Thread (7 messages) flat view 7 messages, 3 authors, 2009-03-23

Re: Fix for __div64_32 locks when using some 64 bit numbers

From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2009-03-17 23:03:11

On Tue, 2009-03-17 at 14:15 -0700, davidastro wrote:
I found a bug when using the function __div64_32 in assembly in a 32 bit ppc
architecture unit.

I tried the numbers 55834565048000000 for the dividend and 4294967079 for
the divisor. When passing these two numbers to the function  __div64_32, I
had a software lock. I searched for possible patches online and in different
forums but I could not find anything related to the assembly implementation
to this function (I would have to apologize if somebody already found a fix
:-) ).

Anyway, when analyzing the assembly code, I found out with gdb the problem.
I am not an expert in ppc architecture but I read the documentation and I am
pretty sure I solved the issue (I have been testing for couple of days using
random 64 to 32 number combinations with good results).

Who or Where should I post the fix to be reviewed.
Here is fine :-)

Ben.
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help