Re: [PATCH v5 12/12] mm: change the contract for free_pgtables(), update docs

From: "David Hildenbrand (Arm)" <david@kernel.org>
To: "Lorenzo Stoakes (ARM)" <ljs@kernel.org>,
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Subject: Re: [PATCH v5 12/12] mm: change the contract for free_pgtables(), update docs
Date: Mon, 28 Sep 2026 14:06:22 +0200	[thread overview]
Message-ID: <232ea2c2-a594-4a31-8ec8-7884707f1bc9@kernel.org> (raw)
In-Reply-To: <20260925-rcu-pagetable-freeing-v5-12-31e91065fea4@kernel.org>

On 9/25/26 22:09, Lorenzo Stoakes (ARM) wrote:
> Now that page tables are freed after an RCU grace period, it is safe for
> read-only page table walkers to walk page table ranges that are being
> concurrently torn down, provided the mm is kept alive via mmgrab().
> 
> It is however unsafe for writers to do so, as they must obtain an
> appropriate lock to do so safely.
> 
> Update the pte_offset_map_lock()'s comment block to reflect this.
> 
> Similarly update the process addresses documentation.
> 
> Acked-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
> Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
> ---

Acked-by: David Hildenbrand (Arm) <david@kernel.org>

-- 
Cheers,

David