CVE - CVE-2024-46839

CVE-ID
CVE-2024-46839	Learn more at National Vulnerability Database (NVD) • CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
Description
In the Linux kernel, the following vulnerability has been resolved: workqueue: Improve scalability of workqueue watchdog touch On a ~2000 CPU powerpc system, hard lockups have been observed in the workqueue code when stop_machine runs (in this case due to CPU hotplug). This is due to lots of CPUs spinning in multi_cpu_stop, calling touch_nmi_watchdog() which ends up calling wq_watchdog_touch(). wq_watchdog_touch() writes to the global variable wq_watchdog_touched, and that can find itself in the same cacheline as other important workqueue data, which slows down operations to the point of lockups. In the case of the following abridged trace, worker_pool_idr was in the hot line, causing the lockups to always appear at idr_find. watchdog: CPU 1125 self-detected hard LOCKUP @ idr_find Call Trace: get_work_pool __queue_work call_timer_fn run_timer_softirq __do_softirq do_softirq_own_stack irq_exit timer_interrupt decrementer_common_virt * interrupt: 900 (timer) at multi_cpu_stop multi_cpu_stop cpu_stopper_thread smpboot_thread_fn kthread Fix this by having wq_watchdog_touch() only write to the line if the last time a touch was recorded exceeds 1/4 of the watchdog threshold.
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
MISC:https://git.kernel.org/stable/c/241bce1c757d0587721512296952e6bba69631ed URL:https://git.kernel.org/stable/c/241bce1c757d0587721512296952e6bba69631ed MISC:https://git.kernel.org/stable/c/98f887f820c993e05a12e8aa816c80b8661d4c87 URL:https://git.kernel.org/stable/c/98f887f820c993e05a12e8aa816c80b8661d4c87 MISC:https://git.kernel.org/stable/c/9d08fce64dd77f42e2361a4818dbc4b50f3c7dad URL:https://git.kernel.org/stable/c/9d08fce64dd77f42e2361a4818dbc4b50f3c7dad MISC:https://git.kernel.org/stable/c/a2abd35e7dc55bf9ed01e2b3481fa78e086d3bf4 URL:https://git.kernel.org/stable/c/a2abd35e7dc55bf9ed01e2b3481fa78e086d3bf4 MISC:https://git.kernel.org/stable/c/da5f374103a1e0881bbd35847dc57b04ac155eb0 URL:https://git.kernel.org/stable/c/da5f374103a1e0881bbd35847dc57b04ac155eb0
Assigning CNA
kernel.org
Date Record Created
20240911	Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20240911)
Votes (Legacy)

Comments (Legacy)

Proposed (Legacy)
N/A
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