From: Keith Packard <keithp@keithp.com>
To: Chris Wilson <chris@chris-wilson.co.uk>, intel-gfx@lists.freedesktop.org
Subject: Re: [PATCH 2/2] drm/i915: Disable page-faults around the fast pwrite/pread paths
Date: Sat, 09 Jul 2011 13:24:02 -0700 [thread overview]
Message-ID: <yunvcvbfbj1.fsf@aiko.keithp.com> (raw)
In-Reply-To: <1310200731-18086-2-git-send-email-chris@chris-wilson.co.uk>
[-- Attachment #1.1: Type: text/plain, Size: 625 bytes --]
On Sat, 9 Jul 2011 09:38:51 +0100, Chris Wilson <chris@chris-wilson.co.uk> wrote:
> + /* We have to disable faulting here in case the user address
> + * is really a GTT mapping and so we can not enter
> + * i915_gem_fault() whilst already holding struct_mutex.
> + */
I would (far, far) rather disallow pread through the GTT
mapping. There's no credible reason to allow it. Is there some
reasonably fast way to detect that these addresses are within the GTT
and just bail?
Any performance penalty that serves solely to enable abuse of the
interface is not reasonable.
--
keith.packard@intel.com
[-- Attachment #1.2: Type: application/pgp-signature, Size: 189 bytes --]
[-- Attachment #2: Type: text/plain, Size: 159 bytes --]
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx
next prev parent reply other threads:[~2011-07-09 20:24 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-09 8:38 [PATCH 1/2] drm/i915: Prefault all pages for pread and pwrite Chris Wilson
2011-07-09 8:38 ` [PATCH 2/2] drm/i915: Disable page-faults around the fast pwrite/pread paths Chris Wilson
2011-07-09 14:41 ` Eric Anholt
2011-07-09 17:40 ` Chris Wilson
2011-07-09 20:24 ` Keith Packard [this message]
2011-07-09 20:50 ` Chris Wilson
2011-07-09 21:06 ` Keith Packard
2011-07-09 21:23 ` Chris Wilson
2011-07-09 22:07 ` Keith Packard
2011-07-11 16:51 ` Chris Wilson
2011-07-11 19:55 ` Keith Packard
2011-07-10 18:45 ` Eric Anholt
2011-07-10 20:29 ` Keith Packard
2011-07-09 20:21 ` [PATCH 1/2] drm/i915: Prefault all pages for pread and pwrite Keith Packard
2011-07-09 20:31 ` Chris Wilson
2011-07-10 1:40 ` Ben Widawsky
2011-07-10 8:08 ` Chris Wilson
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=yunvcvbfbj1.fsf@aiko.keithp.com \
--to=keithp@keithp.com \
--cc=chris@chris-wilson.co.uk \
--cc=intel-gfx@lists.freedesktop.org \
/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).