linux-kernel - RE: [PATCH v2 08/22] iommufd: Abstract iopt_pin_pages and iopt_unpin

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: <BN9PR11MB52767C9253073156A63C27B98C88A@BN9PR11MB5276.namprd11.prod.outlook.com>
Date: Wed, 7 May 2025 07:51:11 +0000
From: "Tian, Kevin" <kevin.tian@...el.com>
To: Nicolin Chen <nicolinc@...dia.com>
CC: "jgg@...dia.com" <jgg@...dia.com>, "corbet@....net" <corbet@....net>,
	"will@...nel.org" <will@...nel.org>, "bagasdotme@...il.com"
	<bagasdotme@...il.com>, "robin.murphy@....com" <robin.murphy@....com>,
	"joro@...tes.org" <joro@...tes.org>, "thierry.reding@...il.com"
	<thierry.reding@...il.com>, "vdumpa@...dia.com" <vdumpa@...dia.com>,
	"jonathanh@...dia.com" <jonathanh@...dia.com>, "shuah@...nel.org"
	<shuah@...nel.org>, "jsnitsel@...hat.com" <jsnitsel@...hat.com>,
	"nathan@...nel.org" <nathan@...nel.org>, "peterz@...radead.org"
	<peterz@...radead.org>, "Liu, Yi L" <yi.l.liu@...el.com>,
	"mshavit@...gle.com" <mshavit@...gle.com>, "praan@...gle.com"
	<praan@...gle.com>, "zhangzekun11@...wei.com" <zhangzekun11@...wei.com>,
	"iommu@...ts.linux.dev" <iommu@...ts.linux.dev>, "linux-doc@...r.kernel.org"
	<linux-doc@...r.kernel.org>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>, "linux-arm-kernel@...ts.infradead.org"
	<linux-arm-kernel@...ts.infradead.org>, "linux-tegra@...r.kernel.org"
	<linux-tegra@...r.kernel.org>, "linux-kselftest@...r.kernel.org"
	<linux-kselftest@...r.kernel.org>, "patches@...ts.linux.dev"
	<patches@...ts.linux.dev>, "mochs@...dia.com" <mochs@...dia.com>,
	"alok.a.tiwari@...cle.com" <alok.a.tiwari@...cle.com>, "vasant.hegde@....com"
	<vasant.hegde@....com>
Subject: RE: [PATCH v2 08/22] iommufd: Abstract iopt_pin_pages and
 iopt_unpin_pages helpers

> From: Nicolin Chen <nicolinc@...dia.com>
> Sent: Wednesday, May 7, 2025 3:37 PM
> 
> On Wed, May 07, 2025 at 07:22:24AM +0000, Tian, Kevin wrote:
> > > > any reason why this cannot be done by the core? all types of vcmd
> > > > queues need to pin the guest buffer pages, no matter the IOMMU
> > > > accesses GPA or HPA.
> 
> > > But I am doing in the core. I have iopt_pin_pages() called in the
> > > core ioctl handler iommufd_vqueue_alloc_ioctl():
> 
> > IMHO we just want to keep the pin logic in the core while leaving
> > the check of PFN continuity to the driver (or have a way for the
> > driver to communicate such need to the core).
> >
> > It's possible for have an implementation with IOMMU accessing
> > GPA of the queue which further goes through the stage-2
> > translation. In such case it's fine to have disjointed PFNs.
> 
> That makes sense. In the iommufd_viommu_ops structure, we can add
> "u32 flag" where driver can define IOMMUFD_VQUEUE_CONTIGUOUS_PFNS?
> 

that works.