From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D44FC35AC13; Mon, 12 Oct 2026 13:28:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791811737; cv=none; b=FRmNav/cg/9PCiVpCRAQAkOzePza4Rq7IUdkJN+oy2y5ayKXjeLP7bdLjNZXfhnnU8x+ar4JcrPyvDYWUArvrWRshWO6/2GYnOkZ++u9yh7MyoM4LVdHfNRicSHp85ECGzaJIWDQoB5nWn7D3rL/ivZWxb1dukDIWsJz/LpzO0I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791811737; c=relaxed/simple; bh=103ra0tzpz5/P6v7/+KVHh0+Xu6ERlsh3fNFw7jJ7y4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=KJhSLunYblUMHdCb/Y2iQHtNn2PPrOykGbcu6m+yRc8xkNCkqACdFnsgyoZxziJRXDEAkMKW67V1EJiM1bvDC8FaUQOHoNyMLAT0KfSMC28EVXtmhs7ecqsY8xbGHHVderh6U+0MOvuyyCXVS8gvrWXW3rC7rNePyZ31giHHpMA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EC+clTKQ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="EC+clTKQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 693491F0089C; Mon, 12 Oct 2026 13:28:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791811736; bh=BJWJfJvFdRXU7A7CP8bKUhf5LvjKVS564TTBwWUrmqw=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=EC+clTKQWYqPlYBodlVrok9It43/JtduTxKf6oq0WBqsXaEE/fWQ/aLbyuEOxBEBC aj8VV62n48eANgEswgmLe+sz7d3kelzv7I1i9px8FE7JF6AnYtWr2e6QYjbXYTykrD jmHx2nQTevuvQ2BHkjXO4V1TkXJmRZ3fM2oDk5HgpA0u95NXQ5jRnIg30lLZuxf63L LNvVQWM1SN0RxxdCmS2ZYeiECdObn8P2scSsoxqgsYXgnwtoHyEN8DSL5tmogGXL29 PzDDBbn5fGwNRKsY8z0fNjE+OcHXLHepynF1hcpPn8nDR33NkOBgSv72w+94GIr6ZC 26j7dSBXEYR1w== Message-ID: <01371835-cbc6-43f1-9d42-d22bec4ba0c2@kernel.org> Date: Mon, 12 Oct 2026 15:28:50 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/4] riscv/mm: fix hotplug page-table destructor handling To: Muchun Song , Andrew Morton Cc: Oscar Salvador , Dave Hansen , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Catalin Marinas , Will Deacon , Mark Rutland , Kevin Brodsky , Alexander Gordeev , Alistair Popple , linux-mm@kvack.org, linux-riscv@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Muchun Song References: <20261010112457.49485-1-songmuchun@bytedance.com> <20261010112457.49485-3-songmuchun@bytedance.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/10/26 13:24, Muchun Song wrote: > RISC-V uses the same memory-hotplug teardown code for linear-map and > vmemmap page tables. Late linear-map allocations run page-table > constructors, while vmemmap and early allocations may not. > > free_pte_table() unconditionally calls pagetable_dtor(), corrupting > NR_PAGETABLE accounting for constructor-free tables. free_pmd_table() > avoids that for vmemmap using is_vmemmap, but mapping type is not a > reliable proxy for constructor state. In particular, it becomes invalid > once runtime vmemmap tables use the normal pgalloc helpers. > > Introduce free_pgtable_page() to select free_reserved_page() for reserved > pages and pagetable_free() otherwise. The latter runs the destructor only > when PageTable() is set, handling both constructor-backed and > constructor-free tables. > > Fixes: c75a74f4ba19 ("riscv: mm: Add memory hotplugging support") > Cc: stable@vger.kernel.org > Assisted-by: LLM > Signed-off-by: Muchun Song > --- Acked-by: David Hildenbrand (Arm) -- Cheers, David