From: Jason Gunthorpe via iommu <iommu@lists.linux-foundation.org>
To: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: "Tian, Kevin" <kevin.tian@intel.com>,
Tony Luck <tony.luck@intel.com>,
Dave Jiang <dave.jiang@intel.com>,
Raj Ashok <ashok.raj@intel.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"Kumar, Sanjay K" <sanjay.k.kumar@intel.com>,
LKML <linux-kernel@vger.kernel.org>,
Christoph Hellwig <hch@infradead.org>,
iommu@lists.linux-foundation.org,
Jacob Pan <jacob.jun.pan@intel.com>,
Barry Song <21cnbao@gmail.com>,
Dan Williams <dan.j.williams@intel.com>,
Jean-Philippe Brucker <jean-philippe@linaro.com>,
"Zanussi, Tom" <tom.zanussi@intel.com>
Subject: Re: [PATCH 3/4] iommu/vt-d: Support PASID DMA for in-kernel usage
Date: Fri, 10 Dec 2021 14:53:40 -0400 [thread overview]
Message-ID: <20211210185340.GI6385@nvidia.com> (raw)
In-Reply-To: <20211210101820.58b24b77@jacob-builder>
On Fri, Dec 10, 2021 at 10:18:20AM -0800, Jacob Pan wrote:
> > If one device has 10 PASID's pointing to this domain you must flush
> > them all if that is what the HW requires.
> >
> Yes. My point is that other than PASID 0 is a given, we must track the 10
> PASIDs to avoid wasted flush. It also depend on how TLBs are tagged and
> flush granularity available. But at the API level, should we support all the
> cases?
Yes, iommufd will expose all the cases to userspace and anything is
possible.
A scheme that can only attach a domain to one PASID is functionally
useless except for this IDXD problem, so don't make something so
broken.
Jason
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
WARNING: multiple messages have this Message-ID (diff)
From: Jason Gunthorpe <jgg@nvidia.com>
To: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Lu Baolu <baolu.lu@linux.intel.com>,
iommu@lists.linux-foundation.org,
LKML <linux-kernel@vger.kernel.org>,
Joerg Roedel <joro@8bytes.org>,
Christoph Hellwig <hch@infradead.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jean-Philippe Brucker <jean-philippe@linaro.com>,
Jacob Pan <jacob.jun.pan@intel.com>,
Raj Ashok <ashok.raj@intel.com>,
"Kumar, Sanjay K" <sanjay.k.kumar@intel.com>,
Dave Jiang <dave.jiang@intel.com>,
Tony Luck <tony.luck@intel.com>, Yi Liu <yi.l.liu@intel.com>,
"Tian, Kevin" <kevin.tian@intel.com>,
Barry Song <21cnbao@gmail.com>,
"Zanussi, Tom" <tom.zanussi@intel.com>,
Dan Williams <dan.j.williams@intel.com>
Subject: Re: [PATCH 3/4] iommu/vt-d: Support PASID DMA for in-kernel usage
Date: Fri, 10 Dec 2021 14:53:40 -0400 [thread overview]
Message-ID: <20211210185340.GI6385@nvidia.com> (raw)
In-Reply-To: <20211210101820.58b24b77@jacob-builder>
On Fri, Dec 10, 2021 at 10:18:20AM -0800, Jacob Pan wrote:
> > If one device has 10 PASID's pointing to this domain you must flush
> > them all if that is what the HW requires.
> >
> Yes. My point is that other than PASID 0 is a given, we must track the 10
> PASIDs to avoid wasted flush. It also depend on how TLBs are tagged and
> flush granularity available. But at the API level, should we support all the
> cases?
Yes, iommufd will expose all the cases to userspace and anything is
possible.
A scheme that can only attach a domain to one PASID is functionally
useless except for this IDXD problem, so don't make something so
broken.
Jason
next prev parent reply other threads:[~2021-12-10 18:53 UTC|newest]
Thread overview: 93+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-07 13:47 [PATCH 0/4] Enable PASID for DMA API users Jacob Pan
2021-12-07 13:47 ` Jacob Pan
2021-12-07 13:47 ` [PATCH 1/4] ioasid: Reserve a global PASID for in-kernel DMA Jacob Pan
2021-12-07 13:47 ` Jacob Pan
2021-12-09 11:03 ` Jean-Philippe Brucker
2021-12-09 11:03 ` Jean-Philippe Brucker
2021-12-09 18:14 ` Jacob Pan
2021-12-09 18:14 ` Jacob Pan
2021-12-10 9:06 ` Jean-Philippe Brucker
2021-12-10 9:06 ` Jean-Philippe Brucker
2021-12-10 12:31 ` Jason Gunthorpe via iommu
2021-12-10 12:31 ` Jason Gunthorpe
2021-12-10 18:05 ` Jacob Pan
2021-12-10 18:05 ` Jacob Pan
2021-12-11 8:39 ` Tian, Kevin
2021-12-11 8:39 ` Tian, Kevin
2021-12-12 23:34 ` Jason Gunthorpe via iommu
2021-12-12 23:34 ` Jason Gunthorpe
2021-12-07 13:47 ` [PATCH 2/4] iommu: Add PASID support for DMA mapping API users Jacob Pan
2021-12-07 13:47 ` Jacob Pan
2021-12-08 2:31 ` Lu Baolu
2021-12-08 2:31 ` Lu Baolu
2021-12-08 18:49 ` Jacob Pan
2021-12-08 18:49 ` Jacob Pan
2021-12-09 1:56 ` Tian, Kevin
2021-12-09 1:56 ` Tian, Kevin
2021-12-09 2:21 ` Lu Baolu
2021-12-09 2:21 ` Lu Baolu
2021-12-09 16:32 ` Jacob Pan
2021-12-09 16:32 ` Jacob Pan
2021-12-09 16:57 ` Raj, Ashok
2021-12-09 16:57 ` Raj, Ashok
2021-12-09 17:34 ` Jacob Pan
2021-12-09 17:34 ` Jacob Pan
2021-12-07 13:47 ` [PATCH 3/4] iommu/vt-d: Support PASID DMA for in-kernel usage Jacob Pan
2021-12-07 13:47 ` Jacob Pan
2021-12-08 13:22 ` Jason Gunthorpe via iommu
2021-12-08 13:22 ` Jason Gunthorpe
2021-12-08 19:16 ` Jacob Pan
2021-12-08 19:16 ` Jacob Pan
2021-12-09 2:32 ` Lu Baolu
2021-12-09 2:32 ` Lu Baolu
2021-12-09 23:21 ` Jacob Pan
2021-12-09 23:21 ` Jacob Pan
2021-12-09 23:41 ` Jason Gunthorpe via iommu
2021-12-09 23:41 ` Jason Gunthorpe
2021-12-10 6:46 ` Lu Baolu
2021-12-10 6:46 ` Lu Baolu
2021-12-10 17:50 ` Jacob Pan
2021-12-10 17:50 ` Jacob Pan
2021-12-10 17:48 ` Jason Gunthorpe via iommu
2021-12-10 17:48 ` Jason Gunthorpe
2021-12-10 18:18 ` Jacob Pan
2021-12-10 18:18 ` Jacob Pan
2021-12-10 18:53 ` Jason Gunthorpe via iommu [this message]
2021-12-10 18:53 ` Jason Gunthorpe
2021-12-07 13:47 ` [PATCH 4/4] dmaengine: idxd: Use DMA API for in-kernel DMA with PASID Jacob Pan
2021-12-07 13:47 ` Jacob Pan
2021-12-07 23:27 ` Dave Jiang
2021-12-07 23:27 ` Dave Jiang
2021-12-08 4:56 ` Vinod Koul
2021-12-08 4:56 ` Vinod Koul
2021-12-08 17:36 ` Jacob Pan
2021-12-08 17:36 ` Jacob Pan
2021-12-08 13:13 ` Jason Gunthorpe via iommu
2021-12-08 13:13 ` Jason Gunthorpe
2021-12-08 15:35 ` Dave Jiang
2021-12-08 15:35 ` Dave Jiang
2021-12-08 17:51 ` Jason Gunthorpe via iommu
2021-12-08 17:51 ` Jason Gunthorpe
2021-12-09 1:48 ` Tian, Kevin
2021-12-09 1:48 ` Tian, Kevin
2021-12-09 19:18 ` Jacob Pan
2021-12-09 19:18 ` Jacob Pan
2021-12-08 19:55 ` Jacob Pan
2021-12-08 19:55 ` Jacob Pan
2021-12-08 20:30 ` Jason Gunthorpe via iommu
2021-12-08 20:30 ` Jason Gunthorpe
2021-12-08 21:59 ` Jacob Pan
2021-12-08 21:59 ` Jacob Pan
2021-12-08 23:39 ` Jason Gunthorpe via iommu
2021-12-08 23:39 ` Jason Gunthorpe
2021-12-09 0:12 ` Dave Jiang
2021-12-09 0:12 ` Dave Jiang
2021-12-09 2:06 ` Tian, Kevin
2021-12-09 2:06 ` Tian, Kevin
2021-12-08 18:37 ` kernel test robot
2021-12-08 18:37 ` kernel test robot
2021-12-08 18:37 ` kernel test robot
2021-12-08 13:10 ` [PATCH 0/4] Enable PASID for DMA API users Jason Gunthorpe via iommu
2021-12-08 13:10 ` Jason Gunthorpe
2021-12-08 18:15 ` Jacob Pan
2021-12-08 18:15 ` Jacob Pan
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=20211210185340.GI6385@nvidia.com \
--to=iommu@lists.linux-foundation.org \
--cc=21cnbao@gmail.com \
--cc=ashok.raj@intel.com \
--cc=dan.j.williams@intel.com \
--cc=dave.jiang@intel.com \
--cc=gregkh@linuxfoundation.org \
--cc=hch@infradead.org \
--cc=jacob.jun.pan@intel.com \
--cc=jacob.jun.pan@linux.intel.com \
--cc=jean-philippe@linaro.com \
--cc=jgg@nvidia.com \
--cc=kevin.tian@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=sanjay.k.kumar@intel.com \
--cc=tom.zanussi@intel.com \
--cc=tony.luck@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.