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From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Fri, 24 Nov 2017 13:44:23 +0100
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Subject: Re: [Qemu-devel] KVM "fake DAX" flushing interface - discussion
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To: Pankaj Gupta <pagupta@redhat.com>, Dan Williams <dan.j.williams@intel.com>, Rik van Riel <riel@redhat.com>, Xiao Guangrong <xiaoguangrong.eric@gmail.com>, Christoph Hellwig <hch@infradead.org>
Cc: Jan Kara <jack@suse.cz>, Stefan Hajnoczi <stefanha@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, kvm-devel <kvm@vger.kernel.org>, Qemu Developers <qemu-devel@nongnu.org>, "linux-nvdimm@lists.01.org" <linux-nvdimm@ml01.01.org>, ross zwisler <ross.zwisler@linux.intel.com>, Kevin Wolf <kwolf@redhat.com>, Nitesh Narayan Lal <nilal@redhat.com>, Haozhong Zhang <haozhong.zhang@intel.com>, Ross Zwisler <ross.zwisler@intel.com>

On 24/11/2017 13:40, Pankaj Gupta wrote:
>    - Suggestion by Paolo & Stefan(previously) to use virtio-blk makes sense if just 
>      want a flush vehicle to send guest commands to host and get reply after asynchronous
>      execution. There was previous discussion [1] with Rik & Dan on this.
> 
>     [1] https://lists.gnu.org/archive/html/qemu-devel/2017-07/msg08373.html 

... in fact, the virtio-blk device _could_ actually accept regular I/O
too.  That would make it easier to boot from pmem.  Is there anything
similar in regular hardware?

Paolo