I noticed that on at least the first system I looked at (Ubuntu 18.04) it defaults to KERN_WARNING (ie 4) so wouldn't have shown a KERN_INFO which is level 6 (as the mount example from ext4) by default or the xfs_notice (which is level 5) https://elinux.org/Debugging_by_printing On Tue, Oct 2, 2018 at 2:28 PM Rodrigo Freire <rfreire@xxxxxxxxxx> wrote: > > Hi Steve, > > ----- Original Message ----- > > From: "Steve French" <smfrench@xxxxxxxxx> > > To: rfreire@xxxxxxxxxx > > Cc: "LKML" <linux-kernel@xxxxxxxxxxxxxxx>, "Steve French" > > <sfrench@xxxxxxxxx>, "CIFS" <linux-cifs@xxxxxxxxxxxxxxx>, "Pavel Shilovsky" > > <piastryyy@xxxxxxxxx> > > Sent: Tuesday, October 2, 2018 4:17:02 PM > > Subject: Re: [PATCH v2] CIFS: Print message when attempting a mount > > > > Are you sure that these aren't logged by the automounter (for ext4, > > xfs etc.). When I looked in my dmesg logs I didn't find matching log > > entries in the file systems themselves. Do you have an example? > > I'm positive about it. Check it out: > > [rfreire@rf ~]$ cd git/upstream/fs/ext4/ > [rfreire@rf ext4]$ > [rfreire@rf ext4]$ > [rfreire@rf ext4]$ grep -r "mounted filesystem with" > super.c: ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. " > > > [rfreire@rf ext4]$ dmesg | grep mount > [ 21.550897] EXT4-fs (dm-1): mounted filesystem with ordered data mode. Opts: (null) > [ 22.216213] EXT4-fs (dm-1): re-mounted. Opts: discard > [ 22.598267] EXT4-fs (sda1): mounted filesystem with ordered data mode. Opts: (null) > [ 22.605225] EXT4-fs (sdc): mounted filesystem without journal. Opts: discard > [ 24.029161] EXT4-fs (dm-2): mounted filesystem with ordered data mode. Opts: (null) > [ 24.047777] EXT4-fs (dm-4): mounted filesystem without journal. Opts: (null) > > XFS sample dmesg (from https://www.reddit.com/r/archlinux/comments/40b9r9/xfs_partition_is_mounted_during_boot_and_then/): > > [ 2.764491] XFS (sdb1): Mounting V5 Filesystem > [ 3.200886] XFS (sdb1): Ending clean mount > [ 5.384218] XFS (sdb1): Unmounting Filesystem > > Relevant code: > > [rfreire@rf ~]$ cd ../xfs > > [rfreire@rf xfs]$ grep "Mounting V" *.c > xfs_log.c: xfs_notice(mp, "Mounting V%d Filesystem", > > > > On the idea of adding cifsFYI logging here - I slightly prefer using > > ftrace (trace-cmd, ie dynamic tracing) so there is less overhead and > > easier to turn on/off following the example of xfs, f2fs, nfs, nfsd > > etc. > > Remember that cifsFYI already exists; I just moved it inside a if clause > to print it only when running under debug. (they way it is originally). > > > On Tue, Oct 2, 2018 at 6:57 AM Rodrigo Freire <rfreire@xxxxxxxxxx> wrote: > > > > > > Currently, no messages are printed when mounting a CIFS filesystem and > > > no debug configuration is enabled. > > > > > > However, a CIFS mount information is valuable when troubleshooting > > > and/or forensic analyzing a system and finding out if was a CIFS > > > endpoint mount attempted. > > > > > > Other filesystems such as XFS, EXT* does issue a printk() when mounting > > > their filesystems. > > > > -- > > Thanks, > > Thank You! o/ -- Thanks, Steve
