Re: kern/42228: Kernel deadlock prevents further file system access

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Sun, Oct 25, 2009 at 02:05:03PM +0000, Matthias Scheler wrote:
>  >  > The function after "namei" differs from case to case. Examples are
>  >  > vn_open() or do_sys_stat().
>  >  
>  >  this looks a lot like the ffs VOP_RENAME race issue.
>  
>  Is there a patch available which I can try out?

A first try has been posted to tech-kern but unfortunably it's buggy
(and makes things worse, we now have "looking against myself" panics).

> And I don't understand
>  why that would happen frequently on one of my 24/7 NetBSD 5.0_STABLE
>  systems but not on the other, they both use FFS. Is it e.g. more likely
>  to happen on systems with multiple CPU cores?

Yes, multiple CPUs will make things worse, as does using WAPBL
(WAPBL is unusable for me on systems using rsync for example).

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--