From: Benjamin Herrenschmidt <benh@au1.ibm.com>
To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: "Dan Williams" <dan.j.williams@intel.com>,
"Logan Gunthorpe" <logang@deltatee.com>,
"Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>,
linux-pci@vger.kernel.org, linux-nvme@lists.infradead.org,
linux-rdma <linux-rdma@vger.kernel.org>,
linux-nvdimm <linux-nvdimm@lists.01.org>,
linux-block@vger.kernel.org,
"Stephen Bates" <sbates@raithlin.com>,
"Christoph Hellwig" <hch@lst.de>, "Jens Axboe" <axboe@kernel.dk>,
"Keith Busch" <keith.busch@intel.com>,
"Sagi Grimberg" <sagi@grimberg.me>,
"Bjorn Helgaas" <bhelgaas@google.com>,
"Max Gurtovoy" <maxg@mellanox.com>,
"Jérôme Glisse" <jglisse@redhat.com>,
"Alex Williamson" <alex.williamson@redhat.com>,
"Oliver OHalloran" <oliveroh@au1.ibm.com>
Subject: Re: [PATCH v2 00/10] Copy Offload in NVMe Fabrics with P2P PCI Memory
Date: Fri, 02 Mar 2018 09:06:52 +1100 [thread overview]
Message-ID: <1519942012.4592.31.camel@au1.ibm.com> (raw)
In-Reply-To: <20180301205315.GJ19007@ziepe.ca>
On Thu, 2018-03-01 at 13:53 -0700, Jason Gunthorpe wrote:
> On Fri, Mar 02, 2018 at 07:40:15AM +1100, Benjamin Herrenschmidt wrote:
> > Also we need to be able to hard block MEMREMAP_WB mappings of non-RAM
> > on ppc64 (maybe via an arch hook as it might depend on the processor
> > family). Server powerpc cannot do cachable accesses on IO memory
> > (unless it's special OpenCAPI or nVlink, but not on PCIe).
>
> I think you are right on this - even on x86 we must not create
> cachable mappings of PCI BARs - there is no way that works the way
> anyone would expect.
>
> I think this series doesn't have a problem here only because it never
> touches the BAR pages with the CPU.
>
> BAR memory should be mapped into the CPU as WC at best on all arches..
Could be that x86 has the smarts to do the right thing, still trying to
untangle the code :-)
Cheers,
Ben.
next prev parent reply other threads:[~2018-03-01 22:07 UTC|newest]
Thread overview: 124+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-28 23:39 [PATCH v2 00/10] Copy Offload in NVMe Fabrics with P2P PCI Memory Logan Gunthorpe
2018-02-28 23:39 ` [PATCH v2 01/10] PCI/P2PDMA: Support peer to peer memory Logan Gunthorpe
2018-03-01 17:37 ` Bjorn Helgaas
2018-03-01 18:55 ` Logan Gunthorpe
2018-03-01 23:00 ` Bjorn Helgaas
2018-03-01 23:06 ` Logan Gunthorpe
2018-03-01 23:14 ` Stephen Bates
2018-03-01 23:45 ` Bjorn Helgaas
2018-02-28 23:39 ` [PATCH v2 02/10] PCI/P2PDMA: Add sysfs group to display p2pmem stats Logan Gunthorpe
2018-03-01 17:44 ` Bjorn Helgaas
2018-03-02 0:15 ` Logan Gunthorpe
2018-03-02 0:36 ` Dan Williams
2018-03-02 0:37 ` Logan Gunthorpe
2018-02-28 23:39 ` [PATCH v2 03/10] PCI/P2PDMA: Add PCI p2pmem dma mappings to adjust the bus offset Logan Gunthorpe
2018-03-01 17:49 ` Bjorn Helgaas
2018-03-01 19:36 ` Logan Gunthorpe
2018-02-28 23:40 ` [PATCH v2 04/10] PCI/P2PDMA: Clear ACS P2P flags for all devices behind switches Logan Gunthorpe
2018-03-01 18:02 ` Bjorn Helgaas
2018-03-01 18:54 ` Stephen Bates
2018-03-01 21:21 ` Alex Williamson
2018-03-01 21:26 ` Logan Gunthorpe
2018-03-01 21:32 ` Stephen Bates
2018-03-01 21:35 ` Jerome Glisse
2018-03-01 21:37 ` Logan Gunthorpe
2018-03-01 23:15 ` Bjorn Helgaas
2018-03-01 23:59 ` Logan Gunthorpe
2018-03-01 19:13 ` Logan Gunthorpe
2018-03-05 22:28 ` Bjorn Helgaas
2018-03-05 23:01 ` Logan Gunthorpe
2018-02-28 23:40 ` [PATCH v2 05/10] block: Introduce PCI P2P flags for request and request queue Logan Gunthorpe
2018-03-01 11:08 ` Sagi Grimberg
2018-02-28 23:40 ` [PATCH v2 06/10] IB/core: Add optional PCI P2P flag to rdma_rw_ctx_[init|destroy]() Logan Gunthorpe
2018-03-01 10:32 ` Sagi Grimberg
2018-03-01 17:16 ` Logan Gunthorpe
2018-02-28 23:40 ` [PATCH v2 07/10] nvme-pci: Use PCI p2pmem subsystem to manage the CMB Logan Gunthorpe
2018-03-05 1:33 ` Oliver
2018-03-05 16:00 ` Keith Busch
2018-03-05 17:10 ` Logan Gunthorpe
2018-03-05 18:02 ` Sinan Kaya
2018-03-05 18:09 ` Logan Gunthorpe
2018-03-06 0:49 ` Oliver
2018-03-06 1:14 ` Logan Gunthorpe
2018-03-06 10:40 ` Oliver
2018-03-05 19:57 ` Sagi Grimberg
2018-03-05 20:10 ` Jason Gunthorpe
2018-03-05 20:16 ` Logan Gunthorpe
2018-03-05 20:42 ` Keith Busch
2018-03-05 20:50 ` Jason Gunthorpe
2018-03-05 20:13 ` Logan Gunthorpe
2018-02-28 23:40 ` [PATCH v2 08/10] nvme-pci: Add support for P2P memory in requests Logan Gunthorpe
2018-03-01 11:07 ` Sagi Grimberg
2018-03-01 15:58 ` Stephen Bates
2018-03-09 5:08 ` Bart Van Assche
2018-02-28 23:40 ` [PATCH v2 09/10] nvme-pci: Add a quirk for a pseudo CMB Logan Gunthorpe
2018-03-01 11:03 ` Sagi Grimberg
2018-02-28 23:40 ` [PATCH v2 10/10] nvmet: Optionally use PCI P2P memory Logan Gunthorpe
2018-03-01 11:03 ` Sagi Grimberg
2018-03-01 16:15 ` Stephen Bates
2018-03-01 17:40 ` Logan Gunthorpe
2018-03-01 18:35 ` Sagi Grimberg
2018-03-01 18:42 ` Jason Gunthorpe
2018-03-01 19:01 ` Stephen Bates
2018-03-01 19:27 ` Logan Gunthorpe
2018-03-01 22:45 ` Jason Gunthorpe
2018-03-01 22:56 ` Logan Gunthorpe
2018-03-01 23:00 ` Stephen Bates
2018-03-01 23:20 ` Jason Gunthorpe
2018-03-01 23:29 ` Logan Gunthorpe
2018-03-01 23:32 ` Stephen Bates
2018-03-01 23:49 ` Keith Busch
2018-03-01 23:52 ` Logan Gunthorpe
2018-03-01 23:53 ` Stephen Bates
2018-03-02 15:53 ` Christoph Hellwig
2018-03-02 20:51 ` Stephen Bates
2018-03-01 23:57 ` Stephen Bates
2018-03-02 0:03 ` Logan Gunthorpe
2018-03-02 16:18 ` Jason Gunthorpe
2018-03-02 17:10 ` Logan Gunthorpe
2018-03-01 19:10 ` Logan Gunthorpe
2018-03-01 3:54 ` [PATCH v2 00/10] Copy Offload in NVMe Fabrics with P2P PCI Memory Benjamin Herrenschmidt
2018-03-01 3:56 ` Benjamin Herrenschmidt
2018-03-01 18:04 ` Logan Gunthorpe
2018-03-01 20:29 ` Benjamin Herrenschmidt
2018-03-01 20:55 ` Jerome Glisse
2018-03-01 21:03 ` Logan Gunthorpe
2018-03-01 21:10 ` Jerome Glisse
2018-03-01 21:15 ` Logan Gunthorpe
2018-03-01 21:25 ` Jerome Glisse
2018-03-01 21:37 ` Stephen Bates
2018-03-02 21:38 ` Stephen Bates
2018-03-02 22:09 ` Jerome Glisse
2018-03-05 20:36 ` Stephen Bates
2018-03-01 20:55 ` Logan Gunthorpe
2018-03-01 18:09 ` Stephen Bates
2018-03-01 20:32 ` Benjamin Herrenschmidt
2018-03-01 19:21 ` Dan Williams
2018-03-01 19:30 ` Logan Gunthorpe
2018-03-01 20:34 ` Benjamin Herrenschmidt
2018-03-01 20:40 ` Benjamin Herrenschmidt
2018-03-01 20:53 ` Jason Gunthorpe
2018-03-01 20:57 ` Logan Gunthorpe
2018-03-01 22:06 ` Benjamin Herrenschmidt [this message]
2018-03-01 22:31 ` Linus Torvalds
2018-03-01 22:34 ` Benjamin Herrenschmidt
2018-03-02 16:22 ` Kani, Toshi
2018-03-02 16:57 ` Linus Torvalds
2018-03-02 17:34 ` Linus Torvalds
2018-03-02 17:38 ` Kani, Toshi
2018-03-01 21:37 ` Dan Williams
2018-03-01 21:45 ` Logan Gunthorpe
2018-03-01 21:57 ` Logan Gunthorpe
2018-03-01 23:00 ` Benjamin Herrenschmidt
2018-03-01 23:19 ` Logan Gunthorpe
2018-03-01 23:25 ` Benjamin Herrenschmidt
2018-03-02 21:44 ` Benjamin Herrenschmidt
2018-03-02 22:24 ` Logan Gunthorpe
2018-03-01 23:26 ` Benjamin Herrenschmidt
2018-03-01 23:54 ` Logan Gunthorpe
2018-03-01 21:03 ` Benjamin Herrenschmidt
2018-03-01 21:11 ` Logan Gunthorpe
2018-03-01 21:18 ` Jerome Glisse
2018-03-01 21:22 ` Logan Gunthorpe
2018-03-01 10:31 ` Sagi Grimberg
2018-03-01 19:33 ` Logan Gunthorpe
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=1519942012.4592.31.camel@au1.ibm.com \
--to=benh@au1.ibm.com \
--cc=alex.williamson@redhat.com \
--cc=axboe@kernel.dk \
--cc=bhelgaas@google.com \
--cc=dan.j.williams@intel.com \
--cc=hch@lst.de \
--cc=jgg@ziepe.ca \
--cc=jglisse@redhat.com \
--cc=keith.busch@intel.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvdimm@lists.01.org \
--cc=linux-nvme@lists.infradead.org \
--cc=linux-pci@vger.kernel.org \
--cc=linux-rdma@vger.kernel.org \
--cc=logang@deltatee.com \
--cc=maxg@mellanox.com \
--cc=oliveroh@au1.ibm.com \
--cc=sagi@grimberg.me \
--cc=sbates@raithlin.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;
as well as URLs for NNTP newsgroup(s).