Disk change messages

Disk change messages

[Petr Konecny]

Hi,

I've been trying to use vold to automount CDs. The daemon tries to open
/dev/cdrom and if it succeeds it examines the media and mounts it under
/cdrom/volume_name.

The problem is that when there is no disk in the drive the following
message:
  VFS: Disk change detected on device ide1(22,0)
is written to system log during each open call.  Vold calls open every 5
seconds, so it's 17280 lines in log/day. I have been able to avoid these
messages by commenting out a line in drivers/ide/ide-cd.c (patch
included) and have not seen any problems yet.

I guess I have three questions:
 1. can this patch break things ? I suppose it could happen only
    if cdrom_saw_media_change was not called when the CD is changed.
 2. is it possible to avoid the message by modifying vold ? E.g. finding
    out that there is no media in the drive without calling open.
 3. is there a clean way to avoid these repeated messages ?

                                                Thanks, Petr

--- ide-cd.c    2001/02/22 22:30:02     1.1.1.11
+++ ide-cd.c    2001/02/27 19:51:58
@@ -601,7 +601,7 @@

                /* Check for tray open. */
                if (sense_key == NOT_READY) {
-                       cdrom_saw_media_change (drive);
+/*                     cdrom_saw_media_change (drive); */
                } else if (sense_key == UNIT_ATTENTION) {
                        /* Check for media change. */
                        cdrom_saw_media_change (drive);

Re: Disk change messages

[Pavel Machek]

Hi!

> I've been trying to use vold to automount CDs. The daemon tries to open
> /dev/cdrom and if it succeeds it examines the media and mounts it under
> /cdrom/volume_name.
> 
> The problem is that when there is no disk in the drive the following
> message:
>   VFS: Disk change detected on device ide1(22,0)
> is written to system log during each open call.  Vold calls open every 5
> seconds, so it's 17280 lines in log/day. I have been able to avoid these
> messages by commenting out a line in drivers/ide/ide-cd.c (patch
> included) and have not seen any problems yet.
> 
> I guess I have three questions:
>  1. can this patch break things ? I suppose it could happen only

No.

>  2. is it possible to avoid the message by modifying vold ? E.g. finding
>     out that there is no media in the drive without calling open.

Don't think so.

>  3. is there a clean way to avoid these repeated messages ?

Syslogdshould sumarize "last message repeated 123456 times"
.

>                                                 Thanks, Petr
> 
> --- ide-cd.c    2001/02/22 22:30:02     1.1.1.11
> +++ ide-cd.c    2001/02/27 19:51:58
> @@ -601,7 +601,7 @@
> 
>                 /* Check for tray open. */
>                 if (sense_key == NOT_READY) {
> -                       cdrom_saw_media_change (drive);
> +/*                     cdrom_saw_media_change (drive); */
>                 } else if (sense_key == UNIT_ATTENTION) {
>                         /* Check for media change. */
>                         cdrom_saw_media_change (drive);
> 
> -
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