FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

[gregkh]

The patch below does not apply to the 4.17-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From db6516a5e7ddb6dc72d167b920f2f272596ea22d Mon Sep 17 00:00:00 2001
From: Amir Goldstein <amir73il@gmail.com>
Date: Sun, 13 May 2018 22:54:44 -0400
Subject: [PATCH] ext4: do not update s_last_mounted of a frozen fs

If fs is frozen after mount and before the first file open, the
update of s_last_mounted bypasses freeze protection and prints out
a WARNING splat:

$ mount /vdf
$ fsfreeze -f /vdf
$ cat /vdf/foo

[   31.578555] WARNING: CPU: 1 PID: 1415 at
fs/ext4/ext4_jbd2.c:53 ext4_journal_check_start+0x48/0x82

[   31.614016] Call Trace:
[   31.614997]  __ext4_journal_start_sb+0xe4/0x1a4
[   31.616771]  ? ext4_file_open+0xb6/0x189
[   31.618094]  ext4_file_open+0xb6/0x189

If fs is frozen, skip s_last_mounted update.

[backport hint: to apply to stable tree, need to apply also patches
 vfs: add the sb_start_intwrite_trylock() helper
 ext4: factor out helper ext4_sample_last_mounted()]

Cc: stable@vger.kernel.org
Fixes: bc0b0d6d69ee ("ext4: update the s_last_mounted field in the superblock")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index c48ea76b63e4..7f8023340eb8 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -393,7 +393,7 @@ static int ext4_sample_last_mounted(struct super_block *sb,
 	if (likely(sbi->s_mount_flags & EXT4_MF_MNTDIR_SAMPLED))
 		return 0;
 
-	if (sb_rdonly(sb))
+	if (sb_rdonly(sb) || !sb_start_intwrite_trylock(sb))
 		return 0;
 
 	sbi->s_mount_flags |= EXT4_MF_MNTDIR_SAMPLED;
@@ -407,21 +407,25 @@ static int ext4_sample_last_mounted(struct super_block *sb,
 	path.mnt = mnt;
 	path.dentry = mnt->mnt_root;
 	cp = d_path(&path, buf, sizeof(buf));
+	err = 0;
 	if (IS_ERR(cp))
-		return 0;
+		goto out;
 
 	handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
+	err = PTR_ERR(handle);
 	if (IS_ERR(handle))
-		return PTR_ERR(handle);
+		goto out;
 	BUFFER_TRACE(sbi->s_sbh, "get_write_access");
 	err = ext4_journal_get_write_access(handle, sbi->s_sbh);
 	if (err)
-		goto out;
+		goto out_journal;
 	strlcpy(sbi->s_es->s_last_mounted, cp,
 		sizeof(sbi->s_es->s_last_mounted));
 	ext4_handle_dirty_super(handle, sb);
-out:
+out_journal:
 	ext4_journal_stop(handle);
+out:
+	sb_end_intwrite(sb);
 	return err;
 }
 

Re: FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

[Amir Goldstein]

On Fri, Jun 22, 2018 at 12:15 AM,  <gregkh@linuxfoundation.org> wrote:
>
> The patch below does not apply to the 4.17-stable tree.

There is a [backport hint] at the end of the commit message.
Need to take the 2 prep commits.
Same for all stable branches.

Cheers,
Amir.

> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@vger.kernel.org>.
>
> thanks,
>
> greg k-h
>
> ------------------ original commit in Linus's tree ------------------
>
> From db6516a5e7ddb6dc72d167b920f2f272596ea22d Mon Sep 17 00:00:00 2001
> From: Amir Goldstein <amir73il@gmail.com>
> Date: Sun, 13 May 2018 22:54:44 -0400
> Subject: [PATCH] ext4: do not update s_last_mounted of a frozen fs
>
> If fs is frozen after mount and before the first file open, the
> update of s_last_mounted bypasses freeze protection and prints out
> a WARNING splat:
>
> $ mount /vdf
> $ fsfreeze -f /vdf
> $ cat /vdf/foo
>
> [   31.578555] WARNING: CPU: 1 PID: 1415 at
> fs/ext4/ext4_jbd2.c:53 ext4_journal_check_start+0x48/0x82
>
> [   31.614016] Call Trace:
> [   31.614997]  __ext4_journal_start_sb+0xe4/0x1a4
> [   31.616771]  ? ext4_file_open+0xb6/0x189
> [   31.618094]  ext4_file_open+0xb6/0x189
>
> If fs is frozen, skip s_last_mounted update.
>
> [backport hint: to apply to stable tree, need to apply also patches
>  vfs: add the sb_start_intwrite_trylock() helper
>  ext4: factor out helper ext4_sample_last_mounted()]
>
> Cc: stable@vger.kernel.org
> Fixes: bc0b0d6d69ee ("ext4: update the s_last_mounted field in the superblock")
> Signed-off-by: Amir Goldstein <amir73il@gmail.com>
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> Reviewed-by: Jan Kara <jack@suse.cz>
>
> diff --git a/fs/ext4/file.c b/fs/ext4/file.c
> index c48ea76b63e4..7f8023340eb8 100644
> --- a/fs/ext4/file.c
> +++ b/fs/ext4/file.c
> @@ -393,7 +393,7 @@ static int ext4_sample_last_mounted(struct super_block *sb,
>         if (likely(sbi->s_mount_flags & EXT4_MF_MNTDIR_SAMPLED))
>                 return 0;
>
> -       if (sb_rdonly(sb))
> +       if (sb_rdonly(sb) || !sb_start_intwrite_trylock(sb))
>                 return 0;
>
>         sbi->s_mount_flags |= EXT4_MF_MNTDIR_SAMPLED;
> @@ -407,21 +407,25 @@ static int ext4_sample_last_mounted(struct super_block *sb,
>         path.mnt = mnt;
>         path.dentry = mnt->mnt_root;
>         cp = d_path(&path, buf, sizeof(buf));
> +       err = 0;
>         if (IS_ERR(cp))
> -               return 0;
> +               goto out;
>
>         handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
> +       err = PTR_ERR(handle);
>         if (IS_ERR(handle))
> -               return PTR_ERR(handle);
> +               goto out;
>         BUFFER_TRACE(sbi->s_sbh, "get_write_access");
>         err = ext4_journal_get_write_access(handle, sbi->s_sbh);
>         if (err)
> -               goto out;
> +               goto out_journal;
>         strlcpy(sbi->s_es->s_last_mounted, cp,
>                 sizeof(sbi->s_es->s_last_mounted));
>         ext4_handle_dirty_super(handle, sb);
> -out:
> +out_journal:
>         ext4_journal_stop(handle);
> +out:
> +       sb_end_intwrite(sb);
>         return err;
>  }
>
>

Re: FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

[Greg KH]

On Fri, Jun 22, 2018 at 12:25:43AM +0300, Amir Goldstein wrote:
> On Fri, Jun 22, 2018 at 12:15 AM,  <gregkh@linuxfoundation.org> wrote:
> >
> > The patch below does not apply to the 4.17-stable tree.
> 
> There is a [backport hint] at the end of the commit message.
> Need to take the 2 prep commits.
> Same for all stable branches.

Doh!   Sorry about that, I'll go pay attention more and fix this up
myself.

greg k-h

Re: FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

[Greg KH]

On Fri, Jun 22, 2018 at 12:25:43AM +0300, Amir Goldstein wrote:
> On Fri, Jun 22, 2018 at 12:15 AM,  <gregkh@linuxfoundation.org> wrote:
> >
> > The patch below does not apply to the 4.17-stable tree.
> 
> There is a [backport hint] at the end of the commit message.
> Need to take the 2 prep commits.
> Same for all stable branches.
> 
> Cheers,
> Amir.
> 
> > If someone wants it applied there, or to any other stable or longterm
> > tree, then please email the backport, including the original git commit
> > id to <stable@vger.kernel.org>.
> >
> > thanks,
> >
> > greg k-h
> >
> > ------------------ original commit in Linus's tree ------------------
> >
> > From db6516a5e7ddb6dc72d167b920f2f272596ea22d Mon Sep 17 00:00:00 2001
> > From: Amir Goldstein <amir73il@gmail.com>
> > Date: Sun, 13 May 2018 22:54:44 -0400
> > Subject: [PATCH] ext4: do not update s_last_mounted of a frozen fs
> >
> > If fs is frozen after mount and before the first file open, the
> > update of s_last_mounted bypasses freeze protection and prints out
> > a WARNING splat:
> >
> > $ mount /vdf
> > $ fsfreeze -f /vdf
> > $ cat /vdf/foo
> >
> > [   31.578555] WARNING: CPU: 1 PID: 1415 at
> > fs/ext4/ext4_jbd2.c:53 ext4_journal_check_start+0x48/0x82
> >
> > [   31.614016] Call Trace:
> > [   31.614997]  __ext4_journal_start_sb+0xe4/0x1a4
> > [   31.616771]  ? ext4_file_open+0xb6/0x189
> > [   31.618094]  ext4_file_open+0xb6/0x189
> >
> > If fs is frozen, skip s_last_mounted update.
> >
> > [backport hint: to apply to stable tree, need to apply also patches
> >  vfs: add the sb_start_intwrite_trylock() helper
> >  ext4: factor out helper ext4_sample_last_mounted()]

For "hints", can you provide the git commit id in the future so I don't
have to dig them out myself?

thanks,

greg k-h

Re: FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

[Greg KH]

On Thu, Jul 05, 2018 at 06:27:01PM +0200, Greg KH wrote:
> On Fri, Jun 22, 2018 at 12:25:43AM +0300, Amir Goldstein wrote:
> > On Fri, Jun 22, 2018 at 12:15 AM,  <gregkh@linuxfoundation.org> wrote:
> > >
> > > The patch below does not apply to the 4.17-stable tree.
> > 
> > There is a [backport hint] at the end of the commit message.
> > Need to take the 2 prep commits.
> > Same for all stable branches.
> > 
> > Cheers,
> > Amir.
> > 
> > > If someone wants it applied there, or to any other stable or longterm
> > > tree, then please email the backport, including the original git commit
> > > id to <stable@vger.kernel.org>.
> > >
> > > thanks,
> > >
> > > greg k-h
> > >
> > > ------------------ original commit in Linus's tree ------------------
> > >
> > > From db6516a5e7ddb6dc72d167b920f2f272596ea22d Mon Sep 17 00:00:00 2001
> > > From: Amir Goldstein <amir73il@gmail.com>
> > > Date: Sun, 13 May 2018 22:54:44 -0400
> > > Subject: [PATCH] ext4: do not update s_last_mounted of a frozen fs
> > >
> > > If fs is frozen after mount and before the first file open, the
> > > update of s_last_mounted bypasses freeze protection and prints out
> > > a WARNING splat:
> > >
> > > $ mount /vdf
> > > $ fsfreeze -f /vdf
> > > $ cat /vdf/foo
> > >
> > > [   31.578555] WARNING: CPU: 1 PID: 1415 at
> > > fs/ext4/ext4_jbd2.c:53 ext4_journal_check_start+0x48/0x82
> > >
> > > [   31.614016] Call Trace:
> > > [   31.614997]  __ext4_journal_start_sb+0xe4/0x1a4
> > > [   31.616771]  ? ext4_file_open+0xb6/0x189
> > > [   31.618094]  ext4_file_open+0xb6/0x189
> > >
> > > If fs is frozen, skip s_last_mounted update.
> > >
> > > [backport hint: to apply to stable tree, need to apply also patches
> > >  vfs: add the sb_start_intwrite_trylock() helper
> > >  ext4: factor out helper ext4_sample_last_mounted()]
> 
> For "hints", can you provide the git commit id in the future so I don't
> have to dig them out myself?

And those backports don't apply properly :(

Can you please provide a series of patches backported to the stable
trees you feel these should go to, so I can apply them?

thanks,

greg k-h

Re: FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

[Amir Goldstein]

On Thu, Jul 5, 2018 at 7:29 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Thu, Jul 05, 2018 at 06:27:01PM +0200, Greg KH wrote:
>> On Fri, Jun 22, 2018 at 12:25:43AM +0300, Amir Goldstein wrote:
>> > On Fri, Jun 22, 2018 at 12:15 AM,  <gregkh@linuxfoundation.org> wrote:
>> > >
>> > > The patch below does not apply to the 4.17-stable tree.
>> >
>> > There is a [backport hint] at the end of the commit message.
>> > Need to take the 2 prep commits.
>> > Same for all stable branches.
>> >
>> > Cheers,
>> > Amir.
>> >
>> > > If someone wants it applied there, or to any other stable or longterm
>> > > tree, then please email the backport, including the original git commit
>> > > id to <stable@vger.kernel.org>.
>> > >
>> > > thanks,
>> > >
>> > > greg k-h
>> > >
>> > > ------------------ original commit in Linus's tree ------------------
>> > >
>> > > From db6516a5e7ddb6dc72d167b920f2f272596ea22d Mon Sep 17 00:00:00 2001
>> > > From: Amir Goldstein <amir73il@gmail.com>
>> > > Date: Sun, 13 May 2018 22:54:44 -0400
>> > > Subject: [PATCH] ext4: do not update s_last_mounted of a frozen fs
>> > >
>> > > If fs is frozen after mount and before the first file open, the
>> > > update of s_last_mounted bypasses freeze protection and prints out
>> > > a WARNING splat:
>> > >
>> > > $ mount /vdf
>> > > $ fsfreeze -f /vdf
>> > > $ cat /vdf/foo
>> > >
>> > > [   31.578555] WARNING: CPU: 1 PID: 1415 at
>> > > fs/ext4/ext4_jbd2.c:53 ext4_journal_check_start+0x48/0x82
>> > >
>> > > [   31.614016] Call Trace:
>> > > [   31.614997]  __ext4_journal_start_sb+0xe4/0x1a4
>> > > [   31.616771]  ? ext4_file_open+0xb6/0x189
>> > > [   31.618094]  ext4_file_open+0xb6/0x189
>> > >
>> > > If fs is frozen, skip s_last_mounted update.
>> > >
>> > > [backport hint: to apply to stable tree, need to apply also patches
>> > >  vfs: add the sb_start_intwrite_trylock() helper
>> > >  ext4: factor out helper ext4_sample_last_mounted()]
>>
>> For "hints", can you provide the git commit id in the future so I don't
>> have to dig them out myself?
>

That would be chicken and egg.
I wrote the hint when I posted the series so there was no upstream commit id
at the time. Maybe I should have written "need to apply the 2 previous patches"
as a hint... or could have tried to push back on review comments to split the
patches.

> And those backports don't apply properly :(
>
> Can you please provide a series of patches backported to the stable
> trees you feel these should go to, so I can apply them?
>

I can look into that sometime, but frankly, I don't feel strongly
either way about applying those patches to stable.
If anybody from ext4 developers can find the time to look into
that, I wouldn't object at all..

Thanks,
Amir.

Re: FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

[Amir Goldstein]

On Thu, Jul 5, 2018 at 8:07 PM, Amir Goldstein <amir73il@gmail.com> wrote:
> On Thu, Jul 5, 2018 at 7:29 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
>> On Thu, Jul 05, 2018 at 06:27:01PM +0200, Greg KH wrote:
>>> On Fri, Jun 22, 2018 at 12:25:43AM +0300, Amir Goldstein wrote:
>>> > On Fri, Jun 22, 2018 at 12:15 AM,  <gregkh@linuxfoundation.org> wrote:
>>> > >
>>> > > The patch below does not apply to the 4.17-stable tree.
>>> >
>>> > There is a [backport hint] at the end of the commit message.
>>> > Need to take the 2 prep commits.
>>> > Same for all stable branches.
>>> >
>>> > Cheers,
>>> > Amir.
>>> >
>>> > > If someone wants it applied there, or to any other stable or longterm
>>> > > tree, then please email the backport, including the original git commit
>>> > > id to <stable@vger.kernel.org>.
>>> > >
>>> > > thanks,
>>> > >
>>> > > greg k-h
>>> > >
>>> > > ------------------ original commit in Linus's tree ------------------
>>> > >
>>> > > From db6516a5e7ddb6dc72d167b920f2f272596ea22d Mon Sep 17 00:00:00 2001
>>> > > From: Amir Goldstein <amir73il@gmail.com>
>>> > > Date: Sun, 13 May 2018 22:54:44 -0400
>>> > > Subject: [PATCH] ext4: do not update s_last_mounted of a frozen fs
>>> > >
>>> > > If fs is frozen after mount and before the first file open, the
>>> > > update of s_last_mounted bypasses freeze protection and prints out
>>> > > a WARNING splat:
>>> > >
>>> > > $ mount /vdf
>>> > > $ fsfreeze -f /vdf
>>> > > $ cat /vdf/foo
>>> > >
>>> > > [   31.578555] WARNING: CPU: 1 PID: 1415 at
>>> > > fs/ext4/ext4_jbd2.c:53 ext4_journal_check_start+0x48/0x82
>>> > >
>>> > > [   31.614016] Call Trace:
>>> > > [   31.614997]  __ext4_journal_start_sb+0xe4/0x1a4
>>> > > [   31.616771]  ? ext4_file_open+0xb6/0x189
>>> > > [   31.618094]  ext4_file_open+0xb6/0x189
>>> > >
>>> > > If fs is frozen, skip s_last_mounted update.
>>> > >
>>> > > [backport hint: to apply to stable tree, need to apply also patches
>>> > >  vfs: add the sb_start_intwrite_trylock() helper
>>> > >  ext4: factor out helper ext4_sample_last_mounted()]
>>>
>>> For "hints", can you provide the git commit id in the future so I don't
>>> have to dig them out myself?
>>
>
> That would be chicken and egg.
> I wrote the hint when I posted the series so there was no upstream commit id
> at the time. Maybe I should have written "need to apply the 2 previous patches"
> as a hint... or could have tried to push back on review comments to split the
> patches.
>
>> And those backports don't apply properly :(
>>
>> Can you please provide a series of patches backported to the stable
>> trees you feel these should go to, so I can apply them?
>>
>

Greg,

The following upstream commit ids apply cleanly to current linux-4.17.y:
db6516a5e7dd ext4: do not update s_last_mounted of a frozen fs
833a950882d3 ext4: factor out helper ext4_sample_last_mounted()
0c8e3fe35db9 vfs: add the sb_start_intwrite_trylock() helper

I don't understand where in the process the problem was.
If you have any conclusions I would love to know so process
could be improved.

Thanks,
Amir.

Re: FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

[Jan Kara]

On Thu 05-07-18 20:07:32, Amir Goldstein wrote:
> On Thu, Jul 5, 2018 at 7:29 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
> > On Thu, Jul 05, 2018 at 06:27:01PM +0200, Greg KH wrote:
> >> On Fri, Jun 22, 2018 at 12:25:43AM +0300, Amir Goldstein wrote:
> >> > On Fri, Jun 22, 2018 at 12:15 AM,  <gregkh@linuxfoundation.org> wrote:
> >> > >
> >> > > The patch below does not apply to the 4.17-stable tree.
> >> >
> >> > There is a [backport hint] at the end of the commit message.
> >> > Need to take the 2 prep commits.
> >> > Same for all stable branches.
> >> >
> >> > Cheers,
> >> > Amir.
> >> >
> >> > > If someone wants it applied there, or to any other stable or longterm
> >> > > tree, then please email the backport, including the original git commit
> >> > > id to <stable@vger.kernel.org>.
> >> > >
> >> > > thanks,
> >> > >
> >> > > greg k-h
> >> > >
> >> > > ------------------ original commit in Linus's tree ------------------
> >> > >
> >> > > From db6516a5e7ddb6dc72d167b920f2f272596ea22d Mon Sep 17 00:00:00 2001
> >> > > From: Amir Goldstein <amir73il@gmail.com>
> >> > > Date: Sun, 13 May 2018 22:54:44 -0400
> >> > > Subject: [PATCH] ext4: do not update s_last_mounted of a frozen fs
> >> > >
> >> > > If fs is frozen after mount and before the first file open, the
> >> > > update of s_last_mounted bypasses freeze protection and prints out
> >> > > a WARNING splat:
> >> > >
> >> > > $ mount /vdf
> >> > > $ fsfreeze -f /vdf
> >> > > $ cat /vdf/foo
> >> > >
> >> > > [   31.578555] WARNING: CPU: 1 PID: 1415 at
> >> > > fs/ext4/ext4_jbd2.c:53 ext4_journal_check_start+0x48/0x82
> >> > >
> >> > > [   31.614016] Call Trace:
> >> > > [   31.614997]  __ext4_journal_start_sb+0xe4/0x1a4
> >> > > [   31.616771]  ? ext4_file_open+0xb6/0x189
> >> > > [   31.618094]  ext4_file_open+0xb6/0x189
> >> > >
> >> > > If fs is frozen, skip s_last_mounted update.
> >> > >
> >> > > [backport hint: to apply to stable tree, need to apply also patches
> >> > >  vfs: add the sb_start_intwrite_trylock() helper
> >> > >  ext4: factor out helper ext4_sample_last_mounted()]
> >>
> >> For "hints", can you provide the git commit id in the future so I don't
> >> have to dig them out myself?
> >
> 
> That would be chicken and egg.
> I wrote the hint when I posted the series so there was no upstream commit id
> at the time. Maybe I should have written "need to apply the 2 previous patches"
> as a hint... or could have tried to push back on review comments to split the
> patches.
> 
> > And those backports don't apply properly :(
> >
> > Can you please provide a series of patches backported to the stable
> > trees you feel these should go to, so I can apply them?
> >
> 
> I can look into that sometime, but frankly, I don't feel strongly
> either way about applying those patches to stable.
> If anybody from ext4 developers can find the time to look into
> that, I wouldn't object at all..

I will be probably eventually backporting these patches to SLE kernels so I
can forward them to stable then as well. But since this is really more of
an annoyance than a serious problem, it doesn't have high priority.

								Honza

-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

Re: FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

[Greg KH]

On Fri, Jul 06, 2018 at 11:45:04AM +0300, Amir Goldstein wrote:
> On Thu, Jul 5, 2018 at 8:07 PM, Amir Goldstein <amir73il@gmail.com> wrote:
> > On Thu, Jul 5, 2018 at 7:29 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
> >> On Thu, Jul 05, 2018 at 06:27:01PM +0200, Greg KH wrote:
> >>> On Fri, Jun 22, 2018 at 12:25:43AM +0300, Amir Goldstein wrote:
> >>> > On Fri, Jun 22, 2018 at 12:15 AM,  <gregkh@linuxfoundation.org> wrote:
> >>> > >
> >>> > > The patch below does not apply to the 4.17-stable tree.
> >>> >
> >>> > There is a [backport hint] at the end of the commit message.
> >>> > Need to take the 2 prep commits.
> >>> > Same for all stable branches.
> >>> >
> >>> > Cheers,
> >>> > Amir.
> >>> >
> >>> > > If someone wants it applied there, or to any other stable or longterm
> >>> > > tree, then please email the backport, including the original git commit
> >>> > > id to <stable@vger.kernel.org>.
> >>> > >
> >>> > > thanks,
> >>> > >
> >>> > > greg k-h
> >>> > >
> >>> > > ------------------ original commit in Linus's tree ------------------
> >>> > >
> >>> > > From db6516a5e7ddb6dc72d167b920f2f272596ea22d Mon Sep 17 00:00:00 2001
> >>> > > From: Amir Goldstein <amir73il@gmail.com>
> >>> > > Date: Sun, 13 May 2018 22:54:44 -0400
> >>> > > Subject: [PATCH] ext4: do not update s_last_mounted of a frozen fs
> >>> > >
> >>> > > If fs is frozen after mount and before the first file open, the
> >>> > > update of s_last_mounted bypasses freeze protection and prints out
> >>> > > a WARNING splat:
> >>> > >
> >>> > > $ mount /vdf
> >>> > > $ fsfreeze -f /vdf
> >>> > > $ cat /vdf/foo
> >>> > >
> >>> > > [   31.578555] WARNING: CPU: 1 PID: 1415 at
> >>> > > fs/ext4/ext4_jbd2.c:53 ext4_journal_check_start+0x48/0x82
> >>> > >
> >>> > > [   31.614016] Call Trace:
> >>> > > [   31.614997]  __ext4_journal_start_sb+0xe4/0x1a4
> >>> > > [   31.616771]  ? ext4_file_open+0xb6/0x189
> >>> > > [   31.618094]  ext4_file_open+0xb6/0x189
> >>> > >
> >>> > > If fs is frozen, skip s_last_mounted update.
> >>> > >
> >>> > > [backport hint: to apply to stable tree, need to apply also patches
> >>> > >  vfs: add the sb_start_intwrite_trylock() helper
> >>> > >  ext4: factor out helper ext4_sample_last_mounted()]
> >>>
> >>> For "hints", can you provide the git commit id in the future so I don't
> >>> have to dig them out myself?
> >>
> >
> > That would be chicken and egg.
> > I wrote the hint when I posted the series so there was no upstream commit id
> > at the time. Maybe I should have written "need to apply the 2 previous patches"
> > as a hint... or could have tried to push back on review comments to split the
> > patches.
> >
> >> And those backports don't apply properly :(
> >>
> >> Can you please provide a series of patches backported to the stable
> >> trees you feel these should go to, so I can apply them?
> >>
> >
> 
> Greg,
> 
> The following upstream commit ids apply cleanly to current linux-4.17.y:
> db6516a5e7dd ext4: do not update s_last_mounted of a frozen fs
> 833a950882d3 ext4: factor out helper ext4_sample_last_mounted()
> 0c8e3fe35db9 vfs: add the sb_start_intwrite_trylock() helper
> 
> I don't understand where in the process the problem was.
> If you have any conclusions I would love to know so process
> could be improved.

Yes, for 4.17 they did apply cleanly, but your patch says it should be
backported much further than that.  Is that request incorrect?

thanks,

greg k-h

Re: FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

[Amir Goldstein]

On Tue, Jul 10, 2018 at 3:24 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Fri, Jul 06, 2018 at 11:45:04AM +0300, Amir Goldstein wrote:
>> On Thu, Jul 5, 2018 at 8:07 PM, Amir Goldstein <amir73il@gmail.com> wrote:
>> > On Thu, Jul 5, 2018 at 7:29 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
>> >> On Thu, Jul 05, 2018 at 06:27:01PM +0200, Greg KH wrote:
>> >>> On Fri, Jun 22, 2018 at 12:25:43AM +0300, Amir Goldstein wrote:
>> >>> > On Fri, Jun 22, 2018 at 12:15 AM,  <gregkh@linuxfoundation.org> wrote:
>> >>> > >
>> >>> > > The patch below does not apply to the 4.17-stable tree.
>> >>> >
>> >>> > There is a [backport hint] at the end of the commit message.
>> >>> > Need to take the 2 prep commits.
>> >>> > Same for all stable branches.
>> >>> >
>> >>> > Cheers,
>> >>> > Amir.
>> >>> >
>> >>> > > If someone wants it applied there, or to any other stable or longterm
>> >>> > > tree, then please email the backport, including the original git commit
>> >>> > > id to <stable@vger.kernel.org>.
>> >>> > >
>> >>> > > thanks,
>> >>> > >
>> >>> > > greg k-h
>> >>> > >
>> >>> > > ------------------ original commit in Linus's tree ------------------
>> >>> > >
>> >>> > > From db6516a5e7ddb6dc72d167b920f2f272596ea22d Mon Sep 17 00:00:00 2001
>> >>> > > From: Amir Goldstein <amir73il@gmail.com>
>> >>> > > Date: Sun, 13 May 2018 22:54:44 -0400
>> >>> > > Subject: [PATCH] ext4: do not update s_last_mounted of a frozen fs
>> >>> > >
>> >>> > > If fs is frozen after mount and before the first file open, the
>> >>> > > update of s_last_mounted bypasses freeze protection and prints out
>> >>> > > a WARNING splat:
>> >>> > >
>> >>> > > $ mount /vdf
>> >>> > > $ fsfreeze -f /vdf
>> >>> > > $ cat /vdf/foo
>> >>> > >
>> >>> > > [   31.578555] WARNING: CPU: 1 PID: 1415 at
>> >>> > > fs/ext4/ext4_jbd2.c:53 ext4_journal_check_start+0x48/0x82
>> >>> > >
>> >>> > > [   31.614016] Call Trace:
>> >>> > > [   31.614997]  __ext4_journal_start_sb+0xe4/0x1a4
>> >>> > > [   31.616771]  ? ext4_file_open+0xb6/0x189
>> >>> > > [   31.618094]  ext4_file_open+0xb6/0x189
>> >>> > >
>> >>> > > If fs is frozen, skip s_last_mounted update.
>> >>> > >
>> >>> > > [backport hint: to apply to stable tree, need to apply also patches
>> >>> > >  vfs: add the sb_start_intwrite_trylock() helper
>> >>> > >  ext4: factor out helper ext4_sample_last_mounted()]
>> >>>
>> >>> For "hints", can you provide the git commit id in the future so I don't
>> >>> have to dig them out myself?
>> >>
>> >
>> > That would be chicken and egg.
>> > I wrote the hint when I posted the series so there was no upstream commit id
>> > at the time. Maybe I should have written "need to apply the 2 previous patches"
>> > as a hint... or could have tried to push back on review comments to split the
>> > patches.
>> >
>> >> And those backports don't apply properly :(
>> >>
>> >> Can you please provide a series of patches backported to the stable
>> >> trees you feel these should go to, so I can apply them?
>> >>
>> >
>>
>> Greg,
>>
>> The following upstream commit ids apply cleanly to current linux-4.17.y:
>> db6516a5e7dd ext4: do not update s_last_mounted of a frozen fs
>> 833a950882d3 ext4: factor out helper ext4_sample_last_mounted()
>> 0c8e3fe35db9 vfs: add the sb_start_intwrite_trylock() helper
>>
>> I don't understand where in the process the problem was.
>> If you have any conclusions I would love to know so process
>> could be improved.
>
> Yes, for 4.17 they did apply cleanly, but your patch says it should be
> backported much further than that.  Is that request incorrect?
>

Well, that's just miscommunication then.
I did not intend to request inclusion to any specific stable kernel.
The Fixes tag is informative - this is when bug was introduced.
The hint was meant to help whoever is picking up this commit
to stable kernel to know it has dependencies.
I agree with Jan that it is a rather corner issue that should be
treated as nice to have in stable kernels.
Anyway, seems that Jan has already "volunteered" to backport
the patches in some future time.

Thanks,
Amir.

Re: FAILED: patch "[PATCH] ext4: do not update s_last_mounted of a frozen fs" failed to apply to 4.17-stable tree

[Greg KH]

On Mon, Jul 09, 2018 at 03:52:58PM +0200, Jan Kara wrote:
> On Thu 05-07-18 20:07:32, Amir Goldstein wrote:
> > On Thu, Jul 5, 2018 at 7:29 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
> > > On Thu, Jul 05, 2018 at 06:27:01PM +0200, Greg KH wrote:
> > >> On Fri, Jun 22, 2018 at 12:25:43AM +0300, Amir Goldstein wrote:
> > >> > On Fri, Jun 22, 2018 at 12:15 AM,  <gregkh@linuxfoundation.org> wrote:
> > >> > >
> > >> > > The patch below does not apply to the 4.17-stable tree.
> > >> >
> > >> > There is a [backport hint] at the end of the commit message.
> > >> > Need to take the 2 prep commits.
> > >> > Same for all stable branches.
> > >> >
> > >> > Cheers,
> > >> > Amir.
> > >> >
> > >> > > If someone wants it applied there, or to any other stable or longterm
> > >> > > tree, then please email the backport, including the original git commit
> > >> > > id to <stable@vger.kernel.org>.
> > >> > >
> > >> > > thanks,
> > >> > >
> > >> > > greg k-h
> > >> > >
> > >> > > ------------------ original commit in Linus's tree ------------------
> > >> > >
> > >> > > From db6516a5e7ddb6dc72d167b920f2f272596ea22d Mon Sep 17 00:00:00 2001
> > >> > > From: Amir Goldstein <amir73il@gmail.com>
> > >> > > Date: Sun, 13 May 2018 22:54:44 -0400
> > >> > > Subject: [PATCH] ext4: do not update s_last_mounted of a frozen fs
> > >> > >
> > >> > > If fs is frozen after mount and before the first file open, the
> > >> > > update of s_last_mounted bypasses freeze protection and prints out
> > >> > > a WARNING splat:
> > >> > >
> > >> > > $ mount /vdf
> > >> > > $ fsfreeze -f /vdf
> > >> > > $ cat /vdf/foo
> > >> > >
> > >> > > [   31.578555] WARNING: CPU: 1 PID: 1415 at
> > >> > > fs/ext4/ext4_jbd2.c:53 ext4_journal_check_start+0x48/0x82
> > >> > >
> > >> > > [   31.614016] Call Trace:
> > >> > > [   31.614997]  __ext4_journal_start_sb+0xe4/0x1a4
> > >> > > [   31.616771]  ? ext4_file_open+0xb6/0x189
> > >> > > [   31.618094]  ext4_file_open+0xb6/0x189
> > >> > >
> > >> > > If fs is frozen, skip s_last_mounted update.
> > >> > >
> > >> > > [backport hint: to apply to stable tree, need to apply also patches
> > >> > >  vfs: add the sb_start_intwrite_trylock() helper
> > >> > >  ext4: factor out helper ext4_sample_last_mounted()]
> > >>
> > >> For "hints", can you provide the git commit id in the future so I don't
> > >> have to dig them out myself?
> > >
> > 
> > That would be chicken and egg.
> > I wrote the hint when I posted the series so there was no upstream commit id
> > at the time. Maybe I should have written "need to apply the 2 previous patches"
> > as a hint... or could have tried to push back on review comments to split the
> > patches.
> > 
> > > And those backports don't apply properly :(
> > >
> > > Can you please provide a series of patches backported to the stable
> > > trees you feel these should go to, so I can apply them?
> > >
> > 
> > I can look into that sometime, but frankly, I don't feel strongly
> > either way about applying those patches to stable.
> > If anybody from ext4 developers can find the time to look into
> > that, I wouldn't object at all..
> 
> I will be probably eventually backporting these patches to SLE kernels so I
> can forward them to stable then as well. But since this is really more of
> an annoyance than a serious problem, it doesn't have high priority.

Ok, given that this really isn't a big deal, I'll leave it as-is and
wait for backports to show up if you all happen to do them.

thanks,

greg k-h