linux-kernel - Re: [PATCH v4 2/5] KVM: arm64: Make stage2_has

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:
 <SA1PR12MB71996C0BCE42A80D60D9384CB09EA@SA1PR12MB7199.namprd12.prod.outlook.com>
Date: Wed, 21 May 2025 00:50:04 +0000
From: Ankit Agrawal <ankita@...dia.com>
To: Oliver Upton <oliver.upton@...ux.dev>
CC: Jason Gunthorpe <jgg@...dia.com>, "maz@...nel.org" <maz@...nel.org>,
	"joey.gouly@....com" <joey.gouly@....com>, "suzuki.poulose@....com"
	<suzuki.poulose@....com>, "yuzenghui@...wei.com" <yuzenghui@...wei.com>,
	"catalin.marinas@....com" <catalin.marinas@....com>, "will@...nel.org"
	<will@...nel.org>, "ryan.roberts@....com" <ryan.roberts@....com>,
	"shahuang@...hat.com" <shahuang@...hat.com>, "lpieralisi@...nel.org"
	<lpieralisi@...nel.org>, "david@...hat.com" <david@...hat.com>, Aniket Agashe
	<aniketa@...dia.com>, Neo Jia <cjia@...dia.com>, Kirti Wankhede
	<kwankhede@...dia.com>, Krishnakant Jaju <kjaju@...dia.com>, "Tarun Gupta
 (SW-GPU)" <targupta@...dia.com>, Vikram Sethi <vsethi@...dia.com>, Andy
 Currid <acurrid@...dia.com>, Alistair Popple <apopple@...dia.com>, John
 Hubbard <jhubbard@...dia.com>, Dan Williams <danw@...dia.com>, Zhi Wang
	<zhiw@...dia.com>, Matt Ochs <mochs@...dia.com>, Uday Dhoke
	<udhoke@...dia.com>, Dheeraj Nigam <dnigam@...dia.com>,
	"alex.williamson@...hat.com" <alex.williamson@...hat.com>,
	"sebastianene@...gle.com" <sebastianene@...gle.com>, "coltonlewis@...gle.com"
	<coltonlewis@...gle.com>, "kevin.tian@...el.com" <kevin.tian@...el.com>,
	"yi.l.liu@...el.com" <yi.l.liu@...el.com>, "ardb@...nel.org"
	<ardb@...nel.org>, "akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
	"gshan@...hat.com" <gshan@...hat.com>, "linux-mm@...ck.org"
	<linux-mm@...ck.org>, "ddutile@...hat.com" <ddutile@...hat.com>,
	"tabba@...gle.com" <tabba@...gle.com>, "qperret@...gle.com"
	<qperret@...gle.com>, "seanjc@...gle.com" <seanjc@...gle.com>,
	"kvmarm@...ts.linux.dev" <kvmarm@...ts.linux.dev>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-arm-kernel@...ts.infradead.org"
	<linux-arm-kernel@...ts.infradead.org>, "maobibo@...ngson.cn"
	<maobibo@...ngson.cn>
Subject: Re: [PATCH v4 2/5] KVM: arm64: Make stage2_has_fwb global scope

>>
>> Change the scope of stage2_has_fwb as it will be used in
>> broader KVM code to determine whether the FWB feature is
>> supported by the hardware.
>
> Please just use the cpucap directly outside of the page table code. The
> only non-FWB stage-2 that KVM maintains on a FEAT_S2FWB machine is for
> the host when using protected mode. I don't anticipate that changing any
> time soon.

Thanks Oliver for reviewing the change.

I'll remove this patch and make the change to use
cpus_have_final_cap(ARM64_HAS_STAGE2_FWB) instead of stage2_has_fwb()
in the next version.

> Thanks,
> Oliver