I know there's some magic somewhere in the Makefiles that automatically
builds both "normal" and XEN variants of the modules for amd64 (and, for
i386, there's a PAE variant, too)! But I can't seem to find the magic!
Anyway, it seems to me that, when building the XEN (or PAE) variants of
each module, they should be built with -DXEN (or -DPAE) options. There is
at least one source file, compiled into the compat module, which has some
code conditional on XEN. (For those who care, it is the compat_60 x86
code for updating AMD cpu_ucode.)
Based on log files, we're currently not defining XEN or PAE for the
modules builds. As a result the XEN variant of the compat module does not
contain the required code, preventing use of the 6.0 cpuctl command.
So,
1. Would it be reasonable to define the XEN and PAE macros when building
the module variants?
Still need an answer to this question...
2. What would it take to make it happen?
Add
CPPFLAGS+= -DXEN (or PAE)
to the appropriate *.mk files? (See #3 below) These files already have
XEN= 1
and PAE= 1
3. Where's the magic? :)
OK, found the magic. It's in
src/sys/modules/arch/x86/amd64-xen/bsd.amd64-xen.mk
src/sys/modules/arch/x86/i386-xen/bsd.i386-xen.mk
and src/sys/modules/arch/x86/i386pae-xen/bsd.i386pae-xen.mk
If the answer to Question #1 is "Yes, it's reasonable" then I can take care
of making the changes.
Follow-on question: the changes identified above have the desired effect,
and code conditioned on XEN is now being built. Unfortunately, that has
exposed the next problem!
The XEN-specific code has a
#include "xen/intrptrs.h"
which for kernel builds would be found due to a sym-link in the kernel's
object directory:
xen -> /build/netbsd-compat/src/sys/arch/xen/include
This symlink doesn't exist in the module's object directory, so the #include
fails.
It would appear that I might need to add some more magic to create the xen
(and/or pae) symlink for the modules. It looks like this is handled in
share/mk/bsd.klinks.mk but it's not exactly clear what I should add. And I
can't seem to find where the kernel Makefiles make this happen, so no
examples from which to borrow. I can't tell if I should (a) set XEN_BUILD to
something (to what?), (2) override an existing value of KLINK_MACHINE, or (3)
just update KLINK_FILES? (And what is xen-ma used for, anyway?)
Again, any clue/help would be greatly appreciated.
(As you all can probably tell from this thread, I'm far from an expert when
it comes to our build infrastructure...)
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| Paul Goyette | PGP Key fingerprint: | E-mail addresses: |
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