linux_dsm_epyc7002/drivers/gpu/drm
Daniel Vetter 93a25a9e2d drm/i915: Disable full ppgtt by default
There are too many oustanding issues:

- Fence handling in the current code is broken. There's a patch series
  from me, but it's blocked on and extended review (which includes
  writing the testcases).

- IOMMU mapping handling is broken, we need to properly refcount it -
  currently it gets destroyed when the first vma is unbound, so way
  too early.

- There's a pending reset issue on snb. Since Mika's reset work and
  full ppgtt have been pulled in in separate branches and ended up
  intermittingly breaking each another it's unclear who's the exact
  culprit here.

- We still have persistent evidince of crazy recursion bugs through
  vma_unbind and ppgtt_relase, e.g.

  https://bugs.freedesktop.org/show_bug.cgi?id=73383

  This issue (and a few others meanwhile resolved) have blocked our
  performance measuring/tuning group since 3 months.

- Secure batch dispatching is broken. This is blocking Brad Volkin's
  command checker work since 3 months.

All these issues are confirmed to only happen when full ppgtt is
enabled, falling back to aliasing ppgtt resolves them. But even
aliasing ppgtt itself still has a regression:

- We currently unconditionally bind objects into the aliasing ppgtt,
  which means all priviledged objects like ringbuffers are visible to
  unpriviledged access again. On top of that this also breaks the
  command checker for aliasing ppgtt, since it can't hide the
  validated batch any more.

Furthermore topic/full-ppgtt has never been reviewed:

- Lifetime rules around vma unbinding/release are unclear, resulting
  into this awesome hack called ppgtt_release. Which seems to take the
  blame for most of the recursion fallout.

- Context/ring init works different on gpu reset than anywhere else.
  Such differeneces have in the past always lead to really hard to
  track down bugs.

- Aliasing ppgtt is treated in a bunch of places as a real address
  space, but it isn't - the real address space is always the global
  gtt in that case. This results in a bit a mess between contexts and
  ppgtt object, further complication the context/ppgtt/vma lifetime
  rules.

- We don't have any docs describing the overall concepts introduced
  with full ppgtt. A short, concise overview describing vmas and some
  of the strange bits around them (like the unbound vmas used by
  execbuf, or the new binding rules) really is needed.

Note that a lot of the post topic/full-ppgtt merge fallout has already
been addressed, this entire list here of 10 issues really only contains
the still outstanding issues.

Finally the 3.15 merge window is approaching and I think we need to
use the remaining time to ensure that our fallback option of using
aliasing ppgtt is in solid shape. Hence I think it's time to throw the
switch. While at it demote the helper from static inline status
because really.

Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-03-07 22:36:47 +01:00
..
armada Merge branch 'drm-armada-fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-cubox into drm-next 2014-01-29 09:38:32 +10:00
ast drm: ast,cirrus,mgag200: use drm_can_sleep 2014-01-29 10:51:52 +10:00
bochs drm/bochs: new driver 2013-12-23 11:02:39 +10:00
cirrus drm: ast,cirrus,mgag200: use drm_can_sleep 2014-01-29 10:51:52 +10:00
exynos drm/exynos: fix build error caused by removed drm core macros 2014-01-07 16:53:25 +09:00
gma500 Merge branch 'gma500-next' of git://github.com/patjak/drm-gma500 into drm-next 2014-01-29 09:35:48 +10:00
i2c
i810 drm: kill DRIVER_REQUIRE_AGP 2013-12-18 11:17:53 +10:00
i915 drm/i915: Disable full ppgtt by default 2014-03-07 22:36:47 +01:00
mga drivers: gpu: Include appropriate header file in mga_ioc32.c 2014-01-14 12:59:24 +10:00
mgag200 drm: ast,cirrus,mgag200: use drm_can_sleep 2014-01-29 10:51:52 +10:00
msm drm: store the gem vma offset manager in a typed pointer 2014-01-14 12:38:32 +10:00
nouveau Merge branch 'drm-nouveau-next' of git://anongit.freedesktop.org/git/nouveau/linux-2.6 into drm-next 2014-01-30 10:46:06 +10:00
omapdrm omapdrm patches for 3.14 2014-01-29 09:37:47 +10:00
panel drm/panel: update EDID BLOB in panel_simple_get_modes() 2014-01-14 16:02:02 +01:00
qxl gpu: fix qxl missing crc32_le 2014-01-14 13:08:37 +10:00
r128 drivers: gpu: Include appropriate header file in r128_ioc32.c 2014-01-14 13:05:37 +10:00
radeon drm/radeon/dce8: workaround for atom BlankCrtc table 2014-01-29 16:10:54 -05:00
rcar-du Merge branch 'drm/next/du' of git://linuxtv.org/pinchartl/fbdev into drm-next 2013-12-23 10:42:36 +10:00
savage drm: Kill DRM_*MEMORYBARRIER 2013-12-18 11:35:21 +10:00
shmobile drm/shmob: call drm_put_dev directly from ->remove hook 2013-12-18 11:05:46 +10:00
sis drivers: gpu: Mark function as static in sis_drv.c 2014-01-14 13:04:33 +10:00
tdfx
tegra drm/tegra: Changes for v3.14-rc1 (update) 2014-01-29 12:03:56 +10:00
tilcdc drm: store the gem vma offset manager in a typed pointer 2014-01-14 12:38:32 +10:00
ttm Merge branch 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2014-01-20 10:21:54 +10:00
udl drm: Push dirtyfb ioctl kms locking down to drivers 2013-12-18 10:49:08 +10:00
via drivers: gpu: Mark function as static in via_drv.c 2014-01-14 13:05:00 +10:00
vmwgfx drm/vmwgfx: Fix recently introduced sparse / smatch warnings and errors 2014-01-21 13:22:18 +01:00
ati_pcigart.c
drm_agpsupport.c drm: rip out DRM_AGP_MEM and DRM_AGP_KERN 2013-12-18 11:32:55 +10:00
drm_auth.c
drm_buffer.c drm: Kill DRM_COPY_(TO|FROM)_USER 2013-12-18 11:35:01 +10:00
drm_bufs.c drm: rip out drm_core_has_AGP 2013-12-18 11:20:04 +10:00
drm_cache.c
drm_context.c
drm_crtc_helper.c drm/tegra: Changes for v3.14-rc1 (update) 2014-01-29 12:03:56 +10:00
drm_crtc.c drm: expose subpixel order name routine v3 2014-02-12 18:53:04 +01:00
drm_debugfs.c
drm_dma.c
drm_dp_helper.c
drm_drv.c drm: Kill file_priv->ioctl_count tracking 2013-12-18 11:42:13 +10:00
drm_edid_load.c drm/edid: Make edid_load() return a void * 2013-12-18 10:42:13 +10:00
drm_edid.c drm/edid: Populate picture aspect ratio for CEA modes 2014-01-20 18:32:21 +01:00
drm_encoder_slave.c
drm_fb_cma_helper.c
drm_fb_helper.c drm: export cmdline and preferred mode functions from fb helper 2014-02-12 23:42:16 +01:00
drm_flip_work.c kfifo API type safety 2013-11-15 09:32:23 +09:00
drm_fops.c drm: remove dev->vma_count 2013-12-18 11:43:29 +10:00
drm_gem_cma_helper.c
drm_gem.c drm/gem: Always initialize the gem object in object_init 2014-01-21 10:19:58 +01:00
drm_global.c
drm_hashtab.c
drm_info.c drm: remove dev->vma_count 2013-12-18 11:43:29 +10:00
drm_ioc32.c
drm_ioctl.c
drm_irq.c drm/radeon: Move the early vblank IRQ fixup to radeon_get_crtc_scanoutpos() 2014-01-20 12:21:35 +02:00
drm_lock.c
drm_memory.c drm: rip out DRM_AGP_MEM and DRM_AGP_KERN 2013-12-18 11:32:55 +10:00
drm_mipi_dsi.c drm: Add MIPI DSI bus support 2013-12-17 18:09:43 +01:00
drm_mm.c
drm_modes.c Revert "drm: copy mode type in drm_mode_connector_list_update()" 2014-01-14 12:50:49 +10:00
drm_panel.c drm: Add panel support 2013-12-17 18:09:46 +01:00
drm_pci.c drm: remove global_mutex locking around agp_init 2013-12-18 11:27:29 +10:00
drm_platform.c drm: restrict the device list for shadow attached drivers 2013-12-18 11:08:36 +10:00
drm_prime.c
drm_rect.c
drm_scatter.c
drm_stub.c Merge branch 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2014-01-20 10:21:54 +10:00
drm_sysfs.c drm/sysfs: fix OOM verification 2013-11-28 14:35:23 +10:00
drm_trace_points.c
drm_trace.h
drm_usb.c drivers: gpu: Include appropriate header file in drm_usb.c 2014-01-14 12:53:41 +10:00
drm_vm.c drm: remove dev->vma_count 2013-12-18 11:43:29 +10:00
drm_vma_manager.c
Kconfig drm/bochs: new driver 2013-12-23 11:02:39 +10:00
Makefile drm/bochs: new driver 2013-12-23 11:02:39 +10:00
README.drm

************************************************************
* For the very latest on DRI development, please see:      *
*     http://dri.freedesktop.org/                          *
************************************************************

The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).

The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:

    1. The DRM provides synchronized access to the graphics hardware via
       the use of an optimized two-tiered lock.

    2. The DRM enforces the DRI security policy for access to the graphics
       hardware by only allowing authenticated X11 clients access to
       restricted regions of memory.

    3. The DRM provides a generic DMA engine, complete with multiple
       queues and the ability to detect the need for an OpenGL context
       switch.

    4. The DRM is extensible via the use of small device-specific modules
       that rely extensively on the API exported by the DRM module.


Documentation on the DRI is available from:
    http://dri.freedesktop.org/wiki/Documentation
    http://sourceforge.net/project/showfiles.php?group_id=387
    http://dri.sourceforge.net/doc/

For specific information about kernel-level support, see:

    The Direct Rendering Manager, Kernel Support for the Direct Rendering
    Infrastructure
    http://dri.sourceforge.net/doc/drm_low_level.html

    Hardware Locking for the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/hardware_locking_low_level.html

    A Security Analysis of the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/security_low_level.html