From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from manchmal.in-ulm.de (manchmal.in-ulm.de [217.10.9.201]) (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 A1EE01EEE6; Sun, 14 Sep 2025 17:15:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.10.9.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757870136; cv=none; b=CJayQrfaaL4hQvAGytbrEdEZ2SmPxmZ/Ki+Ux30K88Yx+QNCNdcWK/Z3V77ZzFfTqWeiUI2ktk6GDo7E/h2HrCtY0jINGtQ5C3M6cBVNWLeipL/73GqSaG2Ig/wZ3wYEpb545wxd698kcF67+dOR/uuLa3W7QKuRGFZtLuZInDY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757870136; c=relaxed/simple; bh=mCY7CFjzHorofJ89F2uXcM9RFrcQISKb9+9Ln9zOgO8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Q8bs8fJyQtAXBLUAsy5uH6KoZYSq0VSLlSUno1oYYt5/b0YdkThP+mRV8EYZVa558uBGaJmUpk2wfJwJclZBnacp6Rr+YoTo9hGF50DCKu65ulEqmmk9izG+qtkbJQgyP6VCKvxHa9/D99DQhN9efdd/H5DlAEunz+4/9H64yaQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=manchmal.in-ulm.de; spf=pass smtp.mailfrom=manchmal.in-ulm.de; arc=none smtp.client-ip=217.10.9.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=manchmal.in-ulm.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=manchmal.in-ulm.de Date: Sun, 14 Sep 2025 19:06:12 +0200 From: Christoph Biedl To: Helge Deller Cc: David Hildenbrand , Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= , Jesper Dangaard Brouer , Ilias Apalodimas , "David S. Miller" , Linux Memory Management List , netdev@vger.kernel.org, Linux parisc List , Andrew Morton Subject: Re: [PATCH][RESEND][RFC] Fix 32-bit boot failure due inaccurate page_pool_page_is_pp() Message-ID: <1757869448@msgid.manchmal.in-ulm.de> References: Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="yGQQKzeyEZMtAyaE" Content-Disposition: inline In-Reply-To: --yGQQKzeyEZMtAyaE Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Helge Deller wrote... > Commit ee62ce7a1d90 ("page_pool: Track DMA-mapped pages and unmap them wh= en > destroying the pool") changed PP_MAGIC_MASK from 0xFFFFFFFC to 0xc000007c= on > 32-bit platforms. >=20 > The function page_pool_page_is_pp() uses PP_MAGIC_MASK to identify page p= ool > pages, but the remaining bits are not sufficient to unambiguously identify > such pages any longer. >=20 > So page_pool_page_is_pp() now sometimes wrongly reports pages as page pool > pages and as such triggers a kernel BUG as it believes it found a page po= ol > leak. >=20 > There are patches upcoming where page_pool_page_is_pp() will not depend on > PP_MAGIC_MASK and instead use page flags to identify page pool pages. Unt= il > those patches are merged, the easiest temporary fix is to disable the che= ck > on 32-bit platforms. >=20 > Cc: Jesper Dangaard Brouer > Cc: Ilias Apalodimas > Cc: David Hildenbrand > Acked-by: David Hildenbrand > Cc: Toke H=C3=B8iland-J=C3=B8rgensen > Cc: Linux Memory Management List > Cc: netdev@vger.kernel.org > Cc: Linux parisc List > Cc: # v6.15+ > Signed-off-by: Helge Deller > Link: https://www.spinics.net/lists/kernel/msg5849623.html > Fixes: ee62ce7a1d90 ("page_pool: Track DMA-mapped pages and unmap them wh= en destroying the pool") Tested-by: Christoph Biedl --yGQQKzeyEZMtAyaE Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEWXMI+726A12MfJXdxCxY61kUkv0FAmjG9gAACgkQxCxY61kU kv2OKg/+I5r7SmuFKfUeJR8lmfesg5+t/EObRKadkYWCImIHaUX2omjB2mblcKP8 3HrhbTGSJvEaqud7y12GGP62Q0elxTUxBQmjedaIibtL0oknVyPwiFrVGrKQ5nPR Q9DQNFh6GEIiiME2uWh+gmc2lVz8mLnrxtZj/eTlNXYCRwKz9GgEgOVEeJDSrHNE wcFJQH5Yvteb8n3C1opZNO2+uokGahlH0OCfEFZsGvaFdvusRgTAlyNyV9PXzAlM okIqWJv8EABX3Zfl8+GA82FSTGT8Bn4sQRu5IrXarzM2POw/nlYnQP36RJrFe6M0 9tFkaLTcKaYWhWSZ8YxtfWjbGufGYNhikqgL5w9MSAeH3twAGGFbx03Q0dzUT8XC xwq0gfQqGagnADmtvHXF40PTSjeb98El2QQ/Vz/fV/dfJcn6EbNjzYraKtMuMZuX BlI6wxJEaj/PaGjpPeQ1FcMmuJYSbW/6TKEB8gD5Hgmh0ngbZQ5zJuM1AR0Oe/JZ mhsio08zmXM8A0wIvWXFsrXsXzSV3hXn9I+sn4DAMz9gx3+O/Ek9/wbww9rcA4lH DU/zroDnn050JvMJZr00pCFmYeBuvy8cWE3sh6tgN0kdSRUPb222KGLD4dZxfPag 3LuZXw/cgYGtMgw6RxtuiY6nfrouzsYLrQJBNoseZTYCn3VCxNE= =Qki2 -----END PGP SIGNATURE----- --yGQQKzeyEZMtAyaE--