linux-kernel - [PATCH 0/1] mm/page_alloc: dynamic min_free

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <tencent_C5AD9528AAB1853E24A7DC98A19D700E3808@qq.com>
Date: Sun,  4 Jan 2026 20:23:22 +0800
From: wujing <realwujing@...com>
To: Andrew Morton <akpm@...ux-foundation.org>,
	Vlastimil Babka <vbabka@...e.cz>
Cc: Suren Baghdasaryan <surenb@...gle.com>,
	Michal Hocko <mhocko@...e.com>,
	Brendan Jackman <jackmanb@...gle.com>,
	Johannes Weiner <hannes@...xchg.org>,
	Zi Yan <ziy@...dia.com>,
	linux-mm@...ck.org,
	linux-kernel@...r.kernel.org,
	Qiliang Yuan <yuanql9@...natelecom.cn>,
	wujing <realwujing@...com>
Subject: [PATCH 0/1] mm/page_alloc: dynamic min_free_kbytes adjustment

Atomic allocations (GFP_ATOMIC), particularly in network interrupt contexts,
are prone to failure during bursts of traffic if the pre-configured 
min_free_kbytes (atomic reserve) is insufficient. These failures lead to 
packet drops and performance degradation.

Static tuning of vm.min_free_kbytes is often challenging: setting it too 
low risks drops, while setting it too high wastes valuable memory.

This patch series introduces a reactive mechanism that:
1. Detects critical order-0 GFP_ATOMIC allocation failures.
2. Automatically doubles vm.min_free_kbytes to reserve more memory for 
   future bursts.
3. Enforces a safety cap (1% of total RAM) to prevent OOM or excessive waste.

This allows the system to self-adjust to the workload's specific atomic 
memory requirements without manual intervention.

wujing (1):
  mm/page_alloc: auto-tune min_free_kbytes on atomic allocation failure

 mm/page_alloc.c | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

-- 
2.39.5