hung task symptoms

Hung task symptoms in Linux often appear as processes stuck in an uninterruptible sleep state for an extended period, resembling a deadlock. A recent example involves CVE-2026-31448 in the ext4 filesystem, where a failure path during mkdir or mknod can cause an infinite loop while holding critical locks. This leads to blocked tasks that exhibit classic hung task symptoms, such as long-running blocked processes and system unresponsiveness. The issue stems from how ext4 handles extent-tree insertion failures, and the fix addresses infinite loops caused by residual data. Understanding these symptoms is crucial for diagnosing filesystem-related hangs in Linux environments.