From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <d67c46cd156233f61e9381a31c62269d@rei2.9hal>
Date: Thu, 23 Aug 2012 18:18:58 +0200
From: cinap_lenrek@gmx.de
To: 9fans@9fans.net
In-Reply-To: <adc1112371236b29958172a8c9fe2afe@brasstown.quanstro.net>
MIME-Version: 1.0
Content-Type: text/plain; charset="US-ASCII"
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Subject: Re: [9fans] devmnt crash, fix.
Topicbox-Message-UUID: aeee63a6-ead7-11e9-9d60-3106f5b1d025

pwait():

...

	sleep(&up->waitr, haswaitq, up);

	lock(&up->exl);
	wq = up->waitq;
	up->waitq = wq->next;	<-- wq == nil, boom! its gone!
	up->nwait--;
	unlock(&up->exl);


if sleep returns or is spuriously woken up even tho up->waitq == nil.

--
cinap