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 E95BE38F259 for ; Wed, 1 Jul 2026 04:53:59 +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=1782881640; cv=none; b=CN3S18r/6q69TVToaFE34ZqjfTWcSMickGnCuhsajpsoZUBMF7mMMDsdCHKIZLmDp2kP2b/Uwyecs/9DsRWT7c+WmHTKuEnyP06H7/kNNrDSSzd0BXNmhussqtBNcmFxarxTbYNvNpV66BmAypM5PcP0k+BzTdVScpRS5hfX4QU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782881640; c=relaxed/simple; bh=EIgMAzLbEX9gioU8NIlY9g3LjhDlGcllIiaJLhPiWDM=; h=Message-ID:Date:MIME-Version:Subject:From:To:Cc:References: In-Reply-To:Content-Type; b=hovJNbqIcJSDWkjml+B3pq/c0ieDE+yeG+jPUqwzB1FD5M0YQ0W/fhg16KkDLdGLDZ9eEor7fYptvuuMeVI9Gi0bN4AFeQoEhSmCzuxX/vun00tu7FD3NmssYnEu928NcQGMGrJrg4P0f4KGlEF+KhbpuDOLqXvpjr081JScotE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CWZ/iO/x; 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="CWZ/iO/x" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BCD731F000E9; Wed, 1 Jul 2026 04:53:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782881639; bh=PPObPGqbn58a+BSBCY9J0jUKRs+BuD8Ze2qKuyhsnqY=; h=Date:Subject:From:To:Cc:References:In-Reply-To; b=CWZ/iO/xxxWxdnqhN1v0bjq/8gJTOrd/6LXlYt/FvCEyNWN6jQwKl6fhJqtNwI+Ka tlF5twq8OQwsrJrd+EPQwH3RRenp8REV6ePIBewX4A6meMloXxnSsoBS1rdXSzSJzG zneKOMqWJkwmlChWIJvRm8h3keUFy64nUf6bvMubuvxxnRNYmI0wle4dwU0Hsx9Bg7 7w5ToxoYVIqNRI3zGgJKimOl/4foFGHdm2d8gcxSzgNRcx6X6IEXaealLHwVdBeIvU a0K2bOYSIwsqsSSDj2xia9txJ6og2vlgGFvioNgvaJ65QLztfbr6SGiRZSrwSYBHov wOG1PBdcHT1ag== Message-ID: <92bf5e21-690e-4a77-929e-5217e0d7cb0c@kernel.org> Date: Wed, 1 Jul 2026 13:53:50 +0900 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] mm/slub: serve slabobj_ext array from a strictly larger kmalloc cache From: Harry Yoo To: Suren Baghdasaryan Cc: Shakeel Butt , "Vlastimil Babka (SUSE)" , Andrew Morton , Roman Gushchin , Hao Li , Christoph Lameter , David Rientjes , Usama Arif , Meta kernel team , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Danielle Costantino , Kees Cook References: <62969830-4b1f-483d-8fa9-9ce487568570@kernel.org> <39a79576-dcae-4b66-9478-c81dfe676699@kernel.org> <5ebd3c4a-5c06-43b4-ab0a-7a8f0396c84c@kernel.org> <9a139365-28e6-4f1e-b35b-7f6091e9aa14@kernel.org> Content-Language: en-US In-Reply-To: <9a139365-28e6-4f1e-b35b-7f6091e9aa14@kernel.org> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------Kwww120eW5YN9o9Iu8Wli0oM" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --------------Kwww120eW5YN9o9Iu8Wli0oM Content-Type: multipart/mixed; boundary="------------gIXJXbeJJd2qmAqBY9E95a70"; protected-headers="v1" From: Harry Yoo To: Suren Baghdasaryan Cc: Shakeel Butt , "Vlastimil Babka (SUSE)" , Andrew Morton , Roman Gushchin , Hao Li , Christoph Lameter , David Rientjes , Usama Arif , Meta kernel team , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Danielle Costantino , Kees Cook Message-ID: <92bf5e21-690e-4a77-929e-5217e0d7cb0c@kernel.org> Subject: Re: [PATCH] mm/slub: serve slabobj_ext array from a strictly larger kmalloc cache References: <62969830-4b1f-483d-8fa9-9ce487568570@kernel.org> <39a79576-dcae-4b66-9478-c81dfe676699@kernel.org> <5ebd3c4a-5c06-43b4-ab0a-7a8f0396c84c@kernel.org> <9a139365-28e6-4f1e-b35b-7f6091e9aa14@kernel.org> In-Reply-To: <9a139365-28e6-4f1e-b35b-7f6091e9aa14@kernel.org> --------------gIXJXbeJJd2qmAqBY9E95a70 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 7/1/26 1:30 PM, Harry Yoo wrote: > We can do that in pre-7.2 kernels, by teaching kmalloc_type() and > kmalloc_slab() select the new KMALLOC_TYPE based on __GFP_NO_OBJ_EXT? >=20 > e.g.) Select the new KMALLOC_TYPE when KMALLOC_NOT_NORMAL_BITS is not > set AND __GFP_NO_OBJ_EXT is set. Uh, this is bit subtle though. In some cases KMALLOC_DMA =3D=3D KMALLOC_NORMAL, KMALLOC_CGROUP =3D=3D KMALLOC_NORMAL, or KMALLOC_RECLAIM =3D=3D KMALLOC_NORMAL. Just checking KMALLOC_NOT_NORMAL_BITS is misleading. > This doesn't require kmem_buckets and should be much simpler. --=20 Cheers, Harry / Hyeonggon --------------gIXJXbeJJd2qmAqBY9E95a70-- --------------Kwww120eW5YN9o9Iu8Wli0oM Content-Type: application/pgp-signature; name="OpenPGP_signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="OpenPGP_signature.asc" -----BEGIN PGP SIGNATURE----- iHUEARYKAB0WIQQQ1ub6gR5ogjaKRmOGXBN6rc5S1gUCakSdXgAKCRCGXBN6rc5S 1mR+AP9Xlm5j7mV0bXzXndD3BUVjxM5Q2kRZbrCfD/VvS8Ld4AEAxRCvXIFVvGM3 leoCa/1kGSjB2HI29YUbII181TMFBw8= =xFlG -----END PGP SIGNATURE----- --------------Kwww120eW5YN9o9Iu8Wli0oM--