On Fri, May 21, 2021 at 11:03:11AM +0200, lukas@herbolt.com wrote:

quoted

Are you going to wire up fs uuid logging for the other filesystems that
support them?

Well, I wasn't planning to but I can take a look on other FS as well
Ext4 and Btrfs for start.

quoted

What happens w.r.t. uuid disambiguation if someone uses a nouuid mount
to mount a filesystem with the same uuid as an already-mounted xfs?

I a not sure I understand the "nouuid mount". I don't think there can
be XFS with empty uuid value in SB. And printing the message is independent
on the mount method (mount UUID="" ...; mount /dev/sdX ...;).

I meant specifically:

mount /dev/mapper/fubar /mnt
<snapshot fubar to fubar.bak>

Oh no, I deleted something in fubar, let's retrieve it from fubar.bak!

mount /dev/mapper/fubar.bak /opt	# fails because same uuid as fubar
mount /dev/mapper/fubar.bak /opt -o nouuid

--D

On 20.05.2021 17:23, Darrick J. Wong wrote:

quoted

On Wed, May 19, 2021 at 05:22:48PM +0200, Lukas Herbolt wrote:

quoted

As of now only device names are printed out over __xfs_printk().
The device names are not persistent across reboots which in case
of searching for origin of corruption brings another task to properly
identify the devices. This patch add XFS UUID upon every mount/umount
event which will make the identification much easier.

A few questions....

Are you going to wire up fs uuid logging for the other filesystems that
support them?

What happens w.r.t. uuid disambiguation if someone uses a nouuid mount
to mount a filesystem with the same uuid as an already-mounted xfs?

The changes themselves look ok, but I'm wondering what the use case is
here.

--D

quoted

Signed-off-by: Lukas Herbolt <redacted>
---
V2: Drop void casts and fix long lines

 fs/xfs/xfs_log.c   | 10 ++++++----
 fs/xfs/xfs_super.c |  2 +-
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 06041834daa31..8f4f671fd80d5 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c

@@ -570,12 +570,14 @@ xfs_log_mount(
 	int		min_logfsbs;

 	if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) {
-		xfs_notice(mp, "Mounting V%d Filesystem",
-			   XFS_SB_VERSION_NUM(&mp->m_sb));
+		xfs_notice(mp, "Mounting V%d Filesystem %pU",
+			   XFS_SB_VERSION_NUM(&mp->m_sb),
+			   &mp->m_sb.sb_uuid);
 	} else {
 		xfs_notice(mp,
-"Mounting V%d filesystem in no-recovery mode. Filesystem will be

inconsistent.",
-			   XFS_SB_VERSION_NUM(&mp->m_sb));
+"Mounting V%d filesystem %pU in no-recovery mode. Filesystem will
be inconsistent.",
+			   XFS_SB_VERSION_NUM(&mp->m_sb),
+			   &mp->m_sb.sb_uuid);
 		ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
 	}

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index e5e0713bebcd8..a4b8a5ad8039f 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c

@@ -1043,7 +1043,7 @@ xfs_fs_put_super(
 	if (!sb->s_fs_info)
 		return;

-	xfs_notice(mp, "Unmounting Filesystem");
+	xfs_notice(mp, "Unmounting Filesystem %pU", &mp->m_sb.sb_uuid);
 	xfs_filestream_unmount(mp);
 	xfs_unmountfs(mp);

--

2.31.1