scary fcache trouble - silent data corruption(?)

scary fcache trouble - silent data corruption(?)

[Paolo Ornati]

Hi, It's always me :)

This time I had a problem that scared me a bit...

Yesterday I've tested fcache for a while.

I have primed system boot + preferred applications startup, and then
I've used the system for a while.

Today I launch my mail-client (Sylpheed-Claws) and the Setup Wizard
dialog appears :-O!  (usually it appears when it isn't configured)

After a bit of reserch I've found that an XML config file
(.sylpheed-claws/folderlist.xml) was corrupted.

But it wasn't corrupted randomly, it was "replaced" with a peace of the
firefox cookies file :-X!


Now, Firefox and Sylpheed-Claws are 2 of the few application I've
primed... so my suspect is that there's some subtle BUG in fcache, or
maybe it's elsewhere since it is an experimental kernel after all...


Luckily	Sylpheed-Claws makes backup copy of every config file :)

The size of the corrupted file is almost identical to the backup one
(so it is probably equal to the size of the original one).


Even if there is really a BUG in fcache so that it can supply wrong
data I don't know how it got written to the real filesystem (since the
corruption persisted booting without fcache). Maybe Sylpheed-Claws have
read the file and then rewritten to it... I don't know.


Every time something like this happens I ask myself why I test
experimental things on my main PC...

I think this time I was lucky :)

-- 
	Paolo Ornati
	Linux 2.6.17-ga39727f2-dirty on x86_64