From: Sean Christopherson <seanjc@google.com>
To: David Woodhouse <dwmw2@infradead.org>
Cc: David Matlack <dmatlack@google.com>,
Brendan Jackman <jackmanb@google.com>,
James Gowans <jgowans@amazon.com>,
"akpm@linux-foundation.org" <akpm@linux-foundation.org>,
Patrick Roy <roypat@amazon.co.uk>,
"chao.p.peng@linux.intel.com" <chao.p.peng@linux.intel.com>,
Derek Manwaring <derekmn@amazon.com>,
"rppt@kernel.org" <rppt@kernel.org>,
"pbonzini@redhat.com" <pbonzini@redhat.com>,
Nikita Kalyazin <kalyazin@amazon.co.uk>,
"lstoakes@gmail.com" <lstoakes@gmail.com>,
"Liam.Howlett@oracle.com" <Liam.Howlett@oracle.com>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
"kirill.shutemov@linux.intel.com"
<kirill.shutemov@linux.intel.com>,
"vbabka@suse.cz" <vbabka@suse.cz>,
"mst@redhat.com" <mst@redhat.com>,
"somlo@cmu.edu" <somlo@cmu.edu>, Alexander Graf <graf@amazon.de>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
"linux-coco@lists.linux.dev" <linux-coco@lists.linux.dev>
Subject: Re: Unmapping KVM Guest Memory from Host Kernel
Date: Fri, 8 Mar 2024 14:47:36 -0800 [thread overview]
Message-ID: <ZeuVV3Jo31lcL41H@google.com> (raw)
In-Reply-To: <aa50a5ea6dbcd5f3f1df39dcf2fc4f5ee881ec8e.camel@infradead.org>
On Fri, Mar 08, 2024, David Woodhouse wrote:
> On Fri, 2024-03-08 at 09:35 -0800, David Matlack wrote:
> > I think what James is looking for (and what we are also interested
> > in), is _eliminating_ the ability to access guest memory from the
> > direct map entirely. And in general, eliminate the ability to access
> > guest memory in as many ways as possible.
>
> Well, pKVM does that...
Out-of-tree :-)
I'm not just being snarky; when pKVM lands this functionality upstream, I fully
expect zapping direct map entries to be generic guest_memfd functionality that
would be opt-in, either by the in-kernel technology, e.g. pKVM, or by userspace,
or by some combination of the two, e.g. I can see making it optional to nuke the
direct map when using guest_memfd for TDX guests so that rogue accesses from the
host generate synchronous #PFs instead of latent #MCs.
next prev parent reply other threads:[~2024-03-08 22:48 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <AQHacXBJeX10YUH0O0SiQBg1zQLaEw==>
2024-03-08 15:50 ` Unmapping KVM Guest Memory from Host Kernel Gowans, James
2024-03-08 16:25 ` Brendan Jackman
2024-03-08 17:35 ` David Matlack
2024-03-08 17:45 ` David Woodhouse
2024-03-08 22:47 ` Sean Christopherson [this message]
2024-03-09 2:45 ` Manwaring, Derek
2024-03-18 14:11 ` Brendan Jackman
2024-03-08 23:22 ` Sean Christopherson
2024-03-09 11:14 ` Mike Rapoport
2024-05-13 10:31 ` Patrick Roy
2024-05-13 15:39 ` Sean Christopherson
2024-05-13 16:01 ` Gowans, James
2024-05-13 17:09 ` Sean Christopherson
2024-05-13 19:43 ` Gowans, James
2024-05-13 20:36 ` Sean Christopherson
2024-05-13 22:01 ` Manwaring, Derek
2024-03-14 21:45 ` Manwaring, Derek
2024-03-09 5:01 ` Matthew Wilcox
2024-03-08 21:05 Manwaring, Derek
2024-03-11 9:26 ` Fuad Tabba
2024-03-11 9:29 ` Fuad Tabba
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