"removable" flag

[Andreas Schuldei]

* Andreas Schuldei (andreasٌ+linux-fai at schuldei.org) [080228 21:29]:
> hi!
> 
> I have a raid array that gets detected as "removable". that looks
> like this in dmesg:
> 
> Adaptec aacraid driver (1.1-5[2409]-mh2)
> AAC0: kernel 5.2-0[15583]
> AAC0: monitor 5.2-0[15583]
> AAC0: bios 5.2-0[15583]
> AAC0: serial aa0473
> AAC0: Non-DASD support enabled.
> AAC0: 64bit support enabled.
> AAC0: 64 Bit DAC enabled
> scsi0 : aacraid
>   Vendor: Sun       Model: main              Rev: V1.0
>   Type:   Direct-Access                      ANSI SCSI revision: 02
>   Vendor: SEAGATE   Model: ST914602SSUN146G  Rev: 0603
>   Type:   Direct-Access                      ANSI SCSI revision: 05
>   Vendor: SEAGATE   Model: ST914602SSUN146G  Rev: 0603
>   Type:   Direct-Access                      ANSI SCSI revision: 05
>   Vendor: SEAGATE   Model: ST914602SSUN146G  Rev: 0603
>   Type:   Direct-Access                      ANSI SCSI revision: 05
>   Vendor: SEAGATE   Model: ST914602SSUN146G  Rev: 0603
>   Type:   Direct-Access                      ANSI SCSI revision: 05
>   Vendor: ADAPTEC   Model: Virtual SGPIO  0  Rev: 0001
>   Type:   Enclosure                          ANSI SCSI revision: 05
> usb 1-1: configuration #1 chosen from 1 choice
>   Vendor: ADAPTEC   Model: Virtual SGPIO  1  Rev: 0001
>   Type:   Enclosure                          ANSI SCSI revision: 05
> SCSI device sda: 573030400 512-byte hdwr sectors (293392 MB)
> sda: assuming Write Enabled
> sda: assuming drive cache: write through
> SCSI device sda: 573030400 512-byte hdwr sectors (293392 MB)
> sda: assuming Write Enabled
> sda: assuming drive cache: write through
>  sda: sda1 sda2
> sd 0:0:0:0: Attached scsi removable disk sda
> 
> 
> 
> (last line there it says "removable")
> 
> and true enough, in /sys/block/sda/removable there is a "1".
> 
> FAI uses /usr/lib/fai/disk-info to get its list of disks that it
> could partition, and checks if /sys/block/sda/removable to remove
> removable devices from the list. I checked if the aacraid module
> had an option so that i could get a non-removable sda device, but
> it does not.
> 
> does someone have a tip how to solve this cleanly? just
> commenting out the check against /sys/block/sda/removable is
> possible but breaks in other situations of course.
> 

this is directly related to bug
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=404927

aparently the removable flag is used against partition table
caching. the udev fix for the bug was applied. it moves the disk
into the "disk" group (out of the "floppy" group). this could be
a way to check if a device should be removed from the list of
devices, btw, instead of the "removable" flag.

as it looks my best bet is to use a bigger kernel where this is
fixed.

/andreas