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Date: Fri, 8 Jan 2016 20:04:03 +0100
From: Marius Strobl <marius@alchemy.franken.de>
To: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Cc: Kurt Lidl <lidl@pix.net>, freebsd-sparc64@freebsd.org,
 FreeBSD-Current <freebsd-current@freebsd.org>
Subject: Re: sparc64 traps during probe (r293243)
Message-ID: <20160108190403.GB87189@alchemy.franken.de>
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On Fri, Jan 08, 2016 at 04:57:58PM +0000, Mark Cave-Ayland wrote:
> On 08/01/16 15:42, Kurt Lidl wrote:
> 
> This looks amazingly similar to what I get trying to boot FreeBSD under
> QEMU, i.e. pointing at sched_clock():
> 

<...>

> -- kernel stack fault %o7=0xc011a050 --
> panic: longjmp botch
> cpuid = -1012475520
> KDB: stack backtrace:
> Uptime: 3s
> 
> Note also the "longjmp botch" error right at the end. This is with the
> sun4u timer fix patch developed with help from Marius which has recently
> been applied to QEMU git master. So maybe this is a kernel bug after all?

No, that still is a completely trashed kernel stack as previously
seen when running under QEMU so the whole backtrace is questionable.
Apart from that, sched_clock() is called rather frequently so it is
not unlikely to show up in a kernel back trace but neither of the
two back traces in question suggest it's the culprit (assuming that
the one seen with QEMU actually is sane).

Marius