Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: drm/sched: Check scheduler work queue before calling timeout handling During an IGT GPU reset test we see again oops despite of commit 0c8c901aaaebc9 (drm/sched: Check scheduler ready before calling timeout handling). It uses ready condition whether to call drm_sched_fault which unwind the TDR leads to GPU reset. However it looks the ready condition is overloaded with other meanings, for example, for the following stack is related GPU reset : 0 gfx_v9_0_cp_gfx_start 1 gfx_v9_0_cp_gfx_resume 2 gfx_v9_0_cp_resume 3 gfx_v9_0_hw_init 4 gfx_v9_0_resume 5 amdgpu_device_ip_resume_phase2 does the following: /* start the ring */ gfx_v9_0_cp_gfx_start(adev); ring->sched.ready = true; The same approach is for other ASICs as well : gfx_v8_0_cp_gfx_resume gfx_v10_0_kiq_resume, etc... As a result, our GPU reset test causes GPU fault which calls unconditionally gfx_v9_0_fault and then drm_sched_fault. However now it depends on whether the interrupt service routine drm_sched_fault is executed after gfx_v9_0_cp_gfx_start is completed which sets the ready field of the scheduler to true even for uninitialized schedulers and causes oops vs no fault or when ISR drm_sched_fault is completed prior gfx_v9_0_cp_gfx_start and NULL pointer dereference does not occur. Use the field timeout_wq to prevent oops for uninitialized schedulers. The field could be initialized by the work queue of resetting the domain. v1: Corrections to commit message (Luben)
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 11b3b9f461c5c4f700f6c8da202fcc2fd6418e1f before c43a96fc00b662cef1ef0eb22d40441ce2abae8f; affected 11b3b9f461c5c4f700f6c8da202fcc2fd6418e1f before 2da5bffe9eaa5819a868e8eaaa11b3fd0f16a691 |
| Linux / Linux | affected 6.3; unaffected 0 before 6.3; unaffected 6.3.4 through 6.3.*; unaffected 6.4 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/c43a96fc00b662cef1ef0eb22d40441ce2abae8f
- https://git.kernel.org/stable/c/2da5bffe9eaa5819a868e8eaaa11b3fd0f16a691
ADP enrichment
No English description supplied.
No references supplied.