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be72615bcf
If during the freeing of an object the unbind is interrupted by a system
call, which is quite possible if we have outstanding GPU writes that
must be flushed, the unbind is silently aborted. This still leaves the
AGP region and backing pages allocated, and perhaps more importantly,
the object remains upon the various lists exposing us to memory
corruption.
I think this is the cause behind the use-after-free, such as
Bug 15664 - Graphics hang and kernel backtrace when starting Azureus
with Compiz enabled
https://bugzilla.kernel.org/show_bug.cgi?id=15664
v2: Daniel Vetter reminded me that kernel space programming is never easy.
We cannot simply spin to clear the pending signal and so must deferred
the freeing of the object until later.
v3: Run from the top level retire requests.
v4: Tested with P(return -ERESTARTSYS)=.5 from i915_gem_do_wait_request()
v5: Rebase against Eric's for-linus tree.
v6: Refactor, split and add a comment about avoiding unbounded recursion.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
|
||
|---|---|---|
| .. | ||
| i2c | ||
| i810 | ||
| i830 | ||
| i915 | ||
| mga | ||
| nouveau | ||
| r128 | ||
| radeon | ||
| savage | ||
| sis | ||
| tdfx | ||
| ttm | ||
| via | ||
| vmwgfx | ||
| ati_pcigart.c | ||
| drm_agpsupport.c | ||
| drm_auth.c | ||
| drm_buffer.c | ||
| drm_bufs.c | ||
| drm_cache.c | ||
| drm_context.c | ||
| drm_crtc.c | ||
| drm_crtc_helper.c | ||
| drm_debugfs.c | ||
| drm_dma.c | ||
| drm_dp_i2c_helper.c | ||
| drm_drawable.c | ||
| drm_drv.c | ||
| drm_edid.c | ||
| drm_encoder_slave.c | ||
| drm_fb_helper.c | ||
| drm_fops.c | ||
| drm_gem.c | ||
| drm_hashtab.c | ||
| drm_info.c | ||
| drm_ioc32.c | ||
| drm_ioctl.c | ||
| drm_irq.c | ||
| drm_lock.c | ||
| drm_memory.c | ||
| drm_mm.c | ||
| drm_modes.c | ||
| drm_pci.c | ||
| drm_platform.c | ||
| drm_proc.c | ||
| drm_scatter.c | ||
| drm_sman.c | ||
| drm_stub.c | ||
| drm_sysfs.c | ||
| drm_trace.h | ||
| drm_trace_points.c | ||
| drm_vm.c | ||
| Kconfig | ||
| Makefile | ||
| 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