On Mon, Dec 30, 2019 at 6:39 PM Arnd Bergmann <arnd@xxxxxxxx> wrote: > > On Sun, Dec 22, 2019 at 2:25 PM <glider@xxxxxxxxxx> wrote: > > > > KMSAN instruments the code heavily, increasing register pressure and > > preventing functions from being inlined. As a result, the kernel > > requires more stack space to run. > > > > Rename KASAN_STACK_ORDER to EXTRA_STACK_ORDER and set EXTRA_STACK_ORDER > > to 2 for KMSAN builds, effectively making the stacks 4 times larger. > > > > Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx> > > What about CONFIG_FRAME_WARN? Do you need to change that as well to get > a warning-free build? If so, what is the minimum value that you need? Right now my config only yields a single warning about a frame of 2056 bytes. Actually, KMSAN tends to have even smaller frames than KASAN, so making the stacks so big might be too heavy-handed. I'll look into decreasing the stack sizes. -- Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Straße, 33 80636 München Geschäftsführer: Paul Manicle, Halimah DeLaine Prado Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg
