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Date: Sun, 4 Mar 2012 20:33:40 +0800
From: WanPeng Li <liwp@linux.vnet.ibm.com>
Message-ID: <20120304123140.GA1760@liwp@linux.vnet.ibm.com>
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Subject: [Qemu-devel] questions about pci
Reply-To: WanPeng Li <liwp@linux.vnet.ibm.com>
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To: qemu-devel <qemu-devel@nongnu.org>

Hi all:

I read pci code in qemu about i440fx, pci.c and so on. I think if guest
os whose mainboard is based on x86, it will use IO instructions to
access PCI configuration space.If not use passthrough, qemu should
emulate these operations.I find a function called kvm_handle_io who will
emulate ioport write/read, I have traced this function, but I haven't found it has
any relationship with pci read/write configuration space functions like
i440fx_write_config and piix3_write_config.So how does it emulate pci
configuration space access when not use passthrough?


thanks 
Wanpeng Li

LTC China, IBM