On Fri, 19 Dec 2014, Markos Chandras wrote:

quoted

quoted

The use of "add" instruction for immediate operations is wrong and
relies to gas being smart enough to notice that and replace it with
either addi or addui. However, MIPS R6 removed the addi instruction
so, fix this problem properly by using the correct instruction
directly.

 Not true, depending on the arguments the ADD assembly macro expands to 
either of the ADD and the ADDI hardware instructions; where an immediate 
outside the 16-bit signed range is used it also expands to a longer 
sequence involving LUI and the actual operation is ADD.  It never expands 
to ADDIU (which I gather you meant).

quoted

This is another case of the use of "add" being a real bug.  We should
never have faulting instructions like this in the kernel.

Can you send all patches in this set that fix this bug as a separate
patch?  Since they are obviously correct, and really should be used by
all non-R6 processors, we can get them in sooner that the entire R6 thing.

Thanks,
David Daney

sure i will move these patches away from R6 and post them separately.

 I think using the ADDU macro is preferred here as it allows arbitrary 
32-bit values for `off', just like with memory references in MIPS assembly 
instructions.

  Maciej