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	Sat, 29 Nov 2025 03:55:10 +0000
Date: Sat, 29 Nov 2025 03:55:10 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Zizhi Wo <wozizhi@huaweicloud.com>
Cc: Will Deacon <will@kernel.org>,
	Linus Torvalds <torvalds@linux-foundation.org>, jack@suse.com,
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	wangkefeng.wang@huawei.com, pangliyuan1@huawei.com,
	xieyuanbin1@huawei.com
Subject: Re: [Bug report] hash_name() may cross page boundary and trigger
 sleep in RCU context
Message-ID: <20251129035510.GI3538@ZenIV>
References: <20251126090505.3057219-1-wozizhi@huaweicloud.com>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Sat, Nov 29, 2025 at 09:02:27AM +0800, Zizhi Wo wrote:

> Thank you very much for the answer. For the vmalloc area, I checked the
> call points on the vfs side, such as dentry_string_cmp() or hash_name().
> Their "names addr" are all assigned by kmalloc(), so there should be no
> corresponding issues. But I'm not familiar with the other calling
> points...

Pathname might be a symlink body, sitting in page cache or whatever
->get_link() has returned...