[Lustre-discuss] SCSI driver problem on 2.6.22.19 + lustre 1.8.1?

[Nirmal Seenu]

I uncompressed linux-2.6.22.19.tar,gz into two different directories and 
  applied 1.8.0.1 patches to one directory and then 1.8.1 into the other.

I compared each file that was listed as files patched by the quilt 
command in both the kernel source tree directory and found that the 
following line to be different in: fs/jbd/transaction.c

In lustre 1.8.0.1 it used to be:

journal->j_commit_timer.expires = round_jiffies(transaction->t_expires);

and it is the following in Lustre 1.8.1:

   journal->j_commit_timer.expires = transaction->t_expires;

I guess this patch was applied based on the these bug and it seems to 
fix the problem with the Redhat and SLES kernels and break vanilla kernels:

http://kerneltrap.org/Linux/High_Idle_Load_Average

https://bugzilla.lustre.org/show_bug.cgi?id=19321

The only other differnece is from the 8kstack-2.6.12.patch which used to 
modify the following line in include/asm-i386/thread_info.h

from
  #define THREAD_SIZE            (4096)
to
  #define THREAD_SIZE            (8192)

It seems like, it would be safe for me to rollback the changes to 
fs/jbd/transaction.c and continue using 2.6.22.19 kernel.

Thanks
Nirmal