Re: [PATCH v9 0/4] RISC-V: mm: Make SV48 the default address space

From: Charlie Jenkins
Date: Wed Aug 09 2023 - 18:45:39 EST


On Wed, Aug 09, 2023 at 08:42:58AM +0100, Conor Dooley wrote:
> On Tue, Aug 08, 2023 at 06:51:06PM -0700, Charlie Jenkins wrote:
> > Make sv48 the default address space for mmap as some applications
> > currently depend on this assumption. Users can now select a
> > desired address space using a non-zero hint address to mmap. Previously,
> > requesting the default address space from mmap by passing zero as the hint
> > address would result in using the largest address space possible. Some
> > applications depend on empty bits in the virtual address space, like Go and
> > Java, so this patch provides more flexibility for application developers.
>
> This still does not build:
> ../fs/binfmt_flat.c:900:30: error: call to undeclared function 'is_compat_task'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
>
> Reproduceable with allmodconfig.
>
There is some weird interaction with compat.h. Moving the definitions
in pgtable.h into the #ifndef __ASSEMBLY__ guarded section resolves
the compile error. I will send out another version with this change.

-Charlie