Linux IOMMU Development
 help / color / mirror / Atom feed
From: Lu Baolu <baolu.lu@linux.intel.com>
To: Yi Liu <yi.l.liu@intel.com>, "Tian, Kevin" <kevin.tian@intel.com>,
	Joerg Roedel <joro@8bytes.org>, Jason Gunthorpe <jgg@nvidia.com>,
	Christoph Hellwig <hch@infradead.org>,
	"Raj, Ashok" <ashok.raj@intel.com>, Will Deacon <will@kernel.org>,
	Robin Murphy <robin.murphy@arm.com>,
	Jean-Philippe Brucker <jean-philippe@linaro.com>
Cc: "iommu@lists.linux-foundation.org"
	<iommu@lists.linux-foundation.org>,
	"Pan, Jacob jun" <jacob.jun.pan@intel.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH RFC v3 02/12] iommu: Add a flag to indicate immutable singleton group
Date: Tue, 12 Apr 2022 19:56:14 +0800	[thread overview]
Message-ID: <317c1d39-13df-2559-dff7-2a5c82630739@linux.intel.com> (raw)
In-Reply-To: <e8d8d08c-8327-b0ad-6bdd-ef10cd34e212@intel.com>

Hi Yi,

On 2022/4/12 14:34, Yi Liu wrote:
>>>
>>>>
>>>> This adds a flag in the iommu_group struct to indicate an immutable
>>>> singleton group, and uses standard PCI bus topology, isolation 
>>>> features,
>>>> and DMA alias quirks to set the flag. If the device came from DT, 
>>>> assume
>>>> it is static and then the singleton attribute can know from the device
>>>> count in the group.
>>>
>>> where does the assumption come from?
>>
>> Hotplug is the only factor that can dynamically affect the
>> characteristics of IOMMU group singleton as far as I can see. If a
>> device node was created from the DT, it could be treated as static,
>> hence we can judge the singleton in iommu probe phase during boot.
> 
> not sure if hotplug is the only factor. Is it possible that admin modifies
> the ACS configuration on the bridge?

Not likely. This will completely change the existing iommu_group
settings.

Best regards,
baolu
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

  reply	other threads:[~2022-04-12 11:56 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-10 10:24 [PATCH RFC v3 00/12] iommu: SVA and IOPF refactoring Lu Baolu
2022-04-10 10:24 ` [PATCH RFC v3 01/12] iommu: Add pasid_bits field in struct dev_iommu Lu Baolu
2022-04-10 10:24 ` [PATCH RFC v3 02/12] iommu: Add a flag to indicate immutable singleton group Lu Baolu
2022-04-12  3:15   ` Tian, Kevin
2022-04-12  5:08     ` Lu Baolu
2022-04-12  6:34       ` Yi Liu
2022-04-12 11:56         ` Lu Baolu [this message]
2022-04-12  7:37       ` Tian, Kevin
2022-04-12 13:02         ` Lu Baolu
2022-04-12 23:32           ` Tian, Kevin
2022-04-13 12:02             ` Lu Baolu
2022-04-12  7:39   ` Tian, Kevin
2022-04-12 13:10     ` Lu Baolu
2022-04-10 10:24 ` [PATCH RFC v3 03/12] iommu: Add attach/detach_dev_pasid domain ops Lu Baolu
2022-04-10 10:24 ` [PATCH RFC v3 04/12] iommu/sva: Basic data structures for SVA Lu Baolu
2022-04-12  6:49   ` Tian, Kevin
2022-04-12 11:58     ` Lu Baolu
2022-04-12  6:56   ` Tian, Kevin
2022-04-12 12:08     ` Lu Baolu
2022-04-10 10:24 ` [PATCH RFC v3 05/12] iommu/vt-d: Remove SVM_FLAG_SUPERVISOR_MODE support Lu Baolu
2022-04-10 10:24 ` [PATCH RFC v3 06/12] iommu/vt-d: Add SVA domain support Lu Baolu
2022-04-10 10:24 ` [PATCH RFC v3 07/12] arm-smmu-v3/sva: " Lu Baolu
2022-04-10 10:24 ` [PATCH RFC v3 08/12] iommu/sva: Use attach/detach_pasid_dev in SVA interfaces Lu Baolu
2022-04-12  7:19   ` Tian, Kevin
2022-04-12 12:53     ` Lu Baolu
2022-04-12 23:36       ` Tian, Kevin
2022-04-13 11:57         ` Lu Baolu
2022-04-14  3:44           ` Tian, Kevin
2022-04-10 10:24 ` [PATCH RFC v3 09/12] iommu: Remove SVA related callbacks from iommu ops Lu Baolu
2022-04-10 10:24 ` [PATCH RFC v3 10/12] iommu: Prepare IOMMU domain for IOPF Lu Baolu
2022-04-10 10:24 ` [PATCH RFC v3 11/12] iommu: Per-domain I/O page fault handling Lu Baolu
2022-04-10 10:24 ` [PATCH RFC v3 12/12] iommu: Rename iommu-sva-lib.{c,h} Lu Baolu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=317c1d39-13df-2559-dff7-2a5c82630739@linux.intel.com \
    --to=baolu.lu@linux.intel.com \
    --cc=ashok.raj@intel.com \
    --cc=hch@infradead.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=jacob.jun.pan@intel.com \
    --cc=jean-philippe@linaro.com \
    --cc=jgg@nvidia.com \
    --cc=joro@8bytes.org \
    --cc=kevin.tian@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=robin.murphy@arm.com \
    --cc=will@kernel.org \
    --cc=yi.l.liu@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox