theoretical question about disks and os

[Matthew Dillon]

:Is it possible for a poorly written disk driver/filesystem to trash 
:blocks on a hard disk? By trashing I mean that subsequent access result 
:in an i/o error, aven accross reboot.

    No.  It's possible to purposefully blow up a disk by e.g. garbaging
    up the defect list and doing a format.  It isn't possible to do it
    accidently with normal reads and writes.

:I have such a disk where it happened a few years ago. Curiously, the 
:damaged blocks where the first blocks of partitions that where mounted. 
:The maker's test software says the drive's ok, as well as s.m.a.r.t., 
:although it needed a "reformat" with the same tool to get rid of the bad 
:blocks.

    It's unlikely that software had anything to do with the damage.  More
    likely the disk overheated or got jostled or had a failure just as 
    the filesystem happened to be doing a write to those sectors.

					-Matt
					Matthew Dillon 
					<dillon at xxxxxxxxxxxxx>

:I would think it must be some kind of hardware failure, but a recent 
:discussion about linux filesystems makes me wonder... linux was running 
:on that disk, after all, with reaiserfs. And it was 3 years ago.
:
:Raphael
: