On 18/11/2024 09:52, Melissa Wen wrote:
On 14/11/2024 16:04, Mario Limonciello wrote:
Although it's really useful information for AMD people, the Jira
shouldn't be in the "title" of the commit message.
"If" we want to get into the habit of including this information for
display code we should come up with a prescriptive field that goes
into the commit message during promotion and it should be part of all
patches in the promotion that have it.
Something like this:
AMD-Jira: SWDEV-476969
Probably need to align that with other stakeholders though before
starting that way.
On 11/14/2024 08:37, Zaeem Mohamed wrote:
[why]
Prevent index-out-of-bounds due to requiring cursor overlay when
plane_count is MAX_SURFACES.
[how]
Bounds check on plane_count when requiring overlay cursor.
Any link to failing bugs or anything like that you can include?
Hi Mario,
About this question, these are the related issues:
- Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3693
- Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3594
You can find more details in previous iterations related to this bug:
-
https://lore.kernel.org/amd-gfx/575d66c7-e77d-42ea-acbf-412d6e508a0b@xxxxxxxxxx/
-
https://lore.kernel.org/amd-gfx/20240925154324.348774-1-mwen@xxxxxxxxxx/
Co-developed-by: Melissa Wen <mwen@xxxxxxxxxx>
Signed-off-by: Zaeem Mohamed <zaeem.mohamed@xxxxxxx>
You're missing Melisaa's SoB for a co-developed patch.
IIRC this should fail checkpatch.
I already mentioned before, I don't think I actually co-dev this code,
so Zaeem can remove it in the next iteration.
---
BTW, about the implementation:
As I don't have the proper environment, I asked reporters to check
this patch up and it doesn't help prevent interface freeze.
It seems to prevent the out of bounds bug but is causing a page fault
now:
kernel: BUG: unable to handle page fault for address: 000000000174e354
From their feedback, I found curious that MAX_SURFACES -> 4 prevents
the freeze but not completely solve the problem.
MAX_SURFACES -> 6 solves it, what let me consider that the
MAX_SURFACES vs MAX_SURFACE_NUM vs MAX_PLANE mismatch might be related.
I'm going to analyzing the logs but you can find more details here:
https://gitlab.freedesktop.org/drm/amd/-/issues/3693#note_2658994
Hi Zaeem,
I managed to reproduce the interface freeze on kernel v6.11.4 (Fedora
41) and
amd-staging-drm-next and I have some findings to share that might be
relevant.
- I'm running Fedora 41 or Pop!_OS 22.04 with Cosmic on DCN301. The
issue was
also reported on DCN312 and DCN314.
- Steps to reproduce the interface freeze:
1. Start a Cosmic session.
2. Open firefox and drag to the right half of the desktop (multitask
resizing).
3. Open file manager and drag to the top-left quarter of the desktop.
<- Here the interface freezes.
- Running v6.11.4 kernel (Fedora), we can see a bunch of
array-index-out-of-bounds error on the dmesg, but the last error is
actually
the page-fault error reported by one user. Which means, the
page-fault isn't
related to Zaeem's patch.
- dmesg:
https://gitlab.freedesktop.org/-/project/4522/uploads/619a13e78cc5e9a645fb208ddff592b1/index-out-of-bounds-plus-page-fault-fedora41-cosmic-6-11-kernel.txt
- Running amd-staging-drm-next kernel, there is only the page-fault
error, and
no array-index-out-of-bounds. So the page-fault is the main issue
since the
beginning.
- dmesg:
https://gitlab.freedesktop.org/-/project/4522/uploads/f17b85e66f0a8c7e98013ad3b6f174f8/page-fault-fedora41-cosmic-asdn-kernel.txt
The stack trace of the page fault error [1] points to
commit_minimal_transition_state machinery, so I suspect the mismatch between
MAX_SURFACE and MAX_SURFACE_NUM may be related.
I'm investigating the problem and adding more info to the AMD issue:
- https://gitlab.freedesktop.org/drm/amd/-/issues/3693#note_2675384
[1]
[Nov26 21:33] BUG: unable to handle page fault for address: 0000000051d0f08b
[ +0.000015] #PF: supervisor read access in kernel mode
[ +0.000006] #PF: error_code(0x0000) - not-present page
[ +0.000005] PGD 0 P4D 0
[ +0.000007] Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
[ +0.000006] CPU: 4 PID: 71 Comm: kworker/u32:6 Not tainted 6.10.0+ #300
[ +0.000006] Hardware name: Valve Jupiter/Jupiter, BIOS F7A0131 01/30/2024
[ +0.000007] Workqueue: events_unbound commit_work [drm_kms_helper]
[ +0.000040] RIP: 0010:copy_stream_update_to_stream.isra.0+0x30d/0x750
[amdgpu]
[ +0.000847] Code: 8b 10 49 89 94 24 f8 00 00 00 48 8b 50 08 49 89 94
24 00 01 00 00 8b 40 10 41 89 84 24 08 01 00 00 49 8b 45 78 48 85 c0 74
0b <0f> b6 00 41 88 84 24 90 64 00 00 49 8b 45 60 48 85 c0 74 3b 48 8b
[ +0.000010] RSP: 0018:ffffc203802f79a0 EFLAGS: 00010206
[ +0.000009] RAX: 0000000051d0f08b RBX: 0000000000000004 RCX:
ffff9f964f0a8070
[ +0.000004] RDX: ffff9f9710f90e40 RSI: ffff9f96600c8000 RDI:
ffff9f964f000000
[ +0.000004] RBP: ffffc203802f79f8 R08: 0000000000000000 R09:
0000000000000000
[ +0.000005] R10: 0000000000000000 R11: 0000000000000000 R12:
ffff9f96600c8000
[ +0.000004] R13: ffff9f9710f90e40 R14: ffff9f964f000000 R15:
ffff9f96600c8000
[ +0.000004] FS: 0000000000000000(0000) GS:ffff9f9970000000(0000)
knlGS:0000000000000000
[ +0.000005] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ +0.000005] CR2: 0000000051d0f08b CR3: 00000002e6a20000 CR4:
0000000000350ef0
[ +0.000005] Call Trace:
[ +0.000011] <TASK>
[ +0.000010] ? __die_body.cold+0x19/0x27
[ +0.000012] ? page_fault_oops+0x15a/0x2d0
[ +0.000014] ? exc_page_fault+0x7e/0x180
[ +0.000009] ? asm_exc_page_fault+0x26/0x30
[ +0.000013] ? copy_stream_update_to_stream.isra.0+0x30d/0x750 [amdgpu]
[ +0.000739] ? dc_commit_state_no_check+0xd6c/0xe70 [amdgpu]
[ +0.000470] update_planes_and_stream_state+0x49b/0x4f0 [amdgpu]
[ +0.000450] ? srso_return_thunk+0x5/0x5f
[ +0.000009] ? commit_minimal_transition_state+0x239/0x3d0 [amdgpu]
[ +0.000446] update_planes_and_stream_v2+0x24a/0x590 [amdgpu]
[ +0.000464] ? srso_return_thunk+0x5/0x5f
[ +0.000009] ? sort+0x31/0x50
[ +0.000007] ? amdgpu_dm_atomic_commit_tail+0x159f/0x3a30 [amdgpu]
[ +0.000508] ? srso_return_thunk+0x5/0x5f
[ +0.000009] ? amdgpu_crtc_get_scanout_position+0x28/0x40 [amdgpu]
[ +0.000377] ? srso_return_thunk+0x5/0x5f
[ +0.000009] ?
drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x160/0x390 [drm]
[ +0.000058] ? srso_return_thunk+0x5/0x5f
[ +0.000005] ? dma_fence_default_wait+0x8c/0x260
[ +0.000010] ? srso_return_thunk+0x5/0x5f
[ +0.000005] ? wait_for_completion_timeout+0x13b/0x170
[ +0.000006] ? srso_return_thunk+0x5/0x5f
[ +0.000005] ? dma_fence_wait_timeout+0x108/0x140
[ +0.000010] ? commit_tail+0x94/0x130 [drm_kms_helper]
[ +0.000024] ? process_one_work+0x177/0x330
[ +0.000008] ? worker_thread+0x266/0x3a0
[ +0.000006] ? __pfx_worker_thread+0x10/0x10
[ +0.000004] ? kthread+0xd2/0x100
[ +0.000006] ? __pfx_kthread+0x10/0x10
[ +0.000006] ? ret_from_fork+0x34/0x50
[ +0.000004] ? __pfx_kthread+0x10/0x10
[ +0.000005] ? ret_from_fork_asm+0x1a/0x30
[ +0.000011] </TASK>
BR,
Melissa Wen
---
amdgpu_dm/amdgpu_dm.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/amdgpu_dm/amdgpu_dm.c b/amdgpu_dm/amdgpu_dm.c
index 97e0a1bbba..964497c613 100644
--- a/amdgpu_dm/amdgpu_dm.c
+++ b/amdgpu_dm/amdgpu_dm.c
@@ -11821,8 +11821,16 @@ static int amdgpu_dm_atomic_check(struct
drm_device *dev,
/* Overlay cusor not subject to native cursor
restrictions */
dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
- if (dm_new_crtc_state->cursor_mode == DM_CURSOR_OVERLAY_MODE)
+ if (dm_new_crtc_state->cursor_mode ==
DM_CURSOR_OVERLAY_MODE) {
+ if (dc->current_state->stream_status->plane_count >
MAX_SURFACES) {
+ drm_dbg_driver(crtc->dev,
+ "Can't enable cursor plane with %d
planes\n", MAX_SURFACES);
+ ret = -EINVAL;
+ goto fail;
+ }
+
continue;
+ }
/* Check if rotation or scaling is enabled on DCN401 */
if ((drm_plane_mask(crtc->cursor) &
new_crtc_state->plane_mask) &&
