CVE ID:	CVE-2024-26937
Description:	In the Linux kernel, the following vulnerability has been resolved: drm/i915/gt: Reset queue_priority_hint on parking Originally, with strict in order execution, we could complete execution only when the queue was empty. Preempt-to-busy allows replacement of an active request that may complete before the preemption is processed by HW. If that happens, the request is retired from the queue, but the queue_priority_hint remains set, preventing direct submission until after the next CS interrupt is processed. This preempt-to-busy race can be triggered by the heartbeat, which will also act as the power- management barrier and upon completion allow us to idle the HW. We may process the completion of the heartbeat, and begin parking the engine before the CS event that restores the queue_priority_hint, causing us to fail the assertion that it is MIN. <3>[ 166.210729] __engine_park:283 GEM_BUG_ON(engine->sched_engine->queue_priority_hint != (-((int)(~0U >> 1)) - 1)) <0>[ 166.210781] Dumping ftrace buffer: <0>[ 166.210795] --------------------------------- ... <0>[ 167.302811] drm_fdin-1097 2..s1. 165741070us : trace_ports: 0000:00:02.0 rcs0: promote { ccid:20 1217:2 prio 0 } <0>[ 167.302861] drm_fdin-1097 2d.s2. 165741072us : execlists_submission_tasklet: 0000:00:02.0 rcs0: preempting last=1217:2, prio=0, hint=2147483646 <0>[ 167.302928] drm_fdin-1097 2d.s2. 165741072us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 1217:2, current 0 <0>[ 167.302992] drm_fdin-1097 2d.s2. 165741073us : __i915_request_submit: 0000:00:02.0 rcs0: fence 3:4660, current 4659 <0>[ 167.303044] drm_fdin-1097 2d.s1. 165741076us : execlists_submission_tasklet: 0000:00:02.0 rcs0: context:3 schedule- in, ccid:40 <0>[ 167.303095] drm_fdin-1097 2d.s1. 165741077us : trace_ports: 0000:00:02.0 rcs0: submit { ccid:40 3:4660* prio 2147483646 } <0>[ 167.303159] kworker/-89 11..... 165741139us : i915_request_retire.part.0: 0000:00:02.0 rcs0: fence c90:2, current 2 <0>[ 167.303208] kworker/-89 11..... 165741148us : __intel_context_do_unpin: 0000:00:02.0 rcs0: context:c90 unpin <0>[ 167.303272] kworker/-89 11..... 165741159us : i915_request_retire.part.0: 0000:00:02.0 rcs0: fence 1217:2, current 2 <0>[ 167.303321] kworker/-89 11..... 165741166us : __intel_context_do_unpin: 0000:00:02.0 rcs0: context:1217 unpin <0>[ 167.303384] kworker/-89 11..... 165741170us : i915_request_retire.part.0: 0000:00:02.0 rcs0: fence 3:4660, current 4660 <0>[ 167.303434] kworker/-89 11d..1. 165741172us : __intel_context_retire: 0000:00:02.0 rcs0: context:1216 retire runtime: { total:56028ns, avg:56028ns } <0>[ 167.303484] kworker/-89 11..... 165741198us : __engine_park: 0000:00:02.0 rcs0: parked <0>[ 167.303534] -0 5d.H3. 165741207us : execlists_irq_handler: 0000:00:02.0 rcs0: semaphore yield: 00000040 <0>[ 167.303583] kworker/-89 11..... 165741397us : __intel_context_retire: 0000:00:02.0 rcs0: context:1217 retire runtime: { total:325575ns, avg:0ns } <0>[ 167.303756] kworker/-89 11..... 165741777us : __intel_context_retire: 0000:00:02.0 rcs0: context:c90 retire runtime: { total:0ns, avg:0ns } <0>[ 167.303806] kworker/-89 11..... 165742017us : __engine_park: __engine_park:283 GEM_BUG_ON(engine->sched_engine->queue_priority_hint != (-((int)(~0U >> 1)) - 1)) <0>[ 167.303811] --------------------------------- <4>[ 167.304722] ------------[ cut here ]------------ <2>[ 167.304725] kernel BUG at drivers/gpu/drm/i915/gt/intel_engine_pm.c:283! <4>[ 167.304731] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI <4>[ 167.304734] CPU: 11 PID: 89 Comm: kworker/11:1 Tainted: G W 6.8.0-rc2-CI_DRM_14193-gc655e0fd2804+ #1 <4>[ 167.304736] Hardware name: Intel Corporation Rocket Lake Client Platform/RocketLake S UDIMM 6L RVP, BIOS RKLSFWI1.R00.3173.A03.2204210138 04/21/2022 <4>[ 167.304738] Workqueue: i915-unordered retire_work_handler [i915] <4>[ 16 ---truncated---
Test IDs:	None available
Cross References:	Common Vulnerability Exposure (CVE) ID: CVE-2024-26937 https://git.kernel.org/stable/c/3b031e4fcb2740988143c303f81f69f18ce86325 https://git.kernel.org/stable/c/3b031e4fcb2740988143c303f81f69f18ce86325 https://git.kernel.org/stable/c/4a3859ea5240365d21f6053ee219bb240d520895 https://git.kernel.org/stable/c/4a3859ea5240365d21f6053ee219bb240d520895 https://git.kernel.org/stable/c/67944e6db656bf1e986aa2a359f866f851091f8a https://git.kernel.org/stable/c/67944e6db656bf1e986aa2a359f866f851091f8a https://git.kernel.org/stable/c/7eab7b021835ae422c38b968d5cc60e99408fb62 https://git.kernel.org/stable/c/7eab7b021835ae422c38b968d5cc60e99408fb62 https://git.kernel.org/stable/c/8fd9b0ce8c26533fe4d5d15ea15bbf7b904b611c https://git.kernel.org/stable/c/8fd9b0ce8c26533fe4d5d15ea15bbf7b904b611c https://git.kernel.org/stable/c/ac9b6b3e8d1237136c8ebf0fa1ce037dd7e2948f https://git.kernel.org/stable/c/ac9b6b3e8d1237136c8ebf0fa1ce037dd7e2948f https://git.kernel.org/stable/c/aed034866a08bb7e6e34d50a5629a4d23fe83703 https://git.kernel.org/stable/c/aed034866a08bb7e6e34d50a5629a4d23fe83703 https://git.kernel.org/stable/c/fe34587acc995e7b1d7a5d3444a0736721ec32b3 https://git.kernel.org/stable/c/fe34587acc995e7b1d7a5d3444a0736721ec32b3