The fbdev test of IGT may write after EOF, which lead to out-of-bound
access for drm drivers with fbdev-generic. For example, run fbdev test
on a x86+ast2400 platform, with 1680x1050 resolution, will cause the
linux kernel hang with the following call trace:
Oops: 0000 [#1] PREEMPT SMP PTI
[IGT] fbdev: starting subtest eof
Workqueue: events drm_fb_helper_damage_work [drm_kms_helper]
[IGT] fbdev: starting subtest nullptr
RIP: 0010:memcpy_erms+0xa/0x20
RSP: 0018:ffffa17d40167d98 EFLAGS: 00010246
RAX: ffffa17d4eb7fa80 RBX: ffffa17d40e0aa80 RCX: 00000000000014c0
RDX: 0000000000001a40 RSI: ffffa17d40e0b000 RDI: ffffa17d4eb80000
RBP: ffffa17d40167e20 R08: 0000000000000000 R09: ffff89522ecff8c0
R10: ffffa17d4e4c5000 R11: 0000000000000000 R12: ffffa17d4eb7fa80
R13: 0000000000001a40 R14: 000000000000041a R15: ffffa17d40167e30
FS: 0000000000000000(0000) GS:ffff895257380000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffa17d40e0b000 CR3: 00000001eaeca006 CR4: 00000000001706e0
Call Trace:
<TASK>
? drm_fbdev_generic_helper_fb_dirty+0x207/0x330 [drm_kms_helper]
drm_fb_helper_damage_work+0x8f/0x170 [drm_kms_helper]
process_one_work+0x21f/0x430
worker_thread+0x4e/0x3c0
? __pfx_worker_thread+0x10/0x10
kthread+0xf4/0x120
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2c/0x50
</TASK>
CR2: ffffa17d40e0b000
---[ end trace 0000000000000000 ]---
The is because damage rectangles computed by
drm_fb_helper_memory_range_to_clip() function is not guaranteed to be
bound in the screen's active display area. Possible reasons are:
1) Buffers are allocated in the granularity of page size, for mmap system
call support. The shadow screen buffer consumed by fbdev emulation may
also choosed be page size aligned.
2) The DIV_ROUND_UP() used in drm_fb_helper_memory_range_to_clip()
will introduce off-by-one error.
For example, on a 16KB page size system, in order to store a 1920x1080
XRGB framebuffer, we need allocate 507 pages. Unfortunately, the size
1920*1080*4 can not be divided exactly by 16KB.
1920 * 1080 * 4 = 8294400 bytes
506 * 16 * 1024 = 8290304 bytes
507 * 16 * 1024 = 8306688 bytes
line_length = 1920*4 = 7680 bytes
507 * 16 * 1024 / 7680 = 1081.6
off / line_length = 507 * 16 * 1024 / 7680 = 1081
DIV_ROUND_UP(507 * 16 * 1024, 7680) will yeild 1082
memcpy_toio() typically issue the copy line by line, when copy the last
line, out-of-bound access will be happen. Because:
1082 * line_length = 1082 * 7680 = 8309760, and 8309760 > 8306688
Note that userspace may still write to the invisiable area if a larger
buffer than width x stride is exposed. But it is not a big issue as
long as there still have memory resolve the access if not drafting so
far.
- Also limit the y1 (Daniel)
- keep fix patch it to minimal (Daniel)
- screen_size is page size aligned because of it need mmap (Thomas)
- Adding fixes tag (Thomas)
Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
Fixes: aa15c677cc ("drm/fb-helper: Fix vertical damage clipping")
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/dri-devel/ad44df29-3241-0d9e-e708-b0338bf3c623@189.cn/
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230420030500.1578756-1-suijingfeng@loongson.cn
Define more of the PSR mask bits, and describe in detail
what some of them do. Even if we don't set them all from
the driver they can be very useful during PSR debugging.
Having to trawl through bspec every time to find them is
not fun, and re-reverse engineering the behaviour every
time is time consuming (even if a bit more fun than spec
trawling).
v2: Moar bits
Put the description into a comment to be easily available
v2: Fix the BDW_UNMASK_VBL_TO_REGS_IN_SRD/HSW_UNMASK_VBL_TO_REGS_IN_SRD
description
Rebase due to intel_psr_regs.h
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230411191429.29895-6-ville.syrjala@linux.intel.com
Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
This bridge doesn't actually implement HPD due to it being way too slow
but instead expects the panel driver to wait enough to assume HPD is
asserted. However some panels (such as the generic 'edp-panel') expect
the bridge to deal with the delay and pass maximum delay to the aux
instead.
In order to support such panels, add a dummy implementation of wait
that would just sleep the maximum delay and assume no failure has
happened.
Signed-off-by: Nikita Travkin <nikita@trvn.ru>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230408082014.235425-1-nikita@trvn.ru
Currently, drm_gem_fb_create() doesn't check if the pixel format is
supported, which can lead to the acceptance of invalid pixel formats
e.g. the acceptance of invalid modifiers. Therefore, add a check for
valid formats on drm_gem_fb_create().
Note that this check is only valid for atomic drivers, because, for
non-atomic drivers, checking drm_any_plane_has_format() is not
possible since the format list for the primary plane is fake, and we'd
therefore reject valid formats.
Adding this check to drm_gem_fb_create() will guarantee that the
igt@kms_addfb_basic@addfb25-bad-modifier IGT test passes for drivers
using this callback.
This commit is a recapture of a series sent a while ago. Initially,
I sent a patch [1] similar to this one in which I introduced the
format check to drm_gem_fb_create().
Based on the feedback on the patch, I placed the check inside
framebuffer_check() [2] so that it wouldn't be needed to hit any
driver-specific code path when the check fails. Therefore, we could
remove the check from the specific drivers (i915, amdgpu, and vmwgfx).
But, with some new feedback, it was shown that introducing this check
inside framebuffer_check() is problematic for the i915 driver [3].
For the i915 driver, in the legacy case, in which we don't get the
modifier from the userspace, i915's fb_create hook computes the right
modifier, which isn't necessarily linear. Therefore, if we check the
modifier before that point, we might get wrong answers.
So, I kept the check inside the i915 driver and removed the check from
amdgpu and vmwgfx [4]. But, this yet hasn't solved the i915 problem [5].
As we cannot add the check inside framebuffer_check() without
affecting the i915 behavior, this commit went back to the original
patch. This way we can guarantee a more uniform behavior from the
drivers that use the drm_gem_fb_create() callback.
[1] https://lore.kernel.org/dri-devel/20230103125322.855089-1-mcanal@igalia.com/T/
[2] https://lore.kernel.org/dri-devel/20230109105807.18172-1-mcanal@igalia.com/T/
[3] https://lore.kernel.org/dri-devel/Y8AAdW2y7zN7DCUZ@intel.com/
[4] https://lore.kernel.org/dri-devel/20230113112743.188486-1-mcanal@igalia.com/T/
[5] https://lore.kernel.org/dri-devel/Y8FXWvEhO7GCRKVJ@intel.com/
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230412142923.136707-1-mcanal@igalia.com
Although ADL-P and DG2 both use the same general power well setup, the
DC5/DC6 requirements are slightly different which means each platform
should have its own "DC off" power well.
DG2 (i.e., Xe_HPD IP) requires that DC5 be disabled whenever PG2 is
active. However ADL-P (i.e., Xe_LPD IP) only requires DC5/DC6 to be
disabled when the PGC or PGD subwells are active; we should be able to
remain in these DC states when PGB and general PG2 functionality is in
use.
v2: Use dc_of as power well name.
Move xehpd power domain definitions near power well definition.(Imre)
Bspec: 49193
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230418220446.2205509-2-radhakrishna.sripada@intel.com
It already happend a few times that patches slipped through which
implemented access to an entity through a job that was already removed
from the entities queue. Since jobs and entities might have different
lifecycles, this can potentially cause UAF bugs.
In order to make it obvious that a jobs entity pointer shouldn't be
accessed after drm_sched_entity_pop_job() was called successfully, set
the jobs entity pointer to NULL once the job is removed from the entity
queue.
Moreover, debugging a potential NULL pointer dereference is way easier
than potentially corrupted memory through a UAF.
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Link: https://lore.kernel.org/r/20230418100453.4433-1-dakr@redhat.com
Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
Signed-off-by: Luben Tuikov <luben.tuikov@amd.com>
[Why]
1. It could hit bandwidth limitdation under single dimm
memory when connecting 8K external monitor.
2. IsSupportedVidPn got validation failed with
2K240Hz eDP + 8K24Hz external monitor.
3. It's better to filter out such combination in
EnumVidPnCofuncModality
4. For short term, filter out in dc bandwidth validation.
[How]
Force 2K@240Hz+8K@24Hz timing validation false in dc.
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Daniel Miess <Daniel.Miess@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
[Why]
After gpu-reset, sometimes the driver fails to enable vblank irq,
causing flip_done timed out and the desktop freezed.
During gpu-reset, we disable and enable vblank irq in dm_suspend() and
dm_resume(). Later on in amdgpu_irq_gpu_reset_resume_helper(), we check
irqs' refcount and decide to enable or disable the irqs again.
However, we have 2 sets of API for controling vblank irq, one is
dm_vblank_get/put() and another is amdgpu_irq_get/put(). Each API has
its own refcount and flag to store the state of vblank irq, and they
are not synchronized.
In drm we use the first API to control vblank irq but in
amdgpu_irq_gpu_reset_resume_helper() we use the second set of API.
The failure happens when vblank irq was enabled by dm_vblank_get()
before gpu-reset, we have vblank->enabled true. However, during
gpu-reset, in amdgpu_irq_gpu_reset_resume_helper() vblank irq's state
checked from amdgpu_irq_update() is DISABLED. So finally it disables
vblank irq again. After gpu-reset, if there is a cursor plane commit,
the driver will try to enable vblank irq by calling drm_vblank_enable(),
but the vblank->enabled is still true, so it fails to turn on vblank
irq and causes flip_done can't be completed in vblank irq handler and
desktop become freezed.
[How]
Combining the 2 vblank control APIs by letting drm's API finally calls
amdgpu_irq's API, so the irq's refcount and state of both APIs can be
synchronized. Also add a check to prevent refcount from being less then
0 in amdgpu_irq_put().
v2:
- Add warning in amdgpu_irq_enable() if the irq is already disabled.
- Call dc_interrupt_set() in dm_set_vblank() to avoid refcount change
if it is in gpu-reset.
v3:
- Improve commit message and code comments.
Signed-off-by: Alan Liu <HaoPing.Liu@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
v1: To support multple XCD case (Le)
v2: unify naming style (Le)
v3: apply the changes to gc v11_0 (Hawking)
v4: apply the changes to gc SOC21 (Morris)
Signed-off-by: Le Ma <le.ma@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Morris Zhang <Shiwu.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Change those v9_4_3 interfaces which are exposed in gfx_v9_0.c.
For some active single-xcc emu models, the code path in
gfx_v9_0.c is better to keep reserved for a while.
Signed-off-by: Le Ma <le.ma@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>