From:   Sergey Matyukevich <sergey.matyukevich.os@quantenna.com>
To:     "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>
CC:     Igor Mitsyanko <igor.mitsyanko.os@quantenna.com>
Subject: question: crda timeout in cfg80211
Thread-Topic: question: crda timeout in cfg80211
Thread-Index: AQHU49FXR0CTE3RHB0aq9jc7wfrsmA==
Date:   Tue, 26 Mar 2019 12:42:15 +0000
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Hi all,

Linux cfg80211 regulatory subsystem uses CRDA timeout to ensure completion
of regulatory updates, performed by user-space software. See call_crda
functon in net/wireless/reg.c:

static int call_crda(const char *alpha2)
{
	...

	queue_delayed_work(system_power_efficient_wq,
			&crda_timeout, msecs_to_jiffies(3142));
	return 0;
}

So regulatory update/reset operations shall be completed in 3142 msec.
And that includes processing of regulatory notifiers for all the
wireless cards in the system.

It is not quite clear where this specific timeout value came from.
Original commit (a90c7a313a1c5b) doesn't go into details about it.

Any ideas where it could come from ?

Regards,
Sergey