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 DA562478E45 for ; Thu, 27 Aug 2026 15:25:27 +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=1787844330; cv=none; b=G6LoT1aBDx065K4RqDtqzcs8DF6/nmXPWCnaPXoHZR8pXi93v09SbFsHG1RPHzZhYfkNbZ2M1eVogZ9gETebc8/XXE5nN4y56xP5ywZ0rUD3XkJyVwjYk4mLRjUCHfnWPFMJhYdTy2ge0Y3XJ7/GcYiqyqKDj6oloNaRMbfCpUI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787844330; c=relaxed/simple; bh=r5m2ovA5CfuVVotpjBek4NDN2rGJF6IkFI+xbMkLbBg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=oPVGLIbmZGNMTFBFXIEIFeIObLKqqYnXruQXhnuaKf5hohupGa3A8t+q9uGPznTcn7f/n5hnhIPMa2Wy87mPxTh/OhVX4gRdayMTJKKIawPQXYoi6MabHja4PTTYC4rhFaMorhK0abglDDc+4Mf+xcpH4jbrahWSJMCoGHi7i/Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=n7/r67hd; 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="n7/r67hd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7F5131F000E9; Thu, 27 Aug 2026 15:25:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787844326; bh=GIsr8YGMo1u0diDgy7h2P49ddYFTWI12rSRTVLjwN7Q=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=n7/r67hdM7EezCfE26KRK2p12eJIjZ/zBDqUya+yxx8kActvRK0dT6D7YnTi8zp3D 4d41BK6Qpq5Gyo33Nn/djyf1JLp+a4OUfKCnwamvZClFSEfqe1xw8KMKtrRMx++6ft Ow8m1WQnc+JA/ePg6/Nm1V4PxbQBpYvMangBE/7J9Hnb6c/agMyESFVPsK8T12pg1g TZlP00Ox1zyDN6UaJ3gJqRVw8PmIs0bP5cMSVTIDqUa0I0rui9YuhokAOUrA33H+6e JLZaOPwp/rabQ0jLFDyNc3W18u0ttP62T2oxjTaGDzxy4RngOy71oJMnLZVDR/DRsh znLuRviPpcegg== Message-ID: Date: Thu, 27 Aug 2026 17:25:20 +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 2/5] mm/huge_memory: dequeue the deferred split after the split freeze To: Kiryl Shutsemau , akpm@linux-foundation.org, ljs@kernel.org, hannes@cmpxchg.org, usama.arif@linux.dev Cc: lance.yang@linux.dev, ziy@nvidia.com, hughd@google.com, baolin.wang@linux.alibaba.com, baohua@kernel.org, liam@infradead.org, nico.pache@linux.dev, dev.jain@arm.com, ryan.roberts@arm.com, balbirs@nvidia.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kiryl Shutsemau (Meta)" References: <20260826162101.1314941-1-kirill@shutemov.name> <20260826162101.1314941-3-kirill@shutemov.name> 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 8/26/26 18:20, Kiryl Shutsemau wrote: > From: "Kiryl Shutsemau (Meta)" > > __folio_freeze_and_split_unmapped() takes the deferred split list_lru lock > across the freeze. It is only there to stop deferred_split_scan() from > touching the folio under split. > > With deferred_split_isolate() fixed, the workaround can be dropped. > > Unqueue the folio after folio_ref_freeze(), the way > __folio_migrate_mapping() does: folio_unqueue_deferred_split() needs a > zero refcount and a memcg still set, and both hold there. > > If the split is called from deferred_split_scan(), the unqueue is a > no-op -- the folio is already removed from the list. But > PG_partially_mapped is still set, so it has to be cleared here or > MTHP_STAT_NR_ANON_PARTIALLY_MAPPED never comes back down. > > Assisted-by: Claude-Code:claude-opus-5 > Signed-off-by: Kiryl Shutsemau (Meta) > --- LGTM! Acked-by: David Hildenbrand (Arm) -- Cheers, David