linux-kernel - Re: [RFC PATCH v1 05/37] KVM: guest_memfd: Wire up kvm_get_memory

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20260204124715.GA2328995@ziepe.ca>
Date: Wed, 4 Feb 2026 08:47:15 -0400
From: Jason Gunthorpe <jgg@...pe.ca>
To: Xu Yilun <yilun.xu@...ux.intel.com>
Cc: Sean Christopherson <seanjc@...gle.com>,
	Ackerley Tng <ackerleytng@...gle.com>,
	Alexey Kardashevskiy <aik@....com>, cgroups@...r.kernel.org,
	kvm@...r.kernel.org, linux-doc@...r.kernel.org,
	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-kselftest@...r.kernel.org, linux-mm@...ck.org,
	linux-trace-kernel@...r.kernel.org, x86@...nel.org,
	akpm@...ux-foundation.org, binbin.wu@...ux.intel.com, bp@...en8.de,
	brauner@...nel.org, chao.p.peng@...el.com, chenhuacai@...nel.org,
	corbet@....net, dave.hansen@...el.com, dave.hansen@...ux.intel.com,
	david@...hat.com, dmatlack@...gle.com, erdemaktas@...gle.com,
	fan.du@...el.com, fvdl@...gle.com, haibo1.xu@...el.com,
	hannes@...xchg.org, hch@...radead.org, hpa@...or.com,
	hughd@...gle.com, ira.weiny@...el.com, isaku.yamahata@...el.com,
	jack@...e.cz, james.morse@....com, jarkko@...nel.org,
	jgowans@...zon.com, jhubbard@...dia.com, jroedel@...e.de,
	jthoughton@...gle.com, jun.miao@...el.com, kai.huang@...el.com,
	keirf@...gle.com, kent.overstreet@...ux.dev,
	liam.merwick@...cle.com, maciej.wieczor-retman@...el.com,
	mail@...iej.szmigiero.name, maobibo@...ngson.cn,
	mathieu.desnoyers@...icios.com, maz@...nel.org, mhiramat@...nel.org,
	mhocko@...nel.org, mic@...ikod.net, michael.roth@....com,
	mingo@...hat.com, mlevitsk@...hat.com, mpe@...erman.id.au,
	muchun.song@...ux.dev, nikunj@....com, nsaenz@...zon.es,
	oliver.upton@...ux.dev, palmer@...belt.com, pankaj.gupta@....com,
	paul.walmsley@...ive.com, pbonzini@...hat.com, peterx@...hat.com,
	pgonda@...gle.com, prsampat@....com, pvorel@...e.cz,
	qperret@...gle.com, richard.weiyang@...il.com,
	rick.p.edgecombe@...el.com, rientjes@...gle.com,
	rostedt@...dmis.org, roypat@...zon.co.uk, rppt@...nel.org,
	shakeel.butt@...ux.dev, shuah@...nel.org, steven.price@....com,
	steven.sistare@...cle.com, suzuki.poulose@....com, tabba@...gle.com,
	tglx@...utronix.de, thomas.lendacky@....com, vannapurve@...gle.com,
	vbabka@...e.cz, viro@...iv.linux.org.uk, vkuznets@...hat.com,
	wei.w.wang@...el.com, will@...nel.org, willy@...radead.org,
	wyihan@...gle.com, xiaoyao.li@...el.com, yan.y.zhao@...el.com,
	yilun.xu@...el.com, yuzenghui@...wei.com, zhiquan1.li@...el.com
Subject: Re: [RFC PATCH v1 05/37] KVM: guest_memfd: Wire up
 kvm_get_memory_attributes() to per-gmem attributes

On Wed, Feb 04, 2026 at 12:43:16PM +0800, Xu Yilun wrote:
> > Which means we need VFIO to know what they are, and hopefully it is
> > just static based on the TDISP reports..
> 
> I don't think VMM need to check TDISP report. The only special thing is
> the MSI-X mixed pages which can be figured out by standard PCI
> discovery.

Either that or follow along with the guests's choices on
shared/private.

We can't let VFIO mmap a private MMIO page, so it has to know which
pages are private at any moment, and it can't guess.

Jason