From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mandeep Singh Baines Subject: Re: [dm-crypt] Kernel BUG (fs/bio.c:1499) when copying more files to an encrypted device Date: Wed, 25 Jan 2012 15:46:12 -0800 Message-ID: <20120125234612.GM4656@google.com> References: <20120125021413.GI4656@google.com> <1327478794.47118.YahooMailClassic@web24104.mail.ird.yahoo.com> <20120125182027.GJ4656@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20120125182027.GJ4656@google.com> Content-Disposition: inline Sender: linux-raid-owner@vger.kernel.org To: Mandeep Singh Baines Cc: Luzipher McLeod , dm-crypt@saout.de, linux-raid@vger.kernel.org List-Id: linux-raid.ids +cc linux-raid Mandeep Singh Baines (msb@chromium.org) wrote: > Luzipher McLeod (luziphermcleod@yahoo.ie) wrote: > > Hi Mandeep, > >=20 > > Thanks fpr your quick answer. So, what can be done about this ? Sho= uld I try to apply that patch you linked to ? (but I guess a patch from= 2007 won't apply cleanly ...) > >=20 >=20 > Hi Luzipher, >=20 > I wouldn't apply the patch directly. Just copy bio_multi_split (might > need to do some forward porting) and then modify linear_make_request = to > use bio_multi_split instead of bio_split. >=20 > But I'm not really an expert on this particular code. I'm hoping some= one > else will confirm that this is in fact the bug and not a side effect = of > something else. Its seem reasonble that you could get a bio that is > multi-page and falls on a boundary (spans two or more devices). So I > suspect this is the bug. >=20 > Regards, > Mandeep >=20 > > Regards, > > Luzipher > >=20 > >=20 > >=20 > > --- On Wed, 25/1/12, Mandeep Singh Baines wrote: > >=20 > > > From: Mandeep Singh Baines > > > Subject: Re: [dm-crypt] Kernel BUG (fs/bio.c:1499) when copying m= ore files to an encrypted device > > > To: "Luzipher McLeod" > > > Cc: dm-crypt@saout.de, "NeilBrown" > > > Date: Wednesday, 25 January, 2012, 2:14 > > > Luzipher McLeod (luziphermcleod@yahoo.ie) > > > wrote: > > > > Hi :-) > > > >=20 > > > > A few days ago I encountered a kernel bug while copying > > > files to an encrypted filesystem. The specific stack for the > > > filesystem is: btrfs-on-crypt-on-mdraid. Vasts amounts of > > > data copied without problems (about 6.3TB with 1.1 TB > > > remaining), but when copying a certain directory, the kernel > > > bug surfaces. I repeatedly deleted the affected directory > > > and tried to re-copy it, but it always fails at the same > > > point (or close to that). More recent test showed that I > > > could copy a few more files to the filesystem to a different > > > directory, but it very quickly failed there as well (a few > > > megabytes later). > > > > After talking to the btrfs devs on freenode (as btrfs > > > is the most experimental thing in the stack, they came to > > > the conclusion that it's most probably the crypto layer. > > > >=20 > > > > Some details: > > > > gentoo kernel 3.2.1 (custom config and ubuntu config) > > > > mdraid: linear, 4 disks, each 2TB (total 8TB) > > > > crypt: setup via cryptsetup -c aes-xts-plain64 -h plain > > > -s 512 -d - create tempraid /dev/md/tempraid_lin > > > >=20 > > > > I'd appreciate any help with this and would be happy to > > > test patches or provide more debug info. > > > >=20 > > > > Thanks and Regards, > > > > Luzipher > > > >=20 > > > >=20 > > > >=20 > > > >=20 > > > > The kernel bug output retrieved by netconsole (also at > > > http://pastebin.com/sjJy7QE4 ): > > > >=A0 =A0=A0=A0[=A0 294.538422] netconsole: > > > local port 6666 > > > >=A0 =A0=A0=A0[=A0 333.423583] SysRq : > > > Changing Loglevel > > > >=A0 =A0=A0=A0[=A0 333.423609] Loglevel > > > set to 9 > > > >=A0 =A0=A0=A0[=A0 424.248405] > > > ------------[ cut here ]------------ > > > >=A0 =A0=A0=A0[=A0 424.248447] kernel BUG > > > at fs/bio.c:1499! > > >=20 > > > Hi Luzipher, > > >=20 > > > Looks like the BUG is because bio_split only works on > > > single-page iovecs. > > >=20 > > > I see a relevant (old) patch from Neil Brown here: > > >=20 > > > https://lkml.org/lkml/2007/7/30/496 > > >=20 > > > Regards, > > > Mandeep > > >=20 > >=20 -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html