[Mesa-dev] [PATCH 3/3] radeon/uvd: use PIPE_USAGE_STAGING for msg&fb buffers

2014-09-11 Thread Christian König
From: Christian König That better matches the actual userspace use case, the kernel will force it to VRAM if the hardware requires it. Signed-off-by: Christian König --- src/gallium/drivers/radeon/radeon_uvd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/gallium/driv

[Mesa-dev] [PATCH 1/3] radeon/video: use more of the common buffer code v2

2014-09-11 Thread Christian König
From: Christian König In preparation to using buffers clears with the hw engine(s). v2: split out flipping to using hw buffer clears. Signed-off-by: Christian König --- src/gallium/drivers/radeon/radeon_uvd.c| 40 ++- src/gallium/drivers/radeon/radeon_vce.c| 17

[Mesa-dev] [PATCH 2/3] radeon/video: use the hw to initial clear the buffers

2014-09-11 Thread Christian König
From: Christian König Less CPU overhead and avoids contention over CPU accessible memory on startup. Signed-off-by: Christian König --- src/gallium/drivers/radeon/radeon_uvd.c | 6 +++--- src/gallium/drivers/radeon/radeon_video.c | 10 -- src/gallium/drivers/radeon/radeon_video.h |

[Mesa-dev] Compiling of shader gets stuck in infinite loop

2014-09-11 Thread Iago Toral Quiroga
Hi, I have been looking into this bug: Compiling of shader gets stuck in infinite loop https://bugs.freedesktop.org/show_bug.cgi?id=78468 Although this occurs at link time when the Intel driver has run some of its specific lowering passes, it looks like the problem could hit other drivers if the

Re: [Mesa-dev] [PATCH] radeonsi: Program RASTER_CONFIG for harvested GPUs v4

2014-09-11 Thread Michel Dänzer
On 10.09.2014 22:59, Tom Stellard wrote: + /* Always use the default config when all backends are enabled. */ + if (rb_mask && util_bitcount(rb_mask) < max_backends) { + /* XXX: I can't figure out what the *_XSEL and *_YSEL +

Re: [Mesa-dev] [PATCH 1/3] radeon/video: use more of the common buffer code v2

2014-09-11 Thread Michel Dänzer
On 11.09.2014 16:55, Christian König wrote: From: Christian König In preparation to using buffers clears with the hw engine(s). v2: split out flipping to using hw buffer clears. Thanks! The series is Reviewed-by: Michel Dänzer -- Earthling Michel Dänzer| http

Re: [Mesa-dev] [PATCH] radeonsi: Simplify si_dma_copy_tile function

2014-09-11 Thread Michel Dänzer
On 11.09.2014 00:28, Grigori Goronzy wrote: On 10.09.2014 10:54, Michel Dänzer wrote: From: Michel Dänzer + array_mode = si_array_mode(rtiled->surface.level[tiled_lvl].mode); Wouldn't it be more consistent to pull the array_mode from the tile mode array like other parameters? I don't

Re: [Mesa-dev] [PATCH] radeonsi: Fix si_dma_copy(_tile) for compressed formats

2014-09-11 Thread Michel Dänzer
On 11.09.2014 07:05, Marek Olšák wrote: Sorry, the function is too confusing for me to understand it, but it looks good. Thanks, but unfortunately, it breaks the fbo-generatemipmap-formats test with compressed formats for some reason. Investigating that now. I think it would be cleaner to

[Mesa-dev] [Bug 83669] fix build with gcc link time optimizer

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83669 --- Comment #10 from Marc Dietrich --- I check with -g -O0 and debug symbols are generated, but I can't tell about their usefulness. Compiling with --enable-debug fails though because -DDEBUG seems to do strange things in combination with --enabl

[Mesa-dev] [Bug 83669] fix build with gcc link time optimizer

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83669 --- Comment #11 from Marc Dietrich --- sorry for spamming this bug, here is a better patch to fix the problem diff --git a/src/mesa/Makefile.am b/src/mesa/Makefile.am index e71bccb..bbdb36f 100644 --- a/src/mesa/Makefile.am +++ b/src/mesa/Makefi

[Mesa-dev] [Bug 70599] [SNB/IVB/HSW Bisected]Piglit glx/GLX_ARB_create_context/current_with_no_framebuffer segfault

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=70599 Tapani Pälli changed: What|Removed |Added Status|NEW |RESOLVED Resolution|---

Re: [Mesa-dev] [PATCH 1/5] mesa: Have validate_uniform_parameters return the gl_uniform_storage pointer

2014-09-11 Thread Erik Faye-Lund
On Sat, Aug 2, 2014 at 4:09 AM, Ian Romanick wrote: > diff --git a/src/mesa/main/uniform_query.cpp b/src/mesa/main/uniform_query.cpp > index 609d94b..7b089fa 100644 > --- a/src/mesa/main/uniform_query.cpp > +++ b/src/mesa/main/uniform_query.cpp > @@ -266,30 +265,32 @@ validate_uniform_parameters(s

Re: [Mesa-dev] [PATCH 1/5] mesa: Have validate_uniform_parameters return the gl_uniform_storage pointer

2014-09-11 Thread Erik Faye-Lund
On Thu, Sep 11, 2014 at 1:27 PM, Erik Faye-Lund wrote: > On Sat, Aug 2, 2014 at 4:09 AM, Ian Romanick wrote: >> diff --git a/src/mesa/main/uniform_query.cpp >> b/src/mesa/main/uniform_query.cpp >> index 609d94b..7b089fa 100644 >> --- a/src/mesa/main/uniform_query.cpp >> +++ b/src/mesa/main/unifo

Re: [Mesa-dev] [PATCH 1/5] mesa: Have validate_uniform_parameters return the gl_uniform_storage pointer

2014-09-11 Thread Tapani Pälli
On 09/11/2014 02:27 PM, Erik Faye-Lund wrote: > On Sat, Aug 2, 2014 at 4:09 AM, Ian Romanick wrote: >> diff --git a/src/mesa/main/uniform_query.cpp >> b/src/mesa/main/uniform_query.cpp >> index 609d94b..7b089fa 100644 >> --- a/src/mesa/main/uniform_query.cpp >> +++ b/src/mesa/main/uniform_query.c

Re: [Mesa-dev] [PATCH 1/5] mesa: Have validate_uniform_parameters return the gl_uniform_storage pointer

2014-09-11 Thread Erik Faye-Lund
On Thu, Sep 11, 2014 at 2:00 PM, Tapani Pälli wrote: > On 09/11/2014 02:27 PM, Erik Faye-Lund wrote: >> On Sat, Aug 2, 2014 at 4:09 AM, Ian Romanick wrote: >>> diff --git a/src/mesa/main/uniform_query.cpp >>> b/src/mesa/main/uniform_query.cpp >>> index 609d94b..7b089fa 100644 >>> --- a/src/mesa/

Re: [Mesa-dev] [PATCH] mesa: check that uniform exists in glUniform* functions

2014-09-11 Thread Erik Faye-Lund
On Thu, Aug 28, 2014 at 9:58 AM, Tapani Pälli wrote: > Remap table for uniforms may contain empty entries when using explicit > uniform locations. If no active/inactive variable exists with given > location, remap table contains NULL. > > Signed-off-by: Tapani Pälli > --- > src/mesa/main/uniform

Re: [Mesa-dev] [PATCH] mesa: check that uniform exists in glUniform* functions

2014-09-11 Thread Tapani
On 09/11/2014 03:12 PM, Erik Faye-Lund wrote: On Thu, Aug 28, 2014 at 9:58 AM, Tapani Pälli wrote: Remap table for uniforms may contain empty entries when using explicit uniform locations. If no active/inactive variable exists with given location, remap table contains NULL. Signed-off-by: Tapa

[Mesa-dev] [PATCH] replace file specific compiler optimization with inline attibute

2014-09-11 Thread Marc Dietrich
File specific optimization as used for src/mesa/main/streaming-load-memcpy.c currently will cause problems with LTO in the future (see: https://bugs.freedesktop.org/show_bug.cgi?id=83669). Replace it with in-file target specification. This only works for gcc for now. The intel compiler has __attri

[Mesa-dev] [Bug 83570] Glyphy demo throws unhandled Integer division by zero exception

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83570 --- Comment #13 from Roland Scheidegger --- (In reply to comment #12) > Roland, > Perhaps you can help me here. I'm looking at udiv_emit_cpu and I'm just > not getting it. The comment says: > > /* udiv by zero is guaranteed to return 0xfff

[Mesa-dev] [Bug 83570] Glyphy demo throws unhandled Integer division by zero exception

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83570 --- Comment #14 from rcond...@hotmail.com --- (In reply to comment #13) > (comparison masks are either all ones or all zeros). AHH!!! That was the piece I was missing. My hair follicles thank you. -- You are receiving this mail because: You are

Re: [Mesa-dev] [PATCH] replace file specific compiler optimization with inline attibute

2014-09-11 Thread Matt Turner
On Thu, Sep 11, 2014 at 6:58 AM, Marc Dietrich wrote: > File specific optimization as used for src/mesa/main/streaming-load-memcpy.c > currently will cause problems with LTO in the future > (see: https://bugs.freedesktop.org/show_bug.cgi?id=83669). Replace it with > in-file target specification.

[Mesa-dev] [Bug 83777] New: [regression] ilo fails to build

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83777 Priority: medium Bug ID: 83777 CC: olva...@gmail.com Assignee: mesa-dev@lists.freedesktop.org Summary: [regression] ilo fails to build Severity: normal Classification: Unclas

[Mesa-dev] [Bug 83631] /usr/include/GL/glxext.h:480:143: error: 'GLintptr' has not been declared

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83631 --- Comment #3 from Brian Paul --- #include "GL/glx.h" should pull in GL/gl.h (line 32) which should include GL/glext.h So by time we hit the use of GLintptr, it should have been defined. When I compile a trivial test program like this: #incl

Re: [Mesa-dev] [PATCH] i965/vec4: Only examine virtual_grf_end for GRF sources

2014-09-11 Thread Kenneth Graunke
On Wednesday, September 10, 2014 06:01:19 PM Ian Romanick wrote: > From: Ian Romanick > > If the source is not a GRF, it could have a register >= virtual_grf_count. > Accessing virtual_grf_end with such a register would lead to > out-of-bounds access. Make sure the source is a GRF before accessi

Re: [Mesa-dev] [PATCH 1/5] mesa: Have validate_uniform_parameters return the gl_uniform_storage pointer

2014-09-11 Thread Ian Romanick
On 09/11/2014 05:09 AM, Erik Faye-Lund wrote: > On Thu, Sep 11, 2014 at 2:00 PM, Tapani Pälli wrote: >> On 09/11/2014 02:27 PM, Erik Faye-Lund wrote: >>> On Sat, Aug 2, 2014 at 4:09 AM, Ian Romanick wrote: diff --git a/src/mesa/main/uniform_query.cpp b/src/mesa/main/uniform_query.cpp >

Re: [Mesa-dev] [PATCH] radeonsi: Program RASTER_CONFIG for harvested GPUs v4

2014-09-11 Thread Tom Stellard
On Thu, Sep 11, 2014 at 05:24:03PM +0900, Michel Dänzer wrote: > On 10.09.2014 22:59, Tom Stellard wrote: > > > >+/* Always use the default config when all backends are enabled. > >*/ > >+if (rb_mask && util_bitcount(rb_mask) < max_backends) { > >+/* XXX

Re: [Mesa-dev] [PATCH] mesa: check that uniform exists in glUniform* functions

2014-09-11 Thread Ian Romanick
On 08/28/2014 12:58 AM, Tapani Pälli wrote: > Remap table for uniforms may contain empty entries when using explicit > uniform locations. If no active/inactive variable exists with given > location, remap table contains NULL. > > Signed-off-by: Tapani Pälli > --- > src/mesa/main/uniform_query.cp

Re: [Mesa-dev] [PATCH 1/5] mesa: Have validate_uniform_parameters return the gl_uniform_storage pointer

2014-09-11 Thread Erik Faye-Lund
On Thu, Sep 11, 2014 at 8:35 PM, Ian Romanick wrote: > On 09/11/2014 05:09 AM, Erik Faye-Lund wrote: >> On Thu, Sep 11, 2014 at 2:00 PM, Tapani Pälli wrote: >>> On 09/11/2014 02:27 PM, Erik Faye-Lund wrote: On Sat, Aug 2, 2014 at 4:09 AM, Ian Romanick wrote: > diff --git a/src/mesa/main

Re: [Mesa-dev] [PATCH] mesa: check that uniform exists in glUniform* functions

2014-09-11 Thread Erik Faye-Lund
On Thu, Sep 11, 2014 at 8:39 PM, Ian Romanick wrote: > On 08/28/2014 12:58 AM, Tapani Pälli wrote: >> Remap table for uniforms may contain empty entries when using explicit >> uniform locations. If no active/inactive variable exists with given >> location, remap table contains NULL. >> >> Signed-o

Re: [Mesa-dev] Compiling of shader gets stuck in infinite loop

2014-09-11 Thread Mike Stroyan
I have looked at this problem quite a bit but never got to the bottom of it. This problem really started to show with commit 857f3a6 - "glsl: Ignore loop-too-large heuristic if there's bad variable indexing." That commit makes many more loops unroll. Here is another example piglit shader_runner tes

[Mesa-dev] [PATCH] nv50,nvc0: fix Z24 formats

2014-09-11 Thread David Heidelberger
also fixes nv50_blit_eng2d_get_mask for PIPE_FORMAT_X8Z24_UNORM Tested-by: Tiziano Bacocco (on NVC0) Signed-off-by: David Heidelberger --- src/gallium/drivers/nouveau/nv50/nv50_blit.h| 26 - src/gallium/drivers/nouveau/nv50/nv50_surface.c | 1 + src/gallium/drive

Re: [Mesa-dev] [PATCH] nv50,nvc0: fix Z24 formats

2014-09-11 Thread Ilia Mirkin
On Thu, Sep 11, 2014 at 5:45 PM, David Heidelberger wrote: > also fixes nv50_blit_eng2d_get_mask for PIPE_FORMAT_X8Z24_UNORM Can you explain the problem a little bit and what the end-effect of this fix is? If not, that's OK, I can probably work it out... > > Tested-by: Tiziano Bacocco (on NVC0)

Re: [Mesa-dev] [PATCH] nv50,nvc0: fix Z24 formats

2014-09-11 Thread David Heidelberger
I started using PIPE_FORMAT_X8Z24_UNORM and PIPE_FORMAT_S8_UINT_Z24_UNORM in Nine state tracker. As it shows up, it caused problems on NVC0 (PGRAPH errors), which are solved by adding PIPE_FORMAT_X8Z24_UNORM in nvc0_miptree.c. By quick grep I also noticed, there is lot places in nv50, where m

[Mesa-dev] [PATCH] Copy Layered field in reuse_framebuffer_texture_attachment

2014-09-11 Thread Vincent Lejeune
Fix #83596 https://bugs.freedesktop.org/show_bug.cgi?id=83596 --- src/mesa/main/fbobject.c | 1 + 1 file changed, 1 insertion(+) diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c index ae3a418..5eaf1a3 100644 --- a/src/mesa/main/fbobject.c +++ b/src/mesa/main/fbobject.c @@ -2299,6

Re: [Mesa-dev] [PATCH v2 08/13] mesa/format_utils: Add a general format conversion function

2014-09-11 Thread Dieter Nützel
Am 15.08.2014 04:50, schrieb Jason Ekstrand: On Aug 14, 2014 7:13 PM, "Dieter Nützel" wrote: > > Am 15.08.2014 02:36, schrieb Dave Airlie: > On 08/02/2014 02:11 PM, Jason Ekstrand wrote: > > > Most format conversion operations required by GL can be performed by > con

Re: [Mesa-dev] [PATCH] Copy Layered field in reuse_framebuffer_texture_attachment

2014-09-11 Thread Chris Forbes
It would be good to also have a piglit test which demonstrates this bad behavior. Patch is: Reviewed-by: Chris Forbes On Fri, Sep 12, 2014 at 9:42 AM, Vincent Lejeune wrote: > Fix #83596 > https://bugs.freedesktop.org/show_bug.cgi?id=83596 > --- > src/mesa/main/fbobject.c | 1 + > 1 file chan

Re: [Mesa-dev] Mesa 10.3 release plan

2014-09-11 Thread Ian Romanick
On 09/10/2014 05:45 AM, Emil Velikov wrote: > Hello all, > > The original plan from Ian was to have four release candidates prior to the > final release. From what I can see there has been no serious amount of patches > nominated for 10.3-rc4, so I'm planning to keep with the plan and release 10.3

Re: [Mesa-dev] [PATCH v2 08/13] mesa/format_utils: Add a general format conversion function

2014-09-11 Thread Jason Ekstrand
On Thu, Sep 11, 2014 at 2:55 PM, Dieter Nützel wrote: > Am 15.08.2014 04:50, schrieb Jason Ekstrand: > > On Aug 14, 2014 7:13 PM, "Dieter Nützel" >> wrote: >> > >> > Am 15.08.2014 02:36, schrieb Dave Airlie: >> > >> On 08/02/2014 02:11 PM, Jason Ekstrand wrote: >> > >> > >>

Re: [Mesa-dev] [PATCH] Generate a warning when not writing gl_Position with GLES.

2014-09-11 Thread Anuj Phogat
On Wed, Sep 10, 2014 at 8:20 PM, Kalyan Kondapally wrote: > With GLES we don't give any kind of warning in case we don't > write to gl_position. This patch makes changes so that we > generate a warning in case of GLES (VER < 300) and an error > in case of GL. > > Signed-off-by: Kalyan Kondapally

Re: [Mesa-dev] [PATCH v2 08/13] mesa/format_utils: Add a general format conversion function

2014-09-11 Thread Jason Ekstrand
On Thu, Sep 11, 2014 at 3:31 PM, Jason Ekstrand wrote: > > > On Thu, Sep 11, 2014 at 2:55 PM, Dieter Nützel > wrote: > >> Am 15.08.2014 04:50, schrieb Jason Ekstrand: >> >> On Aug 14, 2014 7:13 PM, "Dieter Nützel" >>> wrote: >>> > >>> > Am 15.08.2014 02:36, schrieb Dave Airlie: >>> > >>> >

Re: [Mesa-dev] [PATCH v2 08/13] mesa/format_utils: Add a general format conversion function

2014-09-11 Thread Dieter Nützel
Am 12.09.2014 00:31, schrieb Jason Ekstrand: On Thu, Sep 11, 2014 at 2:55 PM, Dieter Nützel wrote: Am 15.08.2014 04:50, schrieb Jason Ekstrand: On Aug 14, 2014 7:13 PM, "Dieter Nützel" wrote: Am 15.08.2014 02:36, schrieb Dave Airlie: On 08/02/2014 02:11 PM, Jason Ekstrand wrote: Most

Re: [Mesa-dev] [PATCH v2 08/13] mesa/format_utils: Add a general format conversion function

2014-09-11 Thread Jason Ekstrand
On Thu, Sep 11, 2014 at 3:53 PM, Dieter Nützel wrote: > Am 12.09.2014 00:31, schrieb Jason Ekstrand: > > On Thu, Sep 11, 2014 at 2:55 PM, Dieter Nützel >> wrote: >> >> Am 15.08.2014 04:50, schrieb Jason Ekstrand: >>> >>> On Aug 14, 2014 7:13 PM, "Dieter Nützel" wrote: > > A

[Mesa-dev] [Bug 83777] [regression] ilo fails to build

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83777 --- Comment #1 from sarnex --- Exact same issue here. -- You are receiving this mail because: You are the assignee for the bug. ___ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.fr

[Mesa-dev] [Bug 83777] [regression] ilo fails to build

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83777 sarnex changed: What|Removed |Added Severity|normal |major Priority|medium

[Mesa-dev] [Bug 83777] [regression] ilo fails to build

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83777 sarnex changed: What|Removed |Added Severity|major |critical -- You are receiving this mail becaus

[Mesa-dev] [Bug 83777] [regression] ilo fails to build

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83777 Chia-I Wu changed: What|Removed |Added Status|NEW |RESOLVED Resolution|---

[Mesa-dev] [Bug 83785] New: Shader branches excluded by uniform values are not optimized out

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83785 Priority: medium Bug ID: 83785 Assignee: mesa-dev@lists.freedesktop.org Summary: Shader branches excluded by uniform values are not optimized out Severity: major Classifi

[Mesa-dev] [Bug 83785] Shader branches excluded by uniform values are not optimized out

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83785 Roland Scheidegger changed: What|Removed |Added Severity|major |enhancement Component|Mesa

Re: [Mesa-dev] [PATCH] mesa: check that uniform exists in glUniform* functions

2014-09-11 Thread Tapani Pälli
On 09/11/2014 09:39 PM, Ian Romanick wrote: > On 08/28/2014 12:58 AM, Tapani Pälli wrote: >> Remap table for uniforms may contain empty entries when using explicit >> uniform locations. If no active/inactive variable exists with given >> location, remap table contains NULL. >> >> Signed-off-by: Tap

[Mesa-dev] [PATCH 1/2] i965: Skip allocating UNIFORM file storage for uniforms of size 0.

2014-09-11 Thread Kenneth Graunke
Samplers take up zero slots and therefore don't exist in the params array, nor are they included in stage_prog_data->nr_params. There's no need to store their size in param_size, as it's only used for dealing with arrays of "real" uniforms (ones uploaded as shader constants). We run into all kind

[Mesa-dev] [PATCH 2/2] i965/vec4: Make type_size() return 0 for samplers.

2014-09-11 Thread Kenneth Graunke
The FS backend has always used 0, and the VS backend has always used 1. I think 1 is just working around other problems, and is incorrect. Samplers are baked in; nothing uses the UNIFORM register we would create, and we shouldn't upload any constant values for them. Fixes ES3-CTS.shaders.struct.un

[Mesa-dev] [Bug 70599] [SNB/IVB/HSW Bisected]Piglit glx/GLX_ARB_create_context/current_with_no_framebuffer segfault

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=70599 lu hua changed: What|Removed |Added Status|RESOLVED|VERIFIED --- Comment #3 from lu hua --- (In re

[Mesa-dev] [Bug 83777] [regression] ilo fails to build

2014-09-11 Thread bugzilla-daemon
https://bugs.freedesktop.org/show_bug.cgi?id=83777 Fabio Pedretti changed: What|Removed |Added Status|RESOLVED|VERIFIED -- You are receiving this mai

[Mesa-dev] [PATCH] i965: Check if unsynchronized map fails in BufferSubData.

2014-09-11 Thread Kenneth Graunke
This patch fixes a NULL pointer dereference in a test case which allocates piles of buffers without ever freeing them, and repeatedly tries to upload/fetch data to/from those buffers, without doing any other work (such as rendering). The same problem exists in a variety of other places, some of wh

Re: [Mesa-dev] [PATCH] i965: Check if unsynchronized map fails in BufferSubData.

2014-09-11 Thread Tapani Pälli
Reviewed-by: Tapani Pälli On 09/12/2014 09:43 AM, Kenneth Graunke wrote: > This patch fixes a NULL pointer dereference in a test case which > allocates piles of buffers without ever freeing them, and repeatedly > tries to upload/fetch data to/from those buffers, without doing any > other work (su