{"id":"CVE-2026-80611","title":"ACPI: processor_idle: Mark LPI enter functions as __cpuidle","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nACPI: processor_idle: Mark LPI enter functions as __cpuidle\n\nWhen function tracing or Kprobes is enabled, entering an ACPI Low\nPower Idle (LPI) state triggers the follo…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= a36a7fecfe6071732075ad5aa31196adce13181b < c17fe25dcb55ab94f6aa2930b7504ea666d5fcc2","Linux >= a36a7fecfe6071732075ad5aa31196adce13181b < 10f675902a5fc88ccfe34bb8aa37de50806b03b1","Linux >= a36a7fecfe6071732075ad5aa31196adce13181b < 5b6165d7ec38477e8cfa41bfa464959957953822","Linux >= a36a7fecfe6071732075ad5aa31196adce13181b < 8bbe4dd7964552f74c271c3a8d95a4331a8ab5f9","Linux >= a36a7fecfe6071732075ad5aa31196adce13181b < 956ca5d72c76504824c8eb601879da9476973e15","Linux 4.8"],"published":"2026-08-28","updated":"2026-10-21","sourceUpdated":"2026-10-21T12:46:33.836Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-80611","references":[{"url":"https://git.kernel.org/stable/c/c17fe25dcb55ab94f6aa2930b7504ea666d5fcc2"},{"url":"https://git.kernel.org/stable/c/10f675902a5fc88ccfe34bb8aa37de50806b03b1"},{"url":"https://git.kernel.org/stable/c/5b6165d7ec38477e8cfa41bfa464959957953822"},{"url":"https://git.kernel.org/stable/c/8bbe4dd7964552f74c271c3a8d95a4331a8ab5f9"},{"url":"https://git.kernel.org/stable/c/956ca5d72c76504824c8eb601879da9476973e15"}],"tags":["cve.org"],"epss":0.00209,"epssPercentile":0.10416,"ingestedAt":"2026-10-21T12:48:53.571Z","slug":"CVE-2026-80611","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nACPI: processor_idle: Mark LPI enter functions as __cpuidle\n\nWhen function tracing or Kprobes is enabled, entering an ACPI Low\nPower Idle (LPI) state triggers the following RCU splat:\n\n  RCU not on for: acpi_idle_lpi_enter+0x4/0xd8\n  WARNING: CPU: 8 PID: 0 at include/linux/trace_recursion.h:162 function_trace_call+0x1e8/0x228\n\nThe acpi_idle_lpi_enter() function is invoked within the cpuidle\npath after RCU has already been disabled for the current local CPU.\nConsequently, ftrace's function_trace_call() expects RCU to be\nactively watching before recording trace data, emitting a warning\nif it is not.\n\nFix this by annotating acpi_idle_lpi_enter(), the generic __weak\nstub, and the RISC-V implementation of acpi_processor_ffh_lpi_enter()\nwith __cpuidle. This moves these functions into the '.cpuidle.text'\nsection, implicitly disabling ftrace instrumentation (notrace) along\nthis sensitive path and preventing trace-induced RCU warnings during\nidle entry.\n\n## Affected\n\n- `Linux >= a36a7fecfe6071732075ad5aa31196adce13181b < c17fe25dcb55ab94f6aa2930b7504ea666d5fcc2`\n- `Linux >= a36a7fecfe6071732075ad5aa31196adce13181b < 10f675902a5fc88ccfe34bb8aa37de50806b03b1`\n- `Linux >= a36a7fecfe6071732075ad5aa31196adce13181b < 5b6165d7ec38477e8cfa41bfa464959957953822`\n- `Linux >= a36a7fecfe6071732075ad5aa31196adce13181b < 8bbe4dd7964552f74c271c3a8d95a4331a8ab5f9`\n- `Linux >= a36a7fecfe6071732075ad5aa31196adce13181b < 956ca5d72c76504824c8eb601879da9476973e15`\n- `Linux 4.8`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}