Re: Differend udev names with different kernels

[Kay Sievers]

On Wed, Sep 24, 2008 at 13:01, Tino Keitel <tino.keitel@xxxxxx> wrote:
> what's the intention of /dev/disk/by-id/?
>
> My firewire hard disk seems to have different names with different
> kernels.
>
> With 2.6.26.3, it's name is
> /dev/disk/by-id/ieee1394-0030e001e0006585:00043c:0000.
>
> With someting after 2.6.27-rc7, merged with Arjan's fastboot branch,
> the disk has the same name.
>
> With 2.6.27-rc7, it is called
> /dev/disk/by-id/scsi-1WDC_WD10EACS-00D6B0_WD-WCAU41668315.

Seems, for some reason, the "ieee1394_id" attribute becomes readable
because of lucky timing, which wasn't the case before.

> One major config difference is that 2.6.26.3 has CONFIG_FIREWIRE and
> CONFIG_FIREWIRE_SBP2 set to "m", whereas the 2.6.27 kernels have set
> them to "y". But that doesn't explain the difference between both
> 2.6.27-rc kernels.

I guess, it's just a not-easy-to-reproduce timing issue with the sysfs
attribute.

> Shouldn't these names be somewhat constant? Otherwise they would be
> totally useless.

Yeah, sure they should not change like this.

We could just drop the ieee1394-* link creation entirely, if they
never worked as expected. Or we can provide it as an additional link
instead of making it skip the scsi-* link creation. Tino, care to try
if something like the attached works for your setup and creates at
least the scsi-links, and, if luckily timed, the ieee1394 links?

Stefan, ieee1394 hooks into scsi logic which, i guess, creates the
attribute _after_ event time, so udev will not see the attribute when
the device is announced. Any idea how to fix that?

Thanks,
Kay
diff --git a/rules/rules.d/60-persistent-storage.rules b/rules/rules.d/60-persistent-storage.rules
index 5218b2c..dec83cf 100644
--- a/rules/rules.d/60-persistent-storage.rules
+++ b/rules/rules.d/60-persistent-storage.rules
@@ -31,13 +31,16 @@ KERNEL=="hd*[!0-9]", IMPORT{program}="ata_id --export $tempnode"
 KERNEL=="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/ata-$env{ID_MODEL}_$env{ID_SERIAL}"
 KERNEL=="hd*[0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/ata-$env{ID_MODEL}_$env{ID_SERIAL}-part%n"
 
-KERNEL=="sd*[!0-9]|sr*", ATTRS{ieee1394_id}=="?*", ENV{ID_SERIAL}="$attr{ieee1394_id}", ENV{ID_BUS}="ieee1394"
 KERNEL=="sd*[!0-9]|sr*", ENV{ID_SERIAL}!="?*", SUBSYSTEMS=="usb", IMPORT{program}="usb_id --export %p"
 KERNEL=="sd*[!0-9]|sr*", ENV{ID_SERIAL}!="?*", IMPORT{program}="scsi_id --export --whitelisted -d $tempnode", ENV{ID_BUS}="scsi"
 KERNEL=="cciss?c[0-9]d[0-9]*", ENV{ID_SERIAL}!="?*", IMPORT{program}="scsi_id --export --whitelisted -d $tempnode", ENV{ID_BUS}="cciss"
 KERNEL=="sd*[!0-9]|sr*|cciss?c[0-9]d[0-9]*", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_BUS}-$env{ID_SERIAL}"
 KERNEL=="sd*[0-9]|cciss*p[0-9]*", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_BUS}-$env{ID_SERIAL}-part%n"
 
+# firewire
+KERNEL=="sd*[!0-9]|sr*", ATTRS{ieee1394_id}=="?*", SYMLINK+="disk/by-id/ieee1394-$attr{ieee1394_id}"
+KERNEL=="sd*[0-9]", ATTRS{ieee1394_id}=="?*", SYMLINK+="disk/by-id/ieee1394-$attr{ieee1394_id}-part%n"
+
 # libata compat (ata-* links, like old hd* devices did create)
 KERNEL=="sd*[!0-9]|sr*", ENV{ID_VENDOR}=="ATA", PROGRAM="ata_id $tempnode", RESULT=="?*", ENV{ID_ATA_COMPAT}="$result", SYMLINK+="disk/by-id/ata-$env{ID_ATA_COMPAT}"
 KERNEL=="sd*[0-9]", ENV{ID_ATA_COMPAT}=="?*", SYMLINK+="disk/by-id/ata-$env{ID_ATA_COMPAT}-part%n"