Bug 2468106 (CVE-2026-43294)

Summary: CVE-2026-43294 kernel: drm: renesas: rz-du: mipi_dsi: fix kernel panic when rebooting for some panels
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
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Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's MIPI-DSI driver. When a system with certain display panels is rebooted, the MIPI-DSI interface may stop prematurely. This can lead to a kernel panic, causing the system to crash and resulting in a Denial of Service (DoS).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-05-08 14:04:51 UTC
In the Linux kernel, the following vulnerability has been resolved:

drm: renesas: rz-du: mipi_dsi: fix kernel panic when rebooting for some panels

Since commit 56de5e305d4b ("clk: renesas: r9a07g044: Add MSTOP for RZ/G2L")
we may get the following kernel panic, for some panels, when rebooting:

  systemd-shutdown[1]: Rebooting.
  Call trace:
   ...
   do_serror+0x28/0x68
   el1h_64_error_handler+0x34/0x50
   el1h_64_error+0x6c/0x70
   rzg2l_mipi_dsi_host_transfer+0x114/0x458 (P)
   mipi_dsi_device_transfer+0x44/0x58
   mipi_dsi_dcs_set_display_off_multi+0x9c/0xc4
   ili9881c_unprepare+0x38/0x88
   drm_panel_unprepare+0xbc/0x108

This happens for panels that need to send MIPI-DSI commands in their
unprepare() callback. Since the MIPI-DSI interface is stopped at that
point, rzg2l_mipi_dsi_host_transfer() triggers the kernel panic.

Fix by moving rzg2l_mipi_dsi_stop() to new callback function
rzg2l_mipi_dsi_atomic_post_disable().

With this change we now have the correct power-down/stop sequence:

  systemd-shutdown[1]: Rebooting.
  rzg2l-mipi-dsi 10850000.dsi: rzg2l_mipi_dsi_atomic_disable(): entry
  ili9881c-dsi 10850000.dsi.0: ili9881c_unprepare(): entry
  rzg2l-mipi-dsi 10850000.dsi: rzg2l_mipi_dsi_atomic_post_disable(): entry
  reboot: Restarting system