From: Thomas Hellstrom <thellstrom@vmware.com>
To: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>,
Peter Zijlstra <peterz@infradead.org>,
Dave Airlie <airlied@linux.ie>,
intel-gfx <intel-gfx@lists.freedesktop.org>,
dri-devel <dri-devel@lists.freedesktop.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Ingo Molnar <mingo@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [BUG] completely bonkers use of set_need_resched + VM_FAULT_NOPAGE
Date: Fri, 13 Sep 2013 10:39:50 +0200 [thread overview]
Message-ID: <5232CF56.8060605@vmware.com> (raw)
In-Reply-To: <CAKMK7uFkav0b+8AYkm_3eT=d6T6wvstHuOXkTwFt_Do4YmijQA@mail.gmail.com>
On 09/13/2013 10:32 AM, Daniel Vetter wrote:
> On Fri, Sep 13, 2013 at 10:23 AM, Thomas Hellstrom
> <thellstrom@vmware.com> wrote:
>> As previously mentioned, copy_from_user should return -EFAULT, since the
>> VMAs are marked with VM_IO. It should not recurse into fault(), so evil
>> user-space looses.
> I haven't put a printk in the code to prove this, but gem mmap also
> sets VM_IO in drm_gem_mmap_obj. And we can very much hit our own fault
> handler and deadlock ....
If this is indeed true, I guess I need to accept the fact that my
solution is bad.
(and worse I can't blame not having my morning coffee).
I'll take a deeper look.
/Thomas
next prev parent reply other threads:[~2013-09-13 8:39 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-12 15:06 [BUG] completely bonkers use of set_need_resched + VM_FAULT_NOPAGE Peter Zijlstra
2013-09-12 15:11 ` Maarten Lankhorst
2013-09-12 15:14 ` Peter Zijlstra
2013-09-12 15:36 ` Daniel Vetter
2013-09-12 15:43 ` Peter Zijlstra
2013-09-12 15:58 ` Daniel Vetter
2013-09-12 16:22 ` Peter Zijlstra
2013-09-12 16:35 ` Chris Wilson
2013-09-12 20:30 ` Peter Zijlstra
2013-09-12 20:37 ` Thomas Gleixner
2013-09-12 19:52 ` Daniel Vetter
2013-09-12 19:58 ` Thomas Gleixner
2013-09-12 20:04 ` Daniel Vetter
2013-09-12 20:20 ` Thomas Gleixner
2013-09-12 20:23 ` Daniel Vetter
2013-09-12 20:39 ` Thomas Gleixner
2013-09-12 20:48 ` Thomas Hellstrom
2013-09-12 16:33 ` Thomas Hellstrom
2013-09-12 15:45 ` Maarten Lankhorst
2013-09-12 16:44 ` Thomas Hellstrom
2013-09-12 19:48 ` Daniel Vetter
2013-09-12 21:50 ` Maarten Lankhorst
2013-09-13 5:33 ` Thomas Hellstrom
2013-09-13 8:26 ` Daniel Vetter
2013-10-08 14:14 ` [RFC PATCH] drm/radeon: fixup locking inversion between mmap_sem and reservations Maarten Lankhorst
2013-10-08 14:33 ` Jerome Glisse
2013-10-08 14:45 ` Christian König
2013-10-08 14:55 ` Jerome Glisse
2013-10-08 16:29 ` Thomas Hellstrom
2013-10-08 16:47 ` Jerome Glisse
2013-10-08 16:58 ` Thomas Hellstrom
2013-10-09 12:36 ` [RFC PATCH v2] drm/radeon: fixup locking inversion between, " Maarten Lankhorst
2013-10-09 10:58 ` [RFC PATCH] drm/radeon: fixup locking inversion between " Maarten Lankhorst
2013-10-08 14:45 ` Maarten Lankhorst
2013-09-13 6:44 ` [BUG] completely bonkers use of set_need_resched + VM_FAULT_NOPAGE Thomas Hellstrom
2013-09-13 7:16 ` Maarten Lankhorst
2013-09-13 7:46 ` Thomas Hellstrom
2013-09-13 7:51 ` Maarten Lankhorst
2013-09-13 8:23 ` Thomas Hellstrom
2013-09-13 8:32 ` Daniel Vetter
2013-09-13 8:39 ` Thomas Hellstrom [this message]
2013-09-13 8:58 ` Maarten Lankhorst
2013-09-13 9:21 ` Thomas Hellstrom
2013-09-13 8:29 ` Peter Zijlstra
2013-09-13 8:41 ` Daniel Vetter
2013-09-13 9:00 ` Peter Zijlstra
2013-09-23 15:33 ` [RFC PATCH] drm/nouveau: fix nested locking in mmap handler Maarten Lankhorst
2013-09-24 7:22 ` Thomas Hellstrom
2013-09-24 7:34 ` Maarten Lankhorst
2013-09-24 8:20 ` Ingo Molnar
2013-09-24 9:03 ` Thomas Hellstrom
2013-09-24 9:36 ` Daniel Vetter
2013-09-24 10:11 ` Maarten Lankhorst
2013-09-24 10:33 ` Thomas Hellstrom
2013-09-24 11:32 ` Maarten Lankhorst
2013-09-24 17:04 ` Thomas Hellstrom
2013-09-24 9:43 ` Maarten Lankhorst
2013-09-24 17:53 ` Thomas Hellstrom
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=5232CF56.8060605@vmware.com \
--to=thellstrom@vmware.com \
--cc=airlied@linux.ie \
--cc=daniel.vetter@ffwll.ch \
--cc=dri-devel@lists.freedesktop.org \
--cc=intel-gfx@lists.freedesktop.org \
--cc=linux-kernel@vger.kernel.org \
--cc=maarten.lankhorst@canonical.com \
--cc=mingo@kernel.org \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
/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).