From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@freedesktop.org Subject: [Bug 90537] radeonsi bo/va conflict on RADEON_GEM_VA (rscreen->ws->buffer_from_handle returns NULL) Date: Wed, 27 May 2015 10:00:45 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1960230624==" Return-path: Received: from culpepper.freedesktop.org (unknown [131.252.210.165]) by gabe.freedesktop.org (Postfix) with ESMTP id 6D4966E7AB for ; Wed, 27 May 2015 03:00:45 -0700 (PDT) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org --===============1960230624== Content-Type: multipart/alternative; boundary="1432720845.cA31eaE0.14745"; charset="UTF-8" --1432720845.cA31eaE0.14745 Date: Wed, 27 May 2015 10:00:45 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable https://bugs.freedesktop.org/show_bug.cgi?id=3D90537 --- Comment #24 from Michel D=C3=A4nzer --- (In reply to Christian K=C3=B6nig from comment #23) > > How would it break backwards compatibility? >=20 > You would need to allow multiple mappings into the same address space per= BO. >=20 > Which is exactly what I've did for amdgpu, but IIRC that would break the > userspace interface because you won't return the mapped address any more > when you try to map it multiple times.... What would that break? It could result in the same BO having several representations in userspace, but (why) is that a problem? > > I'm not sure how not tracking the VA ranges per GEM handle could ever w= ork > > as expected with several GEM handles referencing the same BO. >=20 > Actually it can indeed never work correctly. What we just do all the time= is > trying to avoid the case that several GEM handles reference the same BO v= ery > hard. I'm afraid we can't always avoid that though, e.g. when sharing BOs between glamor and the Xorg driver. --=20 You are receiving this mail because: You are the assignee for the bug. --1432720845.cA31eaE0.14745 Date: Wed, 27 May 2015 10:00:45 +0000 MIME-Version: 1.0 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable

Commen= t # 24 on bug 90537<= /a> from Michel D=C3=A4nzer 
(In reply to Christian K=C3=B6nig from comment #23)
> > How would it break backwards compatibility?
>=20
> You would need to allow multiple mappings into the same address space =
per BO.
>=20
> Which is exactly what I've did for amdgpu, but IIRC that would break t=
he
> userspace interface because you won't return the mapped address any mo=
re
> when you try to map it multiple times....

What would that break? It could result in the same BO having several
representations in userspace, but (why) is that a problem?


> > I'm not sure how not tracking the VA ranges=
 per GEM handle could ever work
> > as expected with several GEM handles referencing the same BO.
>=20
> Actually it can indeed never work correctly. What we just do all the t=
ime is
> trying to avoid the case that several GEM handles reference the same B=
O very
> hard.

I'm afraid we can't always avoid that though, e.g. when sharing BOs between
glamor and the Xorg driver.

You are receiving this mail because: =20=20=20=20=20=20
  • You are the assignee for the bug.
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