xen-devel.lists.xenproject.org archive mirror
 help / color / mirror / Atom feed
From: Roland Dreier <rdreier@cisco.com>
To: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: jackm@mellanox.co.il, Jeremy Fitzhardinge <jeremy@goop.org>,
	xen-devel@lists.xensource.com, rdreir@cisco.com,
	linux-rdma@vger.kernel.org,
	Vivien Bernet-Rollande <vbr@soprive.net>,
	sean.hefty@intel.com
Subject: Re: Re: [PATCH] infiniband/mthca : Fix userland mapping of mthca infiniband cards in Xen dom0
Date: Thu, 06 Jan 2011 10:51:57 -0800	[thread overview]
Message-ID: <adalj2xdfw2.fsf@cisco.com> (raw)
In-Reply-To: <20110106165549.GC18774@dumpdata.com> (Konrad Rzeszutek Wilk's message of "Thu, 6 Jan 2011 11:55:49 -0500")

 > There is another way, which I hope can fix this issue (it fixes
 > the graphics drivers). Basically making the Xen MMU be aware of the E820
 > and consider any access to PFNs that are not in RAM to have VM_IO implicitly set.
 > 
 > The patches are at git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git
 > 
 > stable/p2m-identity.v4.3
 > 
 > And posted on LKML )https://lkml.org/lkml/2010/12/30/163)
 > 
 > They _should_ take care of your problem as long as the PFNs you
 > are mapping fall within the PCI BAR regions (which I would presume they
 > do since you are using ioremap).

Yes, that should work fine for all the cases I know of in the RDMA
drivers.  We are just mapping some PCI BAR space into userspace for
direct access to hardware (just like graphics, I think).

I definitely prefer a solution that doesn't require driver authors to
add a Xen-specific fix that isn't required on any other architecture.

 - R.

  reply	other threads:[~2011-01-06 18:51 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1293034260.30522.426.camel@trax>
2011-01-05 19:35 ` [PATCH] infiniband/mthca : Fix userland mapping of mthca infiniband cards in Xen dom0 Roland Dreier
     [not found]   ` <adamxnfdty8.fsf-FYB4Gu1CFyUAvxtiuMwx3w@public.gmane.org>
2011-01-06 11:08     ` Vivien Bernet-Rollande
2011-01-06 16:55       ` Konrad Rzeszutek Wilk
2011-01-06 18:51         ` Roland Dreier [this message]
     [not found]           ` <adalj2xdfw2.fsf-FYB4Gu1CFyUAvxtiuMwx3w@public.gmane.org>
2011-01-07 19:15             ` [Xen-devel] " Konrad Rzeszutek Wilk
     [not found]               ` <20110107191559.GA27871-Z2dCqgVfyhJWk0Htik3J/w@public.gmane.org>
2011-01-09  8:24                 ` Jack Morgenstein
     [not found]       ` <AANLkTi=zMiVJfTRDeYvbxT46b0iASKG9jPgXqG81bqAK-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2011-01-06 19:15         ` Roland Dreier

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=adalj2xdfw2.fsf@cisco.com \
    --to=rdreier@cisco.com \
    --cc=jackm@mellanox.co.il \
    --cc=jeremy@goop.org \
    --cc=konrad.wilk@oracle.com \
    --cc=linux-rdma@vger.kernel.org \
    --cc=rdreir@cisco.com \
    --cc=sean.hefty@intel.com \
    --cc=vbr@soprive.net \
    --cc=xen-devel@lists.xensource.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).