linux-kernel - Re: [RFC PATCH 09/21] KVM: TDX: Enable 2MB mapping size after TD is RUNNABLE

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

Message-ID: <aEt/ohRVsdjKuqFp@yzhao56-desk.sh.intel.com>
Date: Fri, 13 Jun 2025 09:32:18 +0800
From: Yan Zhao <yan.y.zhao@...el.com>
To: "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
CC: "seanjc@...gle.com" <seanjc@...gle.com>, "quic_eberman@...cinc.com"
	<quic_eberman@...cinc.com>, "Li, Xiaoyao" <xiaoyao.li@...el.com>, "Huang,
 Kai" <kai.huang@...el.com>, "Du, Fan" <fan.du@...el.com>, "Hansen, Dave"
	<dave.hansen@...el.com>, "david@...hat.com" <david@...hat.com>,
	"thomas.lendacky@....com" <thomas.lendacky@....com>, "Li, Zhiquan1"
	<zhiquan1.li@...el.com>, "Shutemov, Kirill" <kirill.shutemov@...el.com>,
	"michael.roth@....com" <michael.roth@....com>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>, "Weiny, Ira" <ira.weiny@...el.com>, "Peng,
 Chao P" <chao.p.peng@...el.com>, "pbonzini@...hat.com" <pbonzini@...hat.com>,
	"Yamahata, Isaku" <isaku.yamahata@...el.com>, "ackerleytng@...gle.com"
	<ackerleytng@...gle.com>, "vbabka@...e.cz" <vbabka@...e.cz>,
	"kvm@...r.kernel.org" <kvm@...r.kernel.org>, "binbin.wu@...ux.intel.com"
	<binbin.wu@...ux.intel.com>, "tabba@...gle.com" <tabba@...gle.com>,
	"Annapurve, Vishal" <vannapurve@...gle.com>, "jroedel@...e.de"
	<jroedel@...e.de>, "Miao, Jun" <jun.miao@...el.com>, "pgonda@...gle.com"
	<pgonda@...gle.com>, "x86@...nel.org" <x86@...nel.org>
Subject: Re: [RFC PATCH 09/21] KVM: TDX: Enable 2MB mapping size after TD is
 RUNNABLE

On Fri, Jun 13, 2025 at 08:47:28AM +0800, Edgecombe, Rick P wrote:
> On Thu, 2025-06-12 at 17:44 -0700, Sean Christopherson wrote:
> > > Maybe an "I can handle it" accept size bit that comes in the exit
> > > qualification?

Dynamic turning on "I can handle it" would still require the supporting of
demotion in the fault path because there may be existing huge pages when
an EPT violation without "I can handle it" comes.

> > Eww, no.  Having to react on _every_ EPT violation would be annoying, and
> > trying
> > to debug issues where the guest is mixing options would probably be a
> > nightmare.
> > 
> > I was thinking of something along the lines of an init-time or boot-time opt-
> > in.
> 
> Fair.

Agreed.