From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from out1-smtp.messagingengine.com ([66.111.4.25]:39157 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726767AbfAGVFV (ORCPT ); Mon, 7 Jan 2019 16:05:21 -0500 From: Nikolaus Rath To: Miklos Szeredi Cc: fuse-devel , Miklos Szeredi , linux-fsdevel Subject: Re: [fuse-devel] fuse: trying to steal weird page References: <87o998m0a7.fsf@vostro.rath.org> Date: Mon, 07 Jan 2019 21:05:16 +0000 In-Reply-To: (Miklos Szeredi's message of "Mon, 7 Jan 2019 09:28:15 +0100") Message-ID: <87ef9omb5f.fsf@vostro.rath.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Jan 07 2019, Miklos Szeredi wrote: > On Wed, Dec 26, 2018 at 10:44 PM Nikolaus Rath wrote: >> >> Hi, >> >> I am seeing relatively regular occurences of >> >> $ sudo dmesg | tail >> [21929.138815] fuse: trying to steal weird page >> [21929.138821] page=3D00000000a7dd2617 index=3D64 flags=3D17fffc0000000a= d, >> count=3D1, mapcount=3D0, mapping=3D (null) >> [21930.647338] fuse: trying to steal weird page >> [21930.647345] page=3D00000000a07f32af index=3D2848 >> flags=3D17fffc0000000ad, count=3D1, mapcount=3D0, mapping=3D (null) >> [21932.338873] fuse: trying to steal weird page >> [21932.338879] page=3D0000000067e3a012 index=3D64 flags=3D17fffc0000000a= d, >> count=3D1, mapcount=3D0, mapping=3D (null) >> [21933.930703] fuse: trying to steal weird page >> [21933.930710] page=3D00000000046feb25 index=3D845 >> flags=3D17fffc0000000ad, count=3D1, mapcount=3D0, mapping=3D (null) >> [21936.163174] fuse: trying to steal weird page >> [21936.163180] page=3D00000000fb80fe27 index=3D0 flags=3D17fffc0000000ad, >> count=3D1, mapcount=3D0, mapping=3D (null) > > The page has the PG_dity and PG_waiters flags set which are > incompatible with stealing. page_cache_pipe_buf_steal() does > apparently filter out dirty ones, so it's not a regular file that we > are trying to streal the page from. So the question is: what is the > source of the splice()? =20 Hmm. I think it has to be a regular file. But as I mentioned in my other email, I did have a race condition where fd's were closed incorrectly. Is it possible that this also triggered the above, i.e. that the fd was closed sometime during splice? Best, -Nikolaus --=20 GPG Fingerprint: ED31 791B 2C5C 1613 AF38 8B8A D113 FCAC 3C4E 599F =C2=BBTime flies like an arrow, fruit flies like a Banana.=C2= =AB