From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-246.mta1.migadu.com [95.215.58.246]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 274273EC82B for ; Tue, 22 Sep 2026 08:06:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.246 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790064417; cv=none; b=bLb44aI1H+eh0qvPd6/vqrie+JJS5PkDvHWtVoNWjaqtuVX5dkUPulWQcBY7AbPLtnw8CqxwBQb1YXDNaIuxuknFw5LltNXMd+uQP3vlw8WG1RjxWVuWfmZ7Mj8xaPHMCt+vu+t+4HLuKgKgyPoYSMG5ZiEOKOmELm1/mSkU4SE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790064417; c=relaxed/simple; bh=L3E1ABTsvQD+v6c+2rBUEff5SSrYDo8CA8Cr1zQwot4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=fdmpuBql9qGcsmmk13At0+ANfFt3+CMLuy5cKxu6eBQuhVGAa3582V+wHU2ZustuN54Jm44VsbZ+z9VA2g4gi32FbNRDZNWcuY/zohXvvfCwzHEjxNFRaKOHE6QVf+y1fszQvsz1gYf0SMH2xmipXOMqus5Eus8tUnlSTWKild4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=pZWTZU4L; arc=none smtp.client-ip=95.215.58.246 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="pZWTZU4L" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=L3E1ABTsvQD+v6c+2rBUEff5SSrYDo8CA8Cr1zQwot4=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1790064404; v=1; x=1790669204; b=pZWTZU4LUhgakPVLGPX5D3FFmTpz3l4NLv1Dxd8Hh3GY6WQ89/zEBlXWSy5IxOqeZKiwBf+I szl3QUQlqfANKxTdOHbhlH8HoCr7f/+XDZoOK/y8NyoC+YxoDfPuHfOsRIX8BFlcR76U/bkOlLw w+UG/W3InrzU8AMWSb8ChDwA= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 69a7d16cab5036eb; Tue, 22 Sep 2026 08:06:44 +0000 X-Mizu-Trace-ID: 69a7d16cab5036eb X-Migadu-Flow: FLOW_OUT Message-ID: <8a135fee-1f75-4260-afa0-10f8b522809f@linux.dev> Date: Tue, 22 Sep 2026 16:06:38 +0800 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 3/6] mm/sparse-vmemmap: drop Device DAX-specific population path To: Muchun Song , Madhavan Srinivasan , Mike Rapoport , Andrew Morton , David Hildenbrand Cc: Michael Ellerman , Nicholas Piggin , Christophe Leroy , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, muchun.song@linux.dev References: <20260913083734.86802-1-songmuchun@bytedance.com> <20260913083734.86802-4-songmuchun@bytedance.com> From: Qi Zheng In-Reply-To: <20260913083734.86802-4-songmuchun@bytedance.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 9/13/26 4:37 PM, Muchun Song wrote: > The common vmemmap path selects the shared page for optimized mappings > itself, so Device DAX no longer needs vmemmap_populate_compound_pages() > to find a shared tail page and pass its backing PFN through the generic > population helpers. > > Remove the Device DAX-specific population path and let section memmap > population always use vmemmap_populate(). The powerpc retains an > architecture-specific compound-page implementation, so select it directly > from radix__vmemmap_populate() for optimizable sections. > > Signed-off-by: Muchun Song > --- > arch/powerpc/mm/book3s64/radix_pgtable.c | 3 + > mm/mm_init.c | 2 +- > mm/sparse-vmemmap.c | 71 +----------------------- > 3 files changed, 5 insertions(+), 71 deletions(-) Acked-by: Qi Zheng Thanks, Qi