

And only a reboot can fix the wifi, this is why the mon_max_blind_epochs parameter exists, to reboot the board when this happens.

Ideally we should document this known issue, the configuration and some day maybe fix it.

Contributor guide

Research direction
Investigate why brcmf cfg80211 nexmon set channel returns 110 (ETIMEDOUT). Examine the interaction between nexmon firmware and brcmfmac driver, check for race conditions or hardware issues.
Tech stack
c
Domain
embedded iotoperating systems
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
3-5 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Needs investigation
Prerequisites
CLinux kernel debugging
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
25