From: Christoph Hellwig <hch@lst.de>
To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: "Christoph Hellwig" <hch@lst.de>,
"Dan Williams" <dan.j.williams@intel.com>,
"Bharata B Rao" <bharata@linux.ibm.com>,
"Christian König" <christian.koenig@amd.com>,
"Ben Skeggs" <bskeggs@redhat.com>,
"Jerome Glisse" <jglisse@redhat.com>,
kvm-ppc@vger.kernel.org, amd-gfx@lists.freedesktop.org,
dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
linux-mm@kvack.org
Subject: Re: [PATCH 1/2] mm: handle multiple owners of device private pages in migrate_vma
Date: Mon, 16 Mar 2020 19:20:39 +0100 [thread overview]
Message-ID: <20200316182039.GA24736@lst.de> (raw)
In-Reply-To: <20200316181707.GJ20941@ziepe.ca>
On Mon, Mar 16, 2020 at 03:17:07PM -0300, Jason Gunthorpe wrote:
> On Mon, Mar 16, 2020 at 06:52:58PM +0100, Christoph Hellwig wrote:
> > Add a new opaque owner field to struct dev_pagemap, which will allow
> > the hmm and migrate_vma code to identify who owns ZONE_DEVICE memory,
> > and refuse to work on mappings not owned by the calling entity.
>
> Using a pointer seems like a good solution to me.
>
> Is this a bug fix? What is the downside for migrate on pages it
> doesn't work? I'm not up to speed on migrate..
migrating private pages not owned by driver simply won't work, as
the device can't access it. Even inside the same driver say
GPU A can't just migrate CPU B's memory. In that sense it is
a bug fix for the rather unlikely case of using the experimental
nouveau with multiple GPUs, or in a power secure VM (if that is
even possible).
WARNING: multiple messages have this Message-ID (diff)
From: Christoph Hellwig <hch@lst.de>
To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: amd-gfx@lists.freedesktop.org, nouveau@lists.freedesktop.org,
dri-devel@lists.freedesktop.org, kvm-ppc@vger.kernel.org,
"Christoph Hellwig" <hch@lst.de>,
linux-mm@kvack.org, "Jerome Glisse" <jglisse@redhat.com>,
"Ben Skeggs" <bskeggs@redhat.com>,
"Dan Williams" <dan.j.williams@intel.com>,
"Bharata B Rao" <bharata@linux.ibm.com>,
"Christian König" <christian.koenig@amd.com>
Subject: Re: [PATCH 1/2] mm: handle multiple owners of device private pages in migrate_vma
Date: Mon, 16 Mar 2020 19:20:39 +0100 [thread overview]
Message-ID: <20200316182039.GA24736@lst.de> (raw)
In-Reply-To: <20200316181707.GJ20941@ziepe.ca>
On Mon, Mar 16, 2020 at 03:17:07PM -0300, Jason Gunthorpe wrote:
> On Mon, Mar 16, 2020 at 06:52:58PM +0100, Christoph Hellwig wrote:
> > Add a new opaque owner field to struct dev_pagemap, which will allow
> > the hmm and migrate_vma code to identify who owns ZONE_DEVICE memory,
> > and refuse to work on mappings not owned by the calling entity.
>
> Using a pointer seems like a good solution to me.
>
> Is this a bug fix? What is the downside for migrate on pages it
> doesn't work? I'm not up to speed on migrate..
migrating private pages not owned by driver simply won't work, as
the device can't access it. Even inside the same driver say
GPU A can't just migrate CPU B's memory. In that sense it is
a bug fix for the rather unlikely case of using the experimental
nouveau with multiple GPUs, or in a power secure VM (if that is
even possible).
_______________________________________________
amd-gfx mailing list
amd-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/amd-gfx
WARNING: multiple messages have this Message-ID (diff)
From: Christoph Hellwig <hch@lst.de>
To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: "Christoph Hellwig" <hch@lst.de>,
"Dan Williams" <dan.j.williams@intel.com>,
"Bharata B Rao" <bharata@linux.ibm.com>,
"Christian König" <christian.koenig@amd.com>,
"Ben Skeggs" <bskeggs@redhat.com>,
"Jerome Glisse" <jglisse@redhat.com>,
kvm-ppc@vger.kernel.org, amd-gfx@lists.freedesktop.org,
dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
linux-mm@kvack.org
Subject: Re: [PATCH 1/2] mm: handle multiple owners of device private pages in migrate_vma
Date: Mon, 16 Mar 2020 18:20:39 +0000 [thread overview]
Message-ID: <20200316182039.GA24736@lst.de> (raw)
In-Reply-To: <20200316181707.GJ20941@ziepe.ca>
On Mon, Mar 16, 2020 at 03:17:07PM -0300, Jason Gunthorpe wrote:
> On Mon, Mar 16, 2020 at 06:52:58PM +0100, Christoph Hellwig wrote:
> > Add a new opaque owner field to struct dev_pagemap, which will allow
> > the hmm and migrate_vma code to identify who owns ZONE_DEVICE memory,
> > and refuse to work on mappings not owned by the calling entity.
>
> Using a pointer seems like a good solution to me.
>
> Is this a bug fix? What is the downside for migrate on pages it
> doesn't work? I'm not up to speed on migrate..
migrating private pages not owned by driver simply won't work, as
the device can't access it. Even inside the same driver say
GPU A can't just migrate CPU B's memory. In that sense it is
a bug fix for the rather unlikely case of using the experimental
nouveau with multiple GPUs, or in a power secure VM (if that is
even possible).
next prev parent reply other threads:[~2020-03-16 18:20 UTC|newest]
Thread overview: 196+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-16 17:52 ensure device private pages have an owner Christoph Hellwig
2020-03-16 17:52 ` Christoph Hellwig
2020-03-16 17:52 ` Christoph Hellwig
2020-03-16 17:52 ` [PATCH 1/2] mm: handle multiple owners of device private pages in migrate_vma Christoph Hellwig
2020-03-16 17:52 ` Christoph Hellwig
2020-03-16 17:52 ` Christoph Hellwig
2020-03-16 18:17 ` Jason Gunthorpe
2020-03-16 18:17 ` Jason Gunthorpe
2020-03-16 18:17 ` Jason Gunthorpe
2020-03-16 18:17 ` Jason Gunthorpe
2020-03-16 18:20 ` Christoph Hellwig [this message]
2020-03-16 18:20 ` Christoph Hellwig
2020-03-16 18:20 ` Christoph Hellwig
2020-03-16 17:52 ` [PATCH 2/2] mm: remove device private page support from hmm_range_fault Christoph Hellwig
2020-03-16 17:52 ` Christoph Hellwig
2020-03-16 17:52 ` Christoph Hellwig
2020-03-16 18:42 ` Ralph Campbell
2020-03-16 18:42 ` Ralph Campbell
2020-03-16 18:42 ` Ralph Campbell
2020-03-16 18:42 ` Ralph Campbell
2020-03-16 18:42 ` Ralph Campbell
2020-03-16 18:49 ` Christoph Hellwig
2020-03-16 18:49 ` Christoph Hellwig
2020-03-16 18:49 ` Christoph Hellwig
2020-03-16 18:58 ` Christoph Hellwig
2020-03-16 18:58 ` Christoph Hellwig
2020-03-16 18:58 ` Christoph Hellwig
2020-03-16 19:56 ` Ralph Campbell
2020-03-16 19:56 ` Ralph Campbell
2020-03-16 19:56 ` Ralph Campbell
2020-03-16 19:56 ` Ralph Campbell
2020-03-16 20:09 ` Jason Gunthorpe
2020-03-16 20:09 ` Jason Gunthorpe
2020-03-16 20:09 ` Jason Gunthorpe
2020-03-16 20:09 ` Jason Gunthorpe
2020-03-16 20:24 ` Ralph Campbell
2020-03-16 20:24 ` Ralph Campbell
2020-03-16 20:24 ` Ralph Campbell
2020-03-16 20:24 ` Ralph Campbell
2020-03-17 11:56 ` Jason Gunthorpe
2020-03-17 11:56 ` Jason Gunthorpe
2020-03-17 11:56 ` Jason Gunthorpe
2020-03-17 11:56 ` Jason Gunthorpe
2020-03-17 22:46 ` Ralph Campbell
2020-03-17 22:46 ` Ralph Campbell
2020-03-17 22:46 ` Ralph Campbell
2020-03-17 22:46 ` Ralph Campbell
2020-03-16 19:04 ` Jason Gunthorpe
2020-03-16 19:04 ` Jason Gunthorpe
2020-03-16 19:04 ` Jason Gunthorpe
2020-03-16 19:04 ` Jason Gunthorpe
2020-03-16 19:07 ` Christoph Hellwig
2020-03-16 19:07 ` Christoph Hellwig
2020-03-16 19:07 ` Christoph Hellwig
2020-03-16 19:32 ensure device private pages have an owner v2 Christoph Hellwig
2020-03-16 19:32 ` Christoph Hellwig
2020-03-16 19:32 ` Christoph Hellwig
2020-03-16 19:32 ` [PATCH 1/4] memremap: add an owner field to struct dev_pagemap Christoph Hellwig
2020-03-16 19:32 ` Christoph Hellwig
2020-03-16 19:32 ` Christoph Hellwig
2020-03-16 20:55 ` Ralph Campbell
2020-03-16 20:55 ` Ralph Campbell
2020-03-16 20:55 ` Ralph Campbell
2020-03-16 20:55 ` Ralph Campbell
2020-03-16 20:55 ` Ralph Campbell
2020-03-16 19:32 ` [PATCH 2/4] mm: handle multiple owners of device private pages in migrate_vma Christoph Hellwig
2020-03-16 19:32 ` Christoph Hellwig
2020-03-16 19:32 ` Christoph Hellwig
2020-03-16 21:43 ` Ralph Campbell
2020-03-16 21:43 ` Ralph Campbell
2020-03-16 21:43 ` Ralph Campbell
2020-03-16 21:43 ` Ralph Campbell
2020-03-16 21:43 ` Ralph Campbell
2020-03-16 19:32 ` [PATCH 3/4] mm: simplify device private page handling in hmm_range_fault Christoph Hellwig
2020-03-16 19:32 ` Christoph Hellwig
2020-03-16 19:32 ` Christoph Hellwig
2020-03-16 19:59 ` Jason Gunthorpe
2020-03-16 19:59 ` Jason Gunthorpe
2020-03-16 19:59 ` Jason Gunthorpe
2020-03-16 19:59 ` Jason Gunthorpe
2020-03-16 21:33 ` Christoph Hellwig
2020-03-16 21:33 ` Christoph Hellwig
2020-03-16 21:33 ` Christoph Hellwig
2020-03-16 22:49 ` Ralph Campbell
2020-03-16 22:49 ` Ralph Campbell
2020-03-16 22:49 ` Ralph Campbell
2020-03-16 22:49 ` Ralph Campbell
2020-03-16 22:49 ` Ralph Campbell
2020-03-17 7:34 ` Christoph Hellwig
2020-03-17 7:34 ` Christoph Hellwig
2020-03-17 7:34 ` Christoph Hellwig
2020-03-17 22:43 ` Ralph Campbell
2020-03-17 22:43 ` Ralph Campbell
2020-03-17 22:43 ` Ralph Campbell
2020-03-17 22:43 ` Ralph Campbell
2020-03-18 9:34 ` Christoph Hellwig
2020-03-18 9:34 ` Christoph Hellwig
2020-03-18 9:34 ` Christoph Hellwig
2020-03-17 12:15 ` Jason Gunthorpe
2020-03-17 12:15 ` Jason Gunthorpe
2020-03-17 12:15 ` Jason Gunthorpe
2020-03-17 12:15 ` Jason Gunthorpe
2020-03-17 12:24 ` Christoph Hellwig
2020-03-17 12:24 ` Christoph Hellwig
2020-03-17 12:24 ` Christoph Hellwig
2020-03-17 12:28 ` Christoph Hellwig
2020-03-17 12:28 ` Christoph Hellwig
2020-03-17 12:28 ` Christoph Hellwig
2020-03-17 12:47 ` Jason Gunthorpe
2020-03-17 12:47 ` Jason Gunthorpe
2020-03-17 12:47 ` Jason Gunthorpe
2020-03-17 12:47 ` Jason Gunthorpe
2020-03-17 12:59 ` Christoph Hellwig
2020-03-17 12:59 ` Christoph Hellwig
2020-03-17 12:59 ` Christoph Hellwig
2020-03-17 17:32 ` Jason Gunthorpe
2020-03-17 17:32 ` Jason Gunthorpe
2020-03-17 17:32 ` Jason Gunthorpe
2020-03-17 17:32 ` Jason Gunthorpe
2020-03-17 17:32 ` Jason Gunthorpe
2020-03-17 23:14 ` Ralph Campbell
2020-03-17 23:14 ` Ralph Campbell
2020-03-17 23:14 ` Ralph Campbell
2020-03-17 23:14 ` Ralph Campbell
2020-03-19 18:17 ` Jason Gunthorpe
2020-03-19 18:17 ` Jason Gunthorpe
2020-03-19 18:17 ` Jason Gunthorpe
2020-03-19 18:17 ` Jason Gunthorpe
2020-03-19 22:56 ` Ralph Campbell
2020-03-19 22:56 ` Ralph Campbell
2020-03-19 22:56 ` Ralph Campbell
2020-03-19 22:56 ` Ralph Campbell
2020-03-20 0:03 ` Jason Gunthorpe
2020-03-20 0:03 ` Jason Gunthorpe
2020-03-20 0:03 ` Jason Gunthorpe
2020-03-20 0:03 ` Jason Gunthorpe
2020-03-21 8:20 ` Christoph Hellwig
2020-03-21 8:20 ` Christoph Hellwig
2020-03-21 8:20 ` Christoph Hellwig
2020-03-20 0:14 ` Jason Gunthorpe
2020-03-20 0:14 ` Jason Gunthorpe
2020-03-20 0:14 ` Jason Gunthorpe
2020-03-20 0:14 ` Jason Gunthorpe
2020-03-20 1:33 ` Ralph Campbell
2020-03-20 1:33 ` Ralph Campbell
2020-03-20 1:33 ` Ralph Campbell
2020-03-20 1:33 ` Ralph Campbell
2020-03-20 12:58 ` Jason Gunthorpe
2020-03-20 12:58 ` Jason Gunthorpe
2020-03-20 12:58 ` Jason Gunthorpe
2020-03-20 12:58 ` Jason Gunthorpe
2020-03-20 12:58 ` Jason Gunthorpe
2020-03-16 19:32 ` [PATCH 4/4] mm: check the device private page owner " Christoph Hellwig
2020-03-16 19:32 ` Christoph Hellwig
2020-03-16 19:32 ` Christoph Hellwig
2020-03-16 19:49 ` Jason Gunthorpe
2020-03-16 19:49 ` Jason Gunthorpe
2020-03-16 19:49 ` Jason Gunthorpe
2020-03-16 19:49 ` Jason Gunthorpe
2020-03-16 23:11 ` Ralph Campbell
2020-03-16 23:11 ` Ralph Campbell
2020-03-16 23:11 ` Ralph Campbell
2020-03-16 23:11 ` Ralph Campbell
2020-03-16 23:11 ` Ralph Campbell
2020-03-20 13:41 ` Jason Gunthorpe
2020-03-20 13:41 ` Jason Gunthorpe
2020-03-20 13:41 ` Jason Gunthorpe
2020-03-20 13:41 ` Jason Gunthorpe
2020-03-21 8:22 ` Christoph Hellwig
2020-03-21 8:22 ` Christoph Hellwig
2020-03-21 8:22 ` Christoph Hellwig
2020-03-21 12:38 ` Jason Gunthorpe
2020-03-21 12:38 ` Jason Gunthorpe
2020-03-21 12:38 ` Jason Gunthorpe
2020-03-21 12:38 ` Jason Gunthorpe
2020-03-21 15:18 ` Christoph Hellwig
2020-03-21 15:18 ` Christoph Hellwig
2020-03-21 15:18 ` Christoph Hellwig
2020-03-17 5:31 ` ensure device private pages have an owner v2 Bharata B Rao
2020-03-17 5:43 ` Bharata B Rao
2020-03-17 5:31 ` Bharata B Rao
2020-03-19 0:28 ` Jason Gunthorpe
2020-03-19 0:28 ` Jason Gunthorpe
2020-03-19 0:28 ` Jason Gunthorpe
2020-03-19 0:28 ` Jason Gunthorpe
2020-03-19 7:16 ` Christoph Hellwig
2020-03-19 7:16 ` Christoph Hellwig
2020-03-19 7:16 ` Christoph Hellwig
2020-03-19 11:50 ` Jason Gunthorpe
2020-03-19 11:50 ` Jason Gunthorpe
2020-03-19 11:50 ` Jason Gunthorpe
2020-03-19 11:50 ` Jason Gunthorpe
2020-03-19 18:50 ` Jason Gunthorpe
2020-03-19 18:50 ` Jason Gunthorpe
2020-03-19 18:50 ` Jason Gunthorpe
2020-03-19 18:50 ` Jason Gunthorpe
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