Re: CVS commit: src/sys/arch

[Maxime Villard <max%m00nbsd.net@localhost>]

Le 12/05/2016 15:31, Joerg Sonnenberger a écrit :
> On Thu, May 12, 2016 at 06:45:17AM +0000, Maxime Villard wrote:
> > Module Name:	src
> > Committed By:	maxv
> > Date:		Thu May 12 06:45:16 UTC 2016
> >
> > Modified Files:
> > 	src/sys/arch/amd64/amd64: locore.S machdep.c
> > 	src/sys/arch/amd64/conf: kern.ldscript
> > 	src/sys/arch/i386/conf: kern.ldscript
> > 	src/sys/arch/i386/i386: locore.S
> > 	src/sys/arch/x86/x86: db_memrw.c pmap.c
> >
> > Log Message:
> > Split the {text+rodata} chunk in two separate chunks on x86. The
> > rodata segment now loses the large page optimization, gets mapped inside
> > the data segment, and therefore becomes RWX. It may break the build on
> > Xen.
>
> This was not discussed anywhere. I'm not even convinced it is a good
> idea. So why has this been just committed?

It was a temporary - but necessary - step towards mapping the segments
independently and applying proper permissions on them.

I then resplit the rodata+data+bss+PRELOADED_MODULES+BOOTSTRAP_TABLES chunk
on amd64 into three rodata, data+bss and PRELOADED_MODULES+BOOTSTRAP_TABLES
chunks, each one getting respectively R, RW and RWX. The last chunk still
needs to be split once again. I'll then have to apply the same in i386.

It's all explained in the commit messages that came afterwards.