From: Christoph Hellwig <hch@lst.de>
To: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Christoph Hellwig <hch@lst.de>,
Christoph Hellwig <hch@infradead.org>,
linux-kernel@vger.kernel.org
Subject: Re: ehci-pci breakage with dma-mapping changes in 5.4-rc2
Date: Tue, 8 Oct 2019 14:50:08 +0200 [thread overview]
Message-ID: <20191008125008.GA4829@lst.de> (raw)
In-Reply-To: <20191008115103.GA463127@rani.riverdale.lan>
On Tue, Oct 08, 2019 at 07:51:03AM -0400, Arvind Sankar wrote:
> What I mean is, do there exist devices (which would necessarily support
> 64-bit DMA) that want to DMA using bigger than 4Gb buffers. Eg a GPU
> accelerator card with 16Gb of RAM on-board that wants to map 6Gb for DMA
> in one go, or 5 accelerator cards that are in one IOMMU domain and want
> to simultaneously map 1Gb each.
If you allocate more than 32-bits worth of address space the IOMMU
address space allocator will dip into 64-bit values if the device
dma mask supports that.
next prev parent reply other threads:[~2019-10-08 12:50 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-07 2:24 ehci-pci breakage with dma-mapping changes in 5.4-rc2 Arvind Sankar
2019-10-07 7:34 ` Christoph Hellwig
2019-10-07 17:54 ` Arvind Sankar
2019-10-07 17:55 ` Christoph Hellwig
2019-10-07 17:56 ` Christoph Hellwig
2019-10-07 17:58 ` Arvind Sankar
2019-10-07 18:32 ` Arvind Sankar
2019-10-07 18:47 ` Christoph Hellwig
2019-10-07 22:10 ` Arvind Sankar
2019-10-07 23:54 ` Arvind Sankar
2019-10-08 7:32 ` Christoph Hellwig
2019-10-08 11:51 ` Arvind Sankar
2019-10-08 12:50 ` Christoph Hellwig [this message]
2019-10-08 15:47 ` Arvind Sankar
2019-10-09 6:50 ` Christoph Hellwig
2019-10-09 13:48 ` Arvind Sankar
2019-10-08 7:29 ` Christoph Hellwig
2019-10-08 14:33 ` [PATCH] iommu/vt-d: Return the correct dma mask when we are bypassing the IOMMU Arvind Sankar
2019-10-09 2:45 ` Lu Baolu
2019-10-09 6:51 ` Christoph Hellwig
2019-10-10 1:24 ` Lu Baolu
2019-10-10 1:26 ` Lu Baolu
2019-10-16 19:15 ` Arvind Sankar
2019-10-17 7:08 ` Christoph Hellwig
2019-10-17 15:55 ` Arvind Sankar
2019-10-17 15:55 ` Arvind Sankar
2019-10-18 9:50 ` Joerg Roedel
2019-10-18 15:14 ` Christoph Hellwig
2019-10-18 15:21 ` Joerg Roedel
2019-10-18 15:22 ` Christoph Hellwig
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=20191008125008.GA4829@lst.de \
--to=hch@lst.de \
--cc=hch@infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=nivedita@alum.mit.edu \
/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.