Re: [PATCH 11/12] mm: make userland page table freeing RCU-safe

From: Kiryl Shutsemau <kas@kernel.org>
To: "Lorenzo Stoakes (ARM)" <ljs@kernel.org>
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Subject: Re: [PATCH 11/12] mm: make userland page table freeing RCU-safe
Date: Tue, 1 Sep 2026 14:33:14 +0100	[thread overview]
Message-ID: <apbSaL0YaQqtO9XB@thinkstation> (raw)
In-Reply-To: <20260901-rcu-pagetable-freeing-v1-11-5456a81c8212@kernel.org>

On Tue, Sep 01, 2026 at 12:01:31PM +0100, Lorenzo Stoakes (ARM) wrote:
> With this change in place the kernel policy is now that all page tables are

s/all/userspace/ as subject implies?

BTW, what is your take on kernel page tables? Do we want the same policy
there. pagetable_free_kernel() is not RCU-safe as it is.

> freed after an RCU grace period, and thus it is now safe to unconditionally
> perform page table walks under RCU, safe in the knowledge that page tables
> will not be freed underneath the walker.

-- 
  Kiryl Shutsemau / Kirill A. Shutemov

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