linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: John Rose <johnrose@austin.ibm.com>
To: Santiago Leon <saleon@us.ibm.com>,
	benh@kernel.crashing.org, External List <linuxppc-dev@ozlabs.org>
Subject: iommu hypervisor hypothetical
Date: Wed, 27 Sep 2006 11:47:51 -0500	[thread overview]
Message-ID: <1159375671.19103.3.camel@sinatra.austin.ibm.com> (raw)

Suppose the hypervisor added new failure codes for the hcall that does
tce_build().  Suppose that the device driver needed to expect such
failures when alloc_[coherent,consistent] is not successful, and handle
that case accordingly.

Is this something we can accommodate without rewriting the iommu stuff
for various platforms?  All these functions in machdep.h are defined to
return NULL.  Is this because we haven't had a reasonable expectation of
failure, or because device drivers _have_ to assume success for such
operations?

Thanks-
John

             reply	other threads:[~2006-09-27 16:50 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-09-27 16:47 John Rose [this message]
2006-09-27 17:07 ` iommu hypervisor hypothetical Olof Johansson
2006-09-27 18:25   ` John Rose
2006-09-27 18:40     ` Olof Johansson
2006-09-27 23:11     ` Benjamin Herrenschmidt

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=1159375671.19103.3.camel@sinatra.austin.ibm.com \
    --to=johnrose@austin.ibm.com \
    --cc=benh@kernel.crashing.org \
    --cc=linuxppc-dev@ozlabs.org \
    --cc=saleon@us.ibm.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).