APPLIED: [PATCH 0/2][SRU][ARTFUL] Fix VFS warning and file system resize failure (LP: #1726818)

[Khaled Elmously]

On 2018-02-02 10:28:43 , Khaled Elmously wrote:
> On 2018-02-02 12:00:34 , Kleber Souza wrote:
> > Hi Khaled,
> > 
> > Commit for patch 1/2 is missing the fix for the original author. Commit
> > for patch 2/2 is missing the SOB from Colin and the upstream sha1 line.
> > Both commits are missing your ACK (the commit should contain all the
> > ACK's from the mailing-list plus the SOB from the person applying it,
> > even if the same person also ACK'ed or is the original author or
> > submitter).
> 
> "..even if the same person also ACK'ed" I think this is the part where I may have received conflicting information. I will try to lean more towards your method of doing things since it appears you feel more strongly about it than Kamal does :) (also more information is generally better)
> 
> 
> > The patches were applied in the wrong order
> 
> This is also something that I had discussed with Kamal. I had to go back in my git history and amend a few commits so the order of commits changed. I had asked if order is important and he stated it's not. However, now that I think about it, he may have been referring to orders of *patchsets*, not order of patches _within_ a patchset.
> 

I've fixed the order of these 2 patches (and Kamal pushed it to master-next-backlog), so at least the order should be good now.

Thanks
-Khaled

> I will be more mindful of that in the future, thanks.
> 
> 
> -Khaled
> 
> 
> > 
> > 
> > Thanks,
> > Kleber
> > 
> > On 02/01/18 21:26, Khaled Elmously wrote:
> > > Applied to artful
> > > 
> > > On 2017-11-21 17:05:26 , Colin King wrote:
> > >> From: Colin Ian King <colin.king at canonical.com>
> > >>
> > >> The following two patches fix a VFS warning and a file system resize failure
> > >> on Artful when booting a virtual image using a vagrant/VirtualBox combo.
> > >>
> > >> [SRU Justfication, Artful]
> > >>
> > >> [Impact]
> > >>
> > >> Booting the 4.13 Artful kernel with vagrant using VirtualBox trips the warning:
> > >>
> > >> [ 61.010337] VFS: brelse: Trying to free free buffer
> > >> [ 61.114875] ------------[ cut here ]------------
> > >> [ 61.114886] WARNING: CPU: 0 PID: 683 at /build/linux-XO_uEE/linux-4.13.0/fs/buffer.c:1205 __brelse+0x21/0x30
> > >>
> > >> and a failed resize of a partition. The root cause has been bisected down
> > >> to the following commmit:
> > >>
> > >> commit c20cfc27a47307e811346f85959cf3cc07ae42f9
> > >> Author: Christoph Hellwig <hch at lst.de>
> > >> Date: Wed Apr 5 19:21:07 2017 +0200
> > >>
> > >>     block: stop using blkdev_issue_write_same for zeroing
> > >>
> > >> [Fix]
> > >> The Upstream commit directly fixes this issue:
> > >>
> > >> commit d5ce4c31d6df518dd8f63bbae20d7423c5018a6c
> > >> Author: Ilya Dryomov <idryomov at gmail.com>
> > >> Date: Mon Oct 16 15:59:10 2017 +0200
> > >>
> > >>     block: cope with WRITE ZEROES failing in blkdev_issue_zeroout()
> > >>
> > >> ..however we also require a backport of the following upstream commit to apply
> > >> the above commit cleanly:
> > >>
> > >> commit 425a4dba7953e35ffd096771973add6d2f40d2ed
> > >> Author: Ilya Dryomov <idryomov at gmail.com>
> > >> Date: Mon Oct 16 15:59:09 2017 +0200
> > >>
> > >>     block: factor out __blkdev_issue_zero_pages()
> > >>
> > >> [Testscase]
> > >>
> > >> On Ubuntu Xenial:
> > >>
> > >> 1. sudo apt-get install virtualbox vagrant
> > >> 2. edit /etc/group and add one's user name to the vboxusers group
> > >> 3. log out log back
> > >> 4. vagrant init ubuntu/artful64
> > >> 5. vagrant up
> > >> 6. vagrant ssh
> > >> 7. dmesg | grep "VFS: brelse"
> > >>
> > >> without the fix one will see the VFS brelse warning message and the /
> > >> partition will not have been resized.
> > >>
> > >> with a fixed system there is is no VFS vbrelse warning and / as been
> > >> resized as expected.
> > >>
> > >> [Regresion potential]
> > >> These patches touch the blk library so potentially it could break the block
> > >> layer and corrupt data on disk. However these are upstream fixes that address
> > >> the buggy commit c20cfc27a47307e811346f85959cf3cc07ae42f9 and are known to
> > >> address the bug.
> > >>
> > >> Colin Ian King (1):
> > >>   block: factor out __blkdev_issue_zero_pages()
> > >>
> > >> Ilya Dryomov (1):
> > >>   block: cope with WRITE ZEROES failing in blkdev_issue_zeroout()
> > >>
> > >>  block/blk-lib.c | 108 +++++++++++++++++++++++++++++++++++++-------------------
> > >>  1 file changed, 72 insertions(+), 36 deletions(-)
> > >>
> > >> -- 
> > >> 2.7.4
> > >>
> > >>
> > >> -- 
> > >> kernel-team mailing list
> > >> kernel-team at lists.ubuntu.com
> > >> https://lists.ubuntu.com/mailman/listinfo/kernel-team
> > >