From: Stefan Hajnoczi <stefanha@gmail.com>
To: BALATON Zoltan <balaton@eik.bme.hu>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Debugging io deadlock
Date: Fri, 8 Dec 2017 11:01:44 +0000 [thread overview]
Message-ID: <20171208110144.GI23880@stefanha-x1.localdomain> (raw)
In-Reply-To: <alpine.BSF.2.21.1712051856040.96903@zero.eik.bme.hu>
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On Tue, Dec 05, 2017 at 07:35:36PM +0100, BALATON Zoltan wrote:
> On Tue, 5 Dec 2017, Stefan Hajnoczi wrote:
> > On Mon, Dec 04, 2017 at 08:22:48PM +0100, BALATON Zoltan wrote:
> I don't really know what to look for
> so if anyone has any more ideas then please share.
I don't have a specific idea, but two general techniques for debugging
guest hangs:
1. Enable tracing or add printfs to monitor hardware register writes and
interrupts. This way you can figure out which devices were most
recently accessed. They are probably involved in the hang.
2. Peek at QEMU device state from GDB. For example, look at virtio
device vrings to see which requests are currently in-flight.
Stefan
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prev parent reply other threads:[~2017-12-08 11:01 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-04 19:22 [Qemu-devel] Debugging io deadlock BALATON Zoltan
2017-12-05 13:54 ` Stefan Hajnoczi
2017-12-05 18:35 ` BALATON Zoltan
2017-12-08 11:01 ` Stefan Hajnoczi [this message]
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