[PATCH v1] Add Loongson2F specific NOP instruction

[Maciej W. Rozycki]

On Sun, 15 Nov 2009, Wu Zhangjin wrote:

> > Wu Zhangjin <wuzhangjin@gmail.com> writes:
> > > I'm sorry, "addu v0,zero,v0" may make kernel hang at "ld      a0,0(v0)",
> > > I need to change it be something else.
> 
> Herein, I use "addu at,at,zero"(move at,at) as a work around, have
> tested it with gcc 4.5 on the linux kernel 2.6.32-rc7.

 Hmm, given the above are you sure that "ld a0,0(at)" won't trigger the 
same problem?  Or is it the source and target register swap that is the 
guarantee for the erratum to be avoided and the change to "at" with this 
update is cosmetic?

 Note that you don't know what kind of code people will try to use with 
this workaround and while the Linux kernel may be important it is not 
representative.  It would be better if the exact nature of the erratum was 
known and the triggering conditions avoided.

  Maciej