A bunch of warnings fire on some ->irq_postinstall hooks since those
can enable interrupts (e.g. rps interrupts). And then our ordering
self-checks fire and complain.
To fix that set the tracking boolen before enabling the irqs with
drm_irq_install. Quoting the discussion with Jesse why that's safe:
On Tue, Aug 26, 2014 at 11:18 PM, Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
> Yes, it might work, but if you look through the history, we set this
> field carefully; first to true in the irq_init code, then to false only
> after the irq_install completes. So I think your fragility arguments
> apply to this change too.
Well we've done it in 4 commits or so, but currently we have:
- Set irqs_disabled to true early in driver load to make sure checks
that. That's done in irq_init, which is totally not the function that
enables interrupts, only the function that initializes all the vtables
and similar things. We actually have a fairly sane naming scheme
nowadays (not fully consistent ofc): _init is sw setup,
_enable/_hw_init is the actual hw setup. That is done in
95f25beddb
- Set irqs_disabled to false right after the irqs are actually
enabled. This is done in ed2e6df189
So my change should only move the flag change over the ->preinstall
and ->postinstall hooks. I've done a little audit and didn't spot
anything amiss. Furthermore the runtime pm setup already clears
irqs_disabled _before_ calling these two hooks.
This regression has been introduced in
commit ed2e6df189
Author: Jesse Barnes <jbarnes@virtuousgeek.org>
Date: Fri Jun 20 09:39:36 2014 -0700
drm/i915: clear pm._irqs_disabled field after installing IRQs
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk> # gm45, ilk
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
************************************************************
* 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
4868b45de1