From: Gleb Natapov <gleb@redhat.com>
To: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>,
Avi Kivity <avi@redhat.com>, LKML <linux-kernel@vger.kernel.org>,
KVM <kvm@vger.kernel.org>
Subject: Re: [PATCH] KVM: fix async page fault working for readonly mapping
Date: Tue, 22 May 2012 08:31:10 +0300 [thread overview]
Message-ID: <20120522053110.GT10209@redhat.com> (raw)
In-Reply-To: <20120521193041.GA25940@amt.cnet>
On Mon, May 21, 2012 at 04:30:41PM -0300, Marcelo Tosatti wrote:
> On Mon, May 21, 2012 at 04:15:50PM +0800, Xiao Guangrong wrote:
> > On 05/21/2012 04:08 PM, Gleb Natapov wrote:
> >
> > > On Mon, May 21, 2012 at 02:45:45PM +0800, Xiao Guangrong wrote:
> > >> If we map a readonly memory space from host to guest and the page is
> > >> not currently mapped in the host, we will get a fault-pfn and async
> > >> is not allowed, then the vm will crash
> > >>
> > > Why would we want to map a readonly memory space from host to guest?
> > > We may want to do it to support memory semantics on read and mmio on
> > > write, but do not right now unless something changed while I was not
> > > looking.
> >
> >
> > Some test cases in kvm-unit-tests and the benchmark i am writing for KVM
> > need map the function on host to guest.
>
> Or ROM. Or read-only mappings of IVSHMEM (which don't exist yet).
True. KVM should ignore writes to such areas, not kill a guest. Is this
how the code works today?
--
Gleb.
next prev parent reply other threads:[~2012-05-22 5:31 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-21 6:45 [PATCH] KVM: fix async page fault working for readonly mapping Xiao Guangrong
2012-05-21 8:08 ` Gleb Natapov
2012-05-21 8:15 ` Xiao Guangrong
2012-05-21 19:30 ` Marcelo Tosatti
2012-05-22 5:31 ` Gleb Natapov [this message]
2012-05-22 14:27 ` Avi Kivity
2012-05-23 3:09 ` Xiao Guangrong
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