On Thu, Mar 06, 2025 at 04:59:53PM +0800, David Gow wrote: > On Wed, 5 Mar 2025 at 00:21, Kees Cook <[email protected]> wrote: > > > > The UM builds distinguish i386 from x86_64 via SUBARCH, but we don't > > support building i386 directly with Clang. To make SUBARCH work for > > i386 UM, we need to explicitly test for it. > > > > This lets me run i386 KUnit tests with Clang: > > > > $ ./tools/testing/kunit/kunit.py run \ > > --make_options LLVM=1 \ > > --make_options SUBARCH=i386 > > ... > > > > Fixes: c7500c1b53bf ("um: Allow builds with Clang") > > Signed-off-by: Kees Cook <[email protected]> > > --- > > Thanks for this -- I'd been using `--kconfig_add CONFIG_64BIT=n` as a > way to build i386 UML kernels, which seems to work even without this > patch -- but this is definitely an improvement.
Thanks! Yeah, I figured there must have been a way to get at it. I wanted to make it work the "normal" way. > It may be worth noting that CONFIG_FORTIFY_SOURCE is incompatible with > clang + i386, which seems to affect UML as well. (That might actually > not be required, as I think UML doesn't use any of the strange > -mregparm calling convention stuff which appears to be what breaks > FORTIFY_SOURCE here.) Also fixed! :) https://lore.kernel.org/lkml/[email protected]/ > Tested-by: David Gow <[email protected]> Thanks for testing; I've updated the trailers in my tree. -Kees -- Kees Cook
