Bug#411813: linux-2.6/alpha: math-emu built as a module, should be built-in
Throughout the 2.6 kernel series, users of alpha systems of ev56-class and
below have been reporting problems with certain fp operations not working
correctly that did work when using 2.4 kernels.
The source of this behavior has recently been identified -- the math-emu
driver is configured as a module instead of being built-in, which it never
was before, and without this driver the kernel doesn't provide complete IEEE
The upstream description of this config option says:
This option is required for IEEE compliant floating point arithmetic
on the Alpha. The only time you would ever not say Y is to say M in
order to debug the code. Say Y unless you know what you are doing.
Not only that, it's not even *possible* to disable this driver when building
an SMP kernel. So the behavior is inconsistent between the SMP and UP alpha
kernel images; upstream discourages modularizing this driver at all except
for debugging; there is definitely a wide range of hardware where one would
never want to have this driver disabled as it will break fp math; and users
aren't going to know to look for this module.
Unless someone has a good reason why this should be built as a module, I
plan to update the configs for inclusion in the -11 upload.
Steve Langasek Give me a lever long enough and a Free OS
Debian Developer to set it on, and I can move the world.