[OpenAFS-devel] Re: 1.2.10 linux kernel hang during AFS backups

[Joe Buehler]

Some further information:

When the deadlock occurs, the client is prefetching
into the client cache.  There is heavy VM pressure.
When the writeback to disk is about to happen, a page
is needed and this causes kswapd to wake up to try to
free some pages.  Unfortunately, it chooses a page
in the cache file being prefetched, causing a deadlock.

It looks like a lot of locking changes were made in 1.3
in afs_GetDCache for other reasons -- I guess something
may have to change in there to fix this problem.
-- 
Joe Buehler