Bug 2536333 (CVE-2026-90286)

Summary: CVE-2026-90286 kernel: drm/amdgpu/gfx6: Use PFP on the compute queues too
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's AMD GPU (Graphics Processing Unit) driver, specifically affecting GFX6 series GPUs. This vulnerability stems from incorrect handling of the Pre-Fetch Parser (PFP) on compute queues, which can lead to synchronization issues. An attacker could potentially exploit this flaw to cause system instability or a denial of service by triggering race conditions during pipeline synchronization or incorrect state after a virtual machine (VM) flush.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-17 17:24:59 UTC 
In the Linux kernel, the following vulnerability has been resolved:

drm/amdgpu/gfx6: Use PFP on the compute queues too

On GFX6, the compute rings use the same CP path as
the graphics ring. The only difference is that they
don't support draw commands. (As opposed to GFX7 and
newer which have a separate command parser that is
called MEC for compute queues.)

This means that we have to take into consideration
that the PFP also exists on compute queues on GFX6:

Use PFP for register writes on both graphics and
compute queues.

In the pipeline sync, use the PFP to wait for the
previous fence (and not the ME) to prevent the PFP
from starting to execute the next submission while
the ME is still in the previous submission.

After a VM flush, emit PFP_SYNC_ME on compute
queues as well.
Comment 1 gkamathe 2026-09-22 17:57:56 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90286.mbox