linux-kernel - Re: [RFC PATCH v2 55/58] drivers/iommu: Add deferred map

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: <20250102201831.GB26854@ziepe.ca>
Date: Thu, 2 Jan 2025 16:18:31 -0400
From: Jason Gunthorpe <jgg@...pe.ca>
To: Mostafa Saleh <smostafa@...gle.com>
Cc: Robin Murphy <robin.murphy@....com>, iommu@...ts.linux.dev,
	kvmarm@...ts.linux.dev, linux-kernel@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, catalin.marinas@....com,
	will@...nel.org, maz@...nel.org, oliver.upton@...ux.dev,
	joey.gouly@....com, suzuki.poulose@....com, yuzenghui@...wei.com,
	robdclark@...il.com, joro@...tes.org, jean-philippe@...aro.org,
	nicolinc@...dia.com, vdonnefort@...gle.com, qperret@...gle.com,
	tabba@...gle.com, danielmentz@...gle.com, tzukui@...gle.com
Subject: Re: [RFC PATCH v2 55/58] drivers/iommu: Add deferred map_sg
 operations

On Thu, Dec 19, 2024 at 02:24:05PM +0000, Mostafa Saleh wrote:
> I had a quick look now at s390, and it seems a bit different as they only
> notify the hypervisor about the iova range being changed, and don’t need
> to provide iova->paddr mapping which pKVM does.

Can you explain this statement some more. It seems strange to me, why
would the pkvm side, which has it's own page table, need to be be told
about the iova->paddr during range unmapping requests - and why would
the host/guest side have to unnecessarily store this information?

Jason