Answer in brief
CVE-2026-89759 records a Unknown severity vulnerability in mm/kmemleak: avoid soft lockup when scanning task stacks. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=c4b28963fd79457315783b3b0f21c01eb88cfdc1 <9a1b12c06c192290b8479de48f66f1e75d89c4b7 || >=c4b28963fd79457315783b3b0f21c01eb88cfdc1 <3fc8044251de21555fb02c365fa681bab8b0db55 || >=c4b28963fd79457315783b3b0f21c01eb88cfdc1 <1838c704bcb4fd3556cf67513c6f97a39099e35c || >=c4b28963fd79457315783b3b0f21c01eb88cfdc1 <5d10d4e19e6daa487f0cd0ea6cba472325de92f9 | 9a1b12c06c192290b8479de48f66f1e75d89c4b7, 3fc8044251de21555fb02c365fa681bab8b0db55, 1838c704bcb4fd3556cf67513c6f97a39099e35c, 5d10d4e19e6daa487f0cd0ea6cba472325de92f9 |
| Linux/Linuxgeneric | 5.10 | Not reported |
| Linux/Linuxgeneric | >=c4b28963fd79457315783b3b0f21c01eb88cfdc1 <f1cd6c4c35243377882c47236281d03ee3be6eeb || >=c4b28963fd79457315783b3b0f21c01eb88cfdc1 <9a1b12c06c192290b8479de48f66f1e75d89c4b7 || >=c4b28963fd79457315783b3b0f21c01eb88cfdc1 <3fc8044251de21555fb02c365fa681bab8b0db55 || >=c4b28963fd79457315783b3b0f21c01eb88cfdc1 <1838c704bcb4fd3556cf67513c6f97a39099e35c || >=c4b28963fd79457315783b3b0f21c01eb88cfdc1 <5d10d4e19e6daa487f0cd0ea6cba472325de92f9 | f1cd6c4c35243377882c47236281d03ee3be6eeb, 9a1b12c06c192290b8479de48f66f1e75d89c4b7, 3fc8044251de21555fb02c365fa681bab8b0db55, 1838c704bcb4fd3556cf67513c6f97a39099e35c, 5d10d4e19e6daa487f0cd0ea6cba472325de92f9 |
Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 21, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 11, 2026
In the Linux kernel, the following vulnerability has been resolved: mm/kmemleak: avoid soft lockup when scanning task stacks Patch series "mm/kmemleak: avoid soft lockup when scanning task", v3. kmemleak_scan() scans every task stack under one rcu_read_lock() with no reschedule point, which can trip the soft lockup watchdog on hosts with very many threads. That prints the following message, depending on the workload+host configuration: watchdog: BUG: soft lockup - CPU#35 stuck for 22s! [kmemleak:537] scan_block kmemleak_scan kmemleak_scan_thread kthread Patch 1 walks the tasks with find_ge_pid() so the scan reschedules between tasks Patches 2-3 let the scan loops stop early once a scan is interrupted. This patch (of 3): kmemleak_scan() walks every thread and scans its kernel stack under a single rcu_read_lock() with no reschedule point. On a host with very many threads -- amplified by KASAN/lockdep in debug builds -- this loop can hog a CPU long enough to trip the soft lockup watchdog: watchdog: BUG: soft lockup - CPU#35 stuck for 22s! [kmemleak:537] scan_block kmemleak_scan kmemleak_scan_thread kthread A cond_resched() cannot be added directly: the loop runs inside an RCU read-side critical section. Walk the tasks one PID at a time with find_ge_pid(), taking the RCU read lock only to look up and pin each task. The stack is then scanned with no lock held, so cond_resched() runs between tasks and the scan stops early on scan_should_stop(). This follows the next_tgid()/task_seq_get_next() iteration pattern and keeps each RCU critical section short.
Quoted source text, attributed separately from HOL analysis.