# CVE-2025-21956: drm/amd/display: Assign normalized\_pix\_clk when color depth = 14

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2025-04-01 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 4.15

## Description

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Assign normalized_pix_clk when color depth = 14 [WHY & HOW] A warning message "WARNING: CPU: 4 PID: 459 at ... /dc_resource.c:3397 calculate_phy_pix_clks+0xef/0x100 [amdgpu]" occurs because the display_color_depth == COLOR_DEPTH_141414 is not handled. This is observed in Radeon RX 6600 XT. It is fixed by assigning pix_clk * (14 * 3) / 24 - same as the rests. Also fixes the indentation in get_norm_pix_clk. (cherry picked from commit 274a87eb389f58eddcbc5659ab0b180b37e92775)

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
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## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/cca3ab74f90176099b6392e8e894b52b27b3d080
- https://git.kernel.org/stable/c/0174a2e5770efee9dbd4b58963ed4d939298ff5e
- https://git.kernel.org/stable/c/0c0016712e5dc23ce4a7e673cbebc24a535d8c8a
- https://git.kernel.org/stable/c/dc831b38680c47d07e425871a9852109183895cf
- https://git.kernel.org/stable/c/a8f77e1658d78e4a8bb227a83bcee67de97f7634
- https://git.kernel.org/stable/c/04f90b505ad3a6eed474bbaa03167095fef5203a
- https://git.kernel.org/stable/c/27df30106690969f7d63604f0d49ed8e9bffa2cb
- https://git.kernel.org/stable/c/79e31396fdd7037c503e6add15af7cb00633ea92

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Page: https://cve.now/CVE-2025-21956
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