From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Jason Gunthorpe <jgg@nvidia.com>
Cc: Allen Hubbe <allenbh@gmail.com>,
linux-s390@vger.kernel.org, Kevin Tian <kevin.tian@intel.com>,
x86@kernel.org, Dave Jiang <dave.jiang@intel.com>,
Ashok Raj <ashok.raj@intel.com>, Marc Zygnier <maz@kernel.org>,
Heiko Carstens <hca@linux.ibm.com>,
LKML <linux-kernel@vger.kernel.org>,
iommu@lists.linux-foundation.org,
Christian Borntraeger <borntraeger@de.ibm.com>,
Alex Williamson <alex.williamson@redhat.com>,
Joerg Roedel <jroedel@suse.de>,
Bjorn Helgaas <helgaas@kernel.org>,
linux-pci@vger.kernel.org, linux-ntb@googlegroups.com,
Thomas Gleixner <tglx@linutronix.de>,
Logan Gunthorpe <logang@deltatee.com>,
Megha Dey <megha.dey@intel.com>
Subject: Re: [patch 21/32] NTB/msi: Convert to msi_on_each_desc()
Date: Thu, 2 Dec 2021 15:23:38 +0100 [thread overview]
Message-ID: <YajW6veanK4GZUkv@kroah.com> (raw)
In-Reply-To: <20211202135502.GP4670@nvidia.com>
On Thu, Dec 02, 2021 at 09:55:02AM -0400, Jason Gunthorpe wrote:
> Further, there is no reason why IMS should be reserved exclusively for
> VFIO! Why shouldn't the cdev be able to use IMS vectors too? It is
> just a feature of the PCI device like MSI. If the queue has a PASID it
> can use IDXD's IMS.
No, sorry, but a cdev is not for anything resembling any real resource
at all.
It is ONLY for the /dev/NODE interface that controls the character
device api to userspace. The struct device involved in it is ONLY for
that, nothing else. Any attempt to add things to it will be gleefully
rejected.
The cdev api today (in the kernel) exposes too much mess and there's at
least 4 or 5 different ways to use it. It's on my long-term TODO list
to fix this up to not even allow abuses like you are considering here,
so please don't do that.
> If we really need a 2nd struct device to turn on IMS then, I'd suggest
> picking the cdev, as it keeps IMS and its allocator inside the IDXD
> PCIe driver and not in the VFIO world.
No! Again, a cdev is to control the lifespan/lifecycle of the /dev/NODE
only. Anything other than that is not ok to do at all.
thanks,
greg k-h
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
next prev parent reply other threads:[~2021-12-02 14:23 UTC|newest]
Thread overview: 71+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20211126230957.239391799@linutronix.de>
[not found] ` <20211126232735.547996838@linutronix.de>
[not found] ` <7daba0e2-73a3-4980-c3a5-a71f6b597b22@deltatee.com>
[not found] ` <874k7ueldt.ffs@tglx>
[not found] ` <6ba084d6-2b26-7c86-4526-8fcd3d921dfd@deltatee.com>
[not found] ` <87ilwacwp8.ffs@tglx>
[not found] ` <d6f13729-1b83-fa7d-3f0d-98d4e3f7a2aa@deltatee.com>
[not found] ` <87v909bf2k.ffs@tglx>
[not found] ` <20211130202800.GE4670@nvidia.com>
[not found] ` <87o861banv.ffs@tglx>
[not found] ` <20211201001748.GF4670@nvidia.com>
2021-12-01 10:16 ` [patch 21/32] NTB/msi: Convert to msi_on_each_desc() Thomas Gleixner
2021-12-01 13:00 ` Jason Gunthorpe via iommu
2021-12-01 17:35 ` Thomas Gleixner
2021-12-01 18:14 ` Jason Gunthorpe via iommu
2021-12-01 18:46 ` Logan Gunthorpe
2021-12-01 20:21 ` Thomas Gleixner
2021-12-02 0:01 ` Thomas Gleixner
2021-12-02 13:55 ` Jason Gunthorpe via iommu
2021-12-02 14:23 ` Greg Kroah-Hartman [this message]
2021-12-02 14:45 ` Jason Gunthorpe via iommu
2021-12-02 19:25 ` Thomas Gleixner
2021-12-02 20:00 ` Jason Gunthorpe via iommu
2021-12-02 22:31 ` Thomas Gleixner
2021-12-03 0:37 ` Jason Gunthorpe via iommu
2021-12-03 15:07 ` Thomas Gleixner
2021-12-03 16:41 ` Jason Gunthorpe via iommu
2021-12-04 14:20 ` Thomas Gleixner
2021-12-05 14:16 ` Thomas Gleixner
2021-12-06 14:43 ` Jason Gunthorpe via iommu
2021-12-06 15:47 ` Thomas Gleixner
2021-12-06 17:00 ` Jason Gunthorpe via iommu
2021-12-06 20:28 ` Thomas Gleixner
2021-12-06 21:06 ` Jason Gunthorpe via iommu
2021-12-06 22:21 ` Thomas Gleixner
2021-12-06 14:19 ` Jason Gunthorpe via iommu
2021-12-06 15:06 ` Thomas Gleixner
2021-12-09 6:26 ` Tian, Kevin
2021-12-09 9:03 ` Thomas Gleixner
2021-12-09 12:17 ` Tian, Kevin
2021-12-09 15:57 ` Thomas Gleixner
2021-12-10 7:37 ` Tian, Kevin
2021-12-09 5:41 ` Tian, Kevin
2021-12-09 5:47 ` Jason Wang
2021-12-01 16:28 ` Dave Jiang
2021-12-01 18:41 ` Thomas Gleixner
2021-12-01 18:47 ` Dave Jiang
2021-12-01 20:25 ` Thomas Gleixner
2021-12-01 21:21 ` Dave Jiang
2021-12-01 21:44 ` Thomas Gleixner
2021-12-01 21:49 ` Dave Jiang
2021-12-01 22:03 ` Thomas Gleixner
2021-12-01 22:53 ` Dave Jiang
2021-12-01 23:57 ` Thomas Gleixner
2021-12-09 5:23 ` Tian, Kevin
2021-12-09 8:37 ` Thomas Gleixner
2021-12-09 12:31 ` Tian, Kevin
2021-12-09 16:21 ` Jason Gunthorpe via iommu
2021-12-09 20:32 ` Thomas Gleixner
2021-12-09 20:58 ` Jason Gunthorpe via iommu
2021-12-09 22:09 ` Thomas Gleixner
2021-12-10 0:26 ` Thomas Gleixner
2021-12-10 7:29 ` Tian, Kevin
2021-12-10 12:13 ` Thomas Gleixner
2021-12-11 8:06 ` Tian, Kevin
2021-12-10 12:39 ` Jason Gunthorpe via iommu
2021-12-10 19:00 ` Thomas Gleixner
2021-12-11 7:44 ` Tian, Kevin
2021-12-11 13:04 ` Thomas Gleixner
2021-12-12 1:56 ` Tian, Kevin
2021-12-12 20:55 ` Thomas Gleixner
2021-12-12 23:37 ` Jason Gunthorpe via iommu
2021-12-13 7:50 ` Tian, Kevin
2021-12-11 7:52 ` Tian, Kevin
2021-12-12 0:12 ` Thomas Gleixner
2021-12-12 2:14 ` Tian, Kevin
2021-12-12 20:50 ` Thomas Gleixner
2021-12-12 23:42 ` Jason Gunthorpe via iommu
2021-12-10 7:36 ` Tian, Kevin
2021-12-10 12:30 ` Jason Gunthorpe via iommu
2021-12-12 6:44 ` Mika Penttilä
2021-12-12 23:27 ` Jason Gunthorpe via iommu
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=YajW6veanK4GZUkv@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=alex.williamson@redhat.com \
--cc=allenbh@gmail.com \
--cc=ashok.raj@intel.com \
--cc=borntraeger@de.ibm.com \
--cc=dave.jiang@intel.com \
--cc=hca@linux.ibm.com \
--cc=helgaas@kernel.org \
--cc=iommu@lists.linux-foundation.org \
--cc=jgg@nvidia.com \
--cc=jroedel@suse.de \
--cc=kevin.tian@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-ntb@googlegroups.com \
--cc=linux-pci@vger.kernel.org \
--cc=linux-s390@vger.kernel.org \
--cc=logang@deltatee.com \
--cc=maz@kernel.org \
--cc=megha.dey@intel.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/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