linux-kernel - Re: KVM: arm64: vgic-its: Return -ENXIO to invalid KVM_DEV_ARM_VGIC_GRP

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: <55346a73-d20e-494a-a287-6874216457c8@redhat.com>
Date: Tue, 24 Jun 2025 11:20:10 +0200
From: Eric Auger <eauger@...hat.com>
To: David Woodhouse <dwmw2@...radead.org>, Marc Zyngier <maz@...nel.org>,
 Oliver Upton <oliver.upton@...ux.dev>, Joey Gouly <joey.gouly@....com>,
 Suzuki K Poulose <suzuki.poulose@....com>, Zenghui Yu
 <yuzenghui@...wei.com>, Catalin Marinas <catalin.marinas@....com>,
 Will Deacon <will@...nel.org>, Jing Zhang <jingzhangos@...gle.com>,
 Kunkun Jiang <jiangkunkun@...wei.com>, Paolo Bonzini <pbonzini@...hat.com>,
 Sebastian Ott <sebott@...hat.com>, Maxim Levitsky <mlevitsk@...hat.com>,
 Keisuke Nishimura <keisuke.nishimura@...ia.fr>,
 linux-arm-kernel@...ts.infradead.org, kvmarm@...ts.linux.dev,
 linux-kernel@...r.kernel.org
Subject: Re: KVM: arm64: vgic-its: Return -ENXIO to invalid
 KVM_DEV_ARM_VGIC_GRP_CTRL attrs

Hi David,

On 6/24/25 11:01 AM, David Woodhouse wrote:
> On Tue, 2025-06-24 at 09:25 +0200, Eric Auger wrote:
>> Hi David,
>>
>> On 6/23/25 3:22 PM, David Woodhouse wrote:
>>> From: David Woodhouse <dwmw@...zon.co.uk>
>>>
>>> A preliminary version of a hack to invoke unmap_all_vpes() from an ioctl
>>> didn't work very well. We eventually determined this was because we were
>>> invoking it on the wrong file descriptor, but not getting an error.
>>>
>>> Signed-off-by: David Woodhouse <dwmw@...zon.co.uk>
>>
>> In the corresponding doc (virt/kvm/devices/arm-vgic-its.rst)
>> it is said about possible returned values:
>>      -ENXIO  ITS not properly configured as required prior to setting
>>              this attribute
>> which does not exactly match your situation. Shouldn't we also update
>> the doc or change the returned value?
> 
> Hi Eric, thanks for looking at this.
> 
> I think this is OK because the -ENXIO return is covered by the high-
> level description of KVM_[GS]ET_DEVICE_ATTR in virt/kvm/api.rst:
> 
> Errors:
> 
>   =====   =============================================================
>   ENXIO   The group or attribute is unknown/unsupported for this device
>           or hardware support is missing.
> 

Ah OK I missed that. Anyway that's not a big deal I think.

Reviewed-by: Eric Auger <eric.auger@...hat.com>

Eric