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From: Stefan Hajnoczi <stefanha@gmail.com>
To: "Lluís Vilanova" <vilanova@ac.upc.edu>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Help writing a trivial device
Date: Mon, 26 Sep 2011 08:51:59 +0100	[thread overview]
Message-ID: <20110926075159.GA6455@stefanha-thinkpad.localdomain> (raw)
In-Reply-To: <87litcs1ly.fsf@ginnungagap.bsc.es>

On Mon, Sep 26, 2011 at 12:23:21AM +0200, Lluís Vilanova wrote:
> 1) Cannot start QEMU with KVM when the device is enabled:
>        kvm_set_phys_mem: error registering slot: Invalid argument
> 
> 2) The driver never gets called on a read/write to its memory

If I add #include "pci.h" at the top of the file, change
TARGET_PAGE_SIZE to 4096 (generic device code is not supposed to be
target-dependent), and throw foo.o into Makefile.objs it builds here.

It launches successfully with -enable-kvm and I can see the device
inside a VM.  My qemu.git/HEAD is
1ce9ce6a6184f0192015ba9adf1123d89cd47a7b.

I only had a few minutes and couldn't test reading from BAR0, but you
might want to get 32-bit reads working first before trying 64-bit.

Stefan

  reply	other threads:[~2011-09-26  8:19 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-09-25 22:23 [Qemu-devel] Help writing a trivial device Lluís Vilanova
2011-09-26  7:51 ` Stefan Hajnoczi [this message]
2011-09-26 12:54   ` Lluís Vilanova
2011-09-26 18:03     ` Lluís Vilanova
2011-09-27  7:08       ` Stefan Hajnoczi
2011-09-27 13:03         ` Lluís Vilanova
2011-09-27  6:15     ` Zhi Yong Wu
2011-09-27  6:38     ` Avi Kivity
2011-09-27  6:34 ` Zhi Yong Wu
2011-09-27 13:05   ` Lluís Vilanova

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