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x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: EB5EE180002 X-Stat-Signature: cjrdstezk9xdhigckofqwz3ptinmo9dh X-HE-Tag: 1788650489-855940 X-HE-Meta: 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 5W+xJJO/ QHsNdnRwFxP2Z5yBQw0WfHfP8JTkV238cYYzhNw0tWzIBOw5oM4Lz17v8CsVyQh9N5WfKrpGXL8mAUqg3zq/TdDjrHCh3O/BxWQZIfM2jd4Vl+eTYJfHFkhEbqeXt+/Y4l3XBD3ky7nDWJpODk7KoylZnHKNfazMrIoG1fmol/vX69ywb/+vONrkQyAs47T0CDnUm2g+xW2lned1JysrYhXVckN/K6jJ14422n4Iojao8esYbcdyeXwh2hNMKAgYNFIqeVwahyR95JhHVxC5nXlA+iuxQmfoZBi2WK/DXcceUedxD3lf3oQalCxYGJ6hDnzheBpAWjW6qho6uI2HWTJ9lCrhmy9ZFBY+TZHJOYYZ2Hk4IpWg3xwuJi2qbylyyvlW4avmLS+elvQmZySqX86JMrNmA1RNfl//bV8xfYAha5co= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sat, 5 Sep 2026 14:18:19 +0800 Jinjiang Tu wrote: > On arm64 server, we found __anon_vma_prepare() reuses anon_vma and > anon_vma->root is stale due to missing memory barrier, leading to > lock and unlock two different anon_vma->root, thus leading to a anon_vma > will never be unlocked, and another anon_vma couldn't be locked anymore. > > The race is as follows: > > ... > > Without this fix, our production environment could reproduce this issue > about 2-5 times each month. That's important info. Can you tell us more? How was this observed by operations people? A copy-n-paste of the kernel messages would be helpful. This will help downstream people to decide whether this patch fixes a thing they're seeing happen.